In the following examples, we have used the prepositions "in" before "suburbs" and "on" before " outskirts". Is there any explation for this usage?   I live in the suburbs of London. I live on the outskirts of London.

Which of the following sentences is correct, and why?     I bought a house in the outskirts of the city.   I bought a house on the outskirts of the city.


Is there a word that can be used to refer to all the items in a list or sequence which is not the first item? For example, take this list:  (oranges, apples, raspberries, pears)  How can I refer to (apples, raspberries, and pears)?

Is there a word to describe something that is not the first element in a sequence, but can be in any other position? A synonym of "not first", in fact.     This element is __ in this sequence.


I'm trying to automatically mount a NAS drive on start. The command I'm using to manually mount it is:  sudo mount -t nfs 192.168.1.88:/NAS /media/nas   This works fine. This is what I'm putting in my fstab file which isn't working:  //192.168.1.57/nas /media/nas nas _netdev,auto 0 0   No doubt a basic error but my googling has failed me. Thanks very much.

I am trying to auto-mount my NFS drives, but it doesn't work too well sadly.  What does work is mounting from CLI:  me@client:/$ sudo mount 192.168.178.4:/mountdir /mnt/mountdir me@client:/$ mount -t nfs 192.168.178.4:/mountdir on /mnt/mountdir type nfs (rw,addr=192.168.178.4)   when I try to add mountdir in the fstab, I cannot mount it due to "protocol not supported" (which seems strange as I can mount it)  $ sudo mount films_d3 mount.nfs: Protocol not supported   So there might be something wrong with my fstab entry. This is my current entry:  192.168.178.4:/mountdir /mnt/mountdir  nfs auto,_netdev,noatime,nolock,bg,nfsvers=4,intr,tcp,actimeo=1800 0 0   During startup I also get this error twice: I was trying to fix the mount-from-fstab first, then worry about that, but nevertheless this might be a different problem:  init: idmapd-mounting (/mnt/kazemat/films_d3) main process (445) killed by TERM signal   This seems to be before the eth0 is initialised, while I thought the "_netdev" option would make the entry wait for the network to be up?  can anywone see the mistake in my fstab entry?


Is there a function working like UNION on different SELECT statements that does not remove duplicates? Or any other way of creating one big column out of few smaller ones without loosing any data? Example: INPUT col_1,    col_2,     text1    text3         text2    text2         text3    text1       OUTPUT col_3 text1 text2 text3 text3 text2 text1

What is the difference between UNION and UNION ALL?


I am really interested in learning about black holes, and tbh I know absolutely nothing about them. But I am really eager to learn about them. So I'm searching for books that can teach me in easy comprehensible english.

I’m studying a PhD in Theoretical Physics (quantum field theory, to be specific), but I would like to learn more about black holes (and related areas. Does anyone have any suggestions for textbooks/available notes on these subjects for people without much background in them? Obviously I’m very comfortable with mathematics and physics in general so I’m not looking for “pop science” material.


//Testing Function function testEqual(test, expect, got){   console.log(`Testing ${test}`);   if (expect === got){     console.log(`${test} has passed`);     return true;   } else {     console.log(`${test} has failed, expected ${expect} but got ${got}`);     return false;   } }  //Run the tests let passed = 0; let tests = {   "temperatureCtoF":[75, temperatureCtoF(24)],   "temperatureInF Part 1":["88F", temperatureInF(88, 'F')],   "temperatureInF Part 2":["75F", temperatureInF(24, 'C')],   "makePersonObject": [{"id": 5, "name": 'Leia', "email": 'leia@leia.com'}, makePersonObject(5, "red", "leia@leia.com")], } console.log(tests["makePersonObject"]);  console.log(testEqual("makePersonObject", tests["makePersonObject"][0],tests["makePersonObject"][1]));   On the above code, I created a testEquals function and a bunch of tests, for the final test, I get the output "Testing makePersonObject index.js:212 makePersonObject has failed, expected [object Object] but got [object Object]" and I can't seem to figure out how to compare them correctly, I tried using === and .value in my test function but that didn't work.

A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java?  Stack Overflow question  is similar to this question, but requires a more academic answer. The scenario above demonstrates why it would be necessary to have one, and I'm wondering if there is any equivalent solution.


Say I have a Zombie token, , and  on the battlefield. Can I sacrifice the Zombie token to activate both the Altar's and Seer's abilities?  Similarly, if I have one card in hand, and  and  on the battlefield can I discard the one card to both of their abilities?  If I have a  with 3 charge counters can I activate both of its abilities by tapping it to add a counter, and tapping it to remove 3 counters and destroy a permanent without untapping it in between?

I'm starting on mono blue mill deck and I saw . I'm not sure about its ability.     {tap}: put a charge counter on Grindclock      {tap}: target player puts the top X cards of his or her library into his or her graveyard, where X is the number of charge counters on Grindclock.   If I just cast  and use its first ability, will the second ability take effect, or do I just put a charge counter on it? If there's already one charge counter on it and I use the first ability again, it will have two charge counters on it? Then the second ability will take effect with two cards being sent to graveyard?  If I use spells or ability to untap it after being used can I use its ability again on the same turn?


I am writing a PhD thesis in robotics and I was wondering if it sounds good to start a phrase with: 'According to Wikipedia ...'  Do you think I can do that or not?

For example, suppose you're writing an article about triangles, and you want to include a short proof of Pythagoras' theorem, but you can't quite remember how to derive it, so you pop over to:  and check the proof there. It works mathematically, makes sense and is as far as you can tell, correct, so you include it. Now the proof on Wikipedia doesn't have a citation because probably someone has been taught it and copied it over to Wikipedia, but it's still correct. The only thing you could cite for the proof would be Wikipedia, would a citation be ok or should it just be copied down without a citation?  Edit: Ok, there have been many responses. Most with a firm "no", but some giving the reason: "Just get the proof from a book" since it's so common, but suppose then it wasn't a common proof of something. Maybe it's not very well known or something but suppose there is a small Wikipedia page with the correct mathematical proof. How much effort are people going to go to to find a proof in a book when there's a (correct (which we know, becuase it's maths and we can check it)) proof on Wikipedia? Why is it so bad to say: "I found this proof on Wikipedia, and the maths checks out so it doesn't matter who wrote it, it is correct, but that's where I found it." Or if you do find it somewhere else why not say: "Proof taken from Wikipedia and verified by the proof shown in "Triangles and their properties, Nature, 2014, p113 etc..."


Let $f, g : X \to Y$ be continuous functions. Assume that $Y$ is Hausdorff and that there exists a dense subset $D$ of $X$ such that $f(x) = g(x)$ for all $x \in D$. Prove that $f(x) = g(x)$ for all $x \in X$.  Here is what I have so far,  Proof: Let $f : X \to Y$ and $g : X \to Y$ be continuous and suppose that $f(x)=g(x)$ for some dense $D\subset  X$. Let $x  \in X$, since $D$ is a dense subset of $X$, $x  \in \mathrm{Cl}(D)$. I'm unsure how to proceed from here.

Problem:      Suppose $f$ and $g$ are two continuous functions such that $f: X \to Y  $ and $g : X \to Y $. $Y$ is a a Hausdorff space. Suppose $f(x) = g(x)  $ for all $x \in A \subseteq X $ where $A$ is dense in $X$, then $f(x)  = g(x) $ for all $x \in  X $.   Attempt at a solution:  Put $h(x) = f - g $. Therefore, $h: X \to Y $ is continuous and $Y$ is Hausdorff by hypothesis. Also we know $h(x) = 0 $ for all $x \in A $ such that $A$ is dense in $X$. I want to show that $h(x)$ vanishes everywhere in $X$. We can show $h(x) = 0 $ for all $x \in X \setminus A $. Suppose $h(x) > 0 $ on $X \setminus A$. Pick points $y_1,y_2 \in Y $. Since $Y$ is Hausdorff, can find open set $O_1, O_2 \subseteq Y $ which are disjoint such that $y_1 \in O_1$ and $y_2 \in O_2$. By continuity, $f^{-1}(O_1), f^{-1}(O_2)$ are open in $X$.   I know that if I can show that one of the $f^{-1}(O_i)$ lies in $X \setminus A $, then we would have a contradiction since we have non-empty open set in $X \setminus A$ and this implies $A$ cannot be dense in $X$. But this is the part I am stuck. Any help would greatly be appreciated.  Also, Would be be possible to prove this without using the Hausdorff condition on $Y$?


When an object, say a ball,  is attracted by the black hole it gets acceleration due to gravity. Suppose light is moving towards the black hole vertical to it... then does it gain acceleration due to gravity?  If yes then won't be the speed of light increase and get violated?

Gravity causes anything with energy to accelerate toward the source. Black holes, for example, have such strong gravity that they pull in light and don't let any escape. But can acceleration still apply to light? The speed of light is constant, of course, but why are photons affected by gravity yet aren't accelerated by it?  Edit: My main question is why photons aren't affected in the same way as most other particles. I'm perfectly aware that it cannot surpass lightspeed, but I want to know what makes it unaffected by acceleration while other particles are affected.


Prove or give a counterexample: if $U_1$, $U_2$, $W$ are subspaces of $V$ such that $V$ = $U_1\oplus W$   and  $V = U_2 \oplus W$, then $U_1 = U_2$.  I'm a beginner in linear algebra and I'm frustrated at these types of questions, could you please offer an example solution?  Thanks in advance.

Is it true that if $ U \oplus W_1 = U \oplus W_2 $, then $ W_1 = W_2 $? I think that if $ U \oplus W_1 = U \oplus W_2 $, then u+w1=u+w2, so W1=W2. But did I make any mistakes?


I'm using the OpenFileDialog to open an Excel workbook, pass data from that workbook to another workbook, and then close the workbook I opened via OpenFileDialog. My problem is passing the data...how do I obtain just the name of the file I've opened via OpenFileDialog? I can't have the path, I just need the name of the file with it's extension. Here's part of my code   Dim filedialog As OpenFileDialog = New OpenFileDialog() Dim strFileName As String                 filedialog.Title = "Open File Dialog"                 filedialog.InitialDirectory = "W:\TOM\ERIC\NET Dev"                 filedialog.RestoreDirectory = True                 If filedialog.ShowDialog() = DialogResult.OK Then                     strFileName = filedialog.FileName                     System.Diagnostics.Process.Start(strFileName)                     StatVar.xlApp.Workbooks(StatVar.workbookName).Sheets("Input Form     Info").Range("B4:B204").Value = StatVar.xlApp.Workbooks(strFileName).Sheets("DJA Corp     Use").Range("C2:C202").Value                     StatVar.xlApp.Workbooks(strFileName).Close(False)                 End If             Else                 Exit Sub             End If   I can't pass my data from workbook to workbook because the strFileName variable contains the file path. I've been trying to work with this function to return the file name but I'm not experienced enough apparently. Any help is appreciated.      Public Function FileNameWithoutPath(ByVal FullPath As String) As String      Return System.IO.Path.GetFileName(FullPath).ToString      End Function

I am using the following method to browse for a file:      OpenFileDialog.ShowDialog()     PictureNameTextEdit.Text = OpenFileDialog.FileName   Is there a way get ONLY the file name?  The FileName method returns the entire path and file name.  i.e. I want Foo.txt instead of C:\SomeDirectory\Foo.txt


Say I have a class A:  class A:     list_attribute = ['foo', 'bar']     dict_attribute = {'foo': 'bar'}   A is extended by B, and in B I want to add elements to list_attribute in the declaration of the class, it is pretty easy   class B(A):     list_attribute = A.list_attribute + ['foobar', 'barfoo']   My question is, how can I add elements to the dict_attribute the same way I did for the list_attribute (in the attribute definition, and not in the __init__), since dicts don't support the + operator ?  Thanks in advance and have a great day!

I have two Python dictionaries, and I want to write a single expression that returns these two dictionaries, merged (i.e. taking the union).  The update() method would be what I need, if it returned its result instead of modifying a dictionary in-place. >>> x = {'a': 1, 'b': 2} >>> y = {'b': 10, 'c': 11} >>> z = x.update(y) >>> print(z) None >>> x {'a': 1, 'b': 10, 'c': 11}  How can I get that final merged dictionary in z, not x? (To be extra-clear, the last-one-wins conflict-handling of dict.update() is what I'm looking for as well.)


I just voted to close this question () as a dupe of this one (). The dupehammer came into play. The closed question now states:     This question has been asked before and already has an answer.   That statement is not true. The dupe has no answers. This looks like a bug to me.

The questions  and  were both marked as duplicates.   However, one of them has a different "marked as duplicate" notice below from the other. The first says "This question was marked as an exact duplicate of an existing question",  and the other one says "This question has been asked before and already has an answer".   I thought that maybe the messages were different because one of the questions is mine and the other one isn't as explained at , so I logged out and saw that there were still two different messages:            There are two differences that I noticed. First of all, the first one was closed by someone who had a gold badge in one of the question's tags, whereas the other one was closed by five normal users. Second of all, the first closure is much more recent than the other one. Is the reason to the different wording one of these? Or is there another reason?  Why are there two different duplicate notices? What is the difference between them?  This is not a duplicate of , as that question asks about the link to the target question above, while mine asks about the "marked as duplicate" notice below.


gksudo for Baobab Disk Usage Analyzer doesn't show /boot. I recently removed several old kernels. How can I verify that I've freed up space in /boot?     Backstory — I started spring cleaning because Ubuntu wasn't booting properly without workarounds. I diagnosed the error when my computer warned me that /boot was almost full. The warning opened Disk Usage Analyzer without root permission so /boot wasn't scanned. Now the analyzer can't seem to find the directory at all.  What I Did — After updating to most recent kernel, I removed old kernels one at a time with:   sudo apt purge linux-image-[VERSION].   When I was done, I updated grub2.  Each time the purge command said it would free up 0 Bytes of space. They are gone tho according to:   dpkg --list | grep linux-image

What is the command to find out how much disk space is being used/remaining?


Pardon my question but I am no astro-physicist.  If a black hole is a singularity, A.K.A. a single point in space-time which is infinitely small and which has an infinitely high density, can matter actually go "inside" a black hole?   My question is not if we can cross/go past the Event Horizon area, but rather what happens to the matter that crosses it?  Does the immense time dilation make it so that any matter that crosses the horizon actually freezes in space-time before even "touching" the singularity? (But that would only be for an external observer if I'm right?) Or is matter simply "crushed" into particles and molecules from the sheer strength of gravity?  I know I've asked like 3 questions in one, but if I had to pick the main question it would be this :   Can matter go inside a singularity?

The event horizon of a black hole is where gravity is such that not even light can escape. This is also the point I understand that according to Einstein time dilation will be infinite for a far-away-observer.  If this is the case how can anything ever fall into a black hole.  In my thought experiment I am in a spaceship with a powerful telescope that can detect light at a wide range of wavelengths.  I have it focused on the black hole and watch as a large rock approaches the event horizon.  Am I correct in saying that from my far-away-position the rock would freeze outside the event horizon and would never pass it? If this is the case how can a black hole ever consume any material, let alone grow to millions of solar masses.  If I was able to train the telescope onto the black hole for millions of years would I still see the rock at the edge of the event horizon?  I am getting ready for the response of the object would slowly fade.  Why would it slowly fade and if it would how long would this fading take?  If it is going to red shift at some point would the red shifting not slow down to a standstill? This question has been bugging me for years!  OK - just an edit based on responses so far.  Again, please keep thinking from an observers point of view.  If observers see objects slowly fade and slowly disappear as they approach the event horizon would that mean that over time the event horizon would be "lumpy" with objects invisible, but not passed through?  We should be able to detect the "lumpiness" should we not through?


I have a problem formatting a few equations the right way. I have equations with 5 variables which should be displayed among themselves. I tried it with the align environment  and ended up using a lot of tabs. Is there a prettier solution? I guess reducing the space between the tabs would help a bit.  \documentclass[12pt,a4paper]{article} \usepackage{amsmath}  \begin{document}  \begin{align*} 200 &x_R + &150x_C& + &200x_M& + &100 x_T& + &100x_L& &\le& 250000 \\ 150 &x_R+ &100x_C& + &100x_M& + &100x_T& &&&\le& 5000000 \\ 4 &x_R + &4x_C&  + &4x_M& + &4x_T& &&&\le& 20 000 \\ 15 &x_R + &10x_C& + &10x_M& + &15x_T& + &5x_L& &\le& 129600 \\ 2 &x_R + &1x_C& + &1.5x_M& + &1.5x_T& + &1x_L& &\le& 129600 \\  \end{align*}  \end{document}   EDIT:   \documentclass[12pt,a4paper]{article} \usepackage[german]{babel} \usepackage[latin1]{inputenc} \usepackage{amsmath} \usepackage{siunitx}     \begin{document}  \[ \setlength\arraycolsep{0pt}\renewcommand\arraystretch{1.1}   \begin{array}{*{4}{r<{{}}}l}     -4 u_1 + & 2u_2 - & 3u_3 + & 4 u_4\le & \num{9} \\     -3 u_1+ & 1u_2 + & 4u_3 + & 5u_4\le & \num{4} \\     \multicolumn{4}{r}{( u_1,\, u_2,\, u_3, \,u_4\ge{}} & 0)\\   \end{array} \] \end{document}

In LaTeX align, I'm struggling to align polynomial terms and assume there's an easy way to do it. But I cannot find the simple/elegant solution. What I would like is something like this:  x1 + x2 ______________ = 3  x1_______________+ x3  = 4  etc with more lines and variables (the underlines are just for space/alignment). Any help appreciated.  UPDATE Here is the solution I found:  \begin{alignat*}{7} 8x_1 &{}+ 4x_2 &{}+ y_1   &        &        &        &= 160     \\ 4x_1 &{}+ 6x_2 &          &{}+ y_2 &        &        &= 120     \\ x_1  &         &          &        &{}+ y_3 &        &= 34      \\ \phantom{{}+{}x_1}&{}+x_2&&        &        &{}+ y_4 &= 14      \\ x_1\geq0&x_2\geq0&y_1\geq0&y_2\geq0&y_3\geq0& y_4\geq0 \end{alignat*}   with result:


I have seen commands like this:  sudo apt-get upgrade -y    I would like to know the meaning of the -y flag and a reference for Linux command line flags in general.

I always see commands like this  apt-get -y install    What is the -y tag for and what is the difference between apt-get install with and without the -y tag?


Like the title says, I only remember the end of this. I think it was a film, but may have been an episode of something like The Outer Limits. I saw it on TV around 1999 (ish), and I think it was quite new then.  I've looked through all the episodes of the Outer Limits and haven't been able to find it, but maybe I missed it.  I remember that there was a spaceship with a number of crew aboard, and I think a robot. One of the crew was a drug addict. Something went wrong and the ship was going to explode, but there was only room for 2 (one woman, one man went) in the single escape pod. The other 2 (also one woman, one man) people on board (there may have been more earlier in the program) decided to overdose on the addict's drugs rather than just be blown up. You see the escape pod reaching some distance and see the main ship explode.  Then suddenly they 'wake up' in a room. The two people who overdosed are dead in that room, as are other people that had been on the ship who have been dead for a while. The 2 people left leave the room and find a long dead man guarding another door. They open the door and find what looked like a nuclear winter. ..And that's the end.  Any ideas on what this is?

I searched wide and far and couldn't come up with a title for a movie I watched somewhere around the mid-90ies up to early 00's as a rerun in late-night television (in Germany, specifically on Vox; but I'm sure it was an American movie to begin with).  Basically, what I remember from the story revolves around a crew in a space station or maybe space ship of some sort. Some crew members murder other crew members and there is some kind of door they are not supposed/unable to go through. Late in the movie they do go through the door and I'm pretty sure one of the first views is a skeleton of a dead security guard. It turns out the whole thing was some kind of simulation gone wrong and they find themselves to be in a (nuclear?) wasteland. And that's pretty much the revelation/wrap-up of the movie, as I recall it.  I would be delighted if somebody had any idea what movie this could be :) Thanks!  EDIT: The whole movie was in color and I think it was feature-length, not just 45 mins.


Let's say my party is attacking a dragon. I'm a Mastermind rogue who can use Master of Tactics to use the  as a bonus action if I'm within 30' of the dragon. Can I specify who in my party I'm giving the help to? Or will it necessarily be the next player who attacks the dragon?  Let's say the paladin in my party has his turn next and he decides to attack the dragon... but I'd really like to give advantage to the other rogue in my party who goes after the paladin. Can I specify that I'm helping the rogue?  If so, how would this be role-played to make some kind of logical sense? How would it play out?

When I use the , do I choose the monster to distract (and then the next ally to attack gets advantage) or do I choose the ally and the monster (so that only his attack against that target gets advantage)? Or something else?  Help [...] Alternatively, you can aid a friendly creature in attacking a creature within 5 feet of you. You feint, distract the target, or in some other way team up to make your ally’s attack more effective. If your ally attacks the target before your next turn, the first attack roll is made with advantage.


What's the difference between find . -name *gz and find . -name "*gz" I sometimes get the same result, other times I don't

find . -name *.rb   doesn't work on my ubuntu  I have to do  find . -name "*.rb"   to get it to work.  Why is that?


I'm new to Python. Trying install pip. All tutorials I saw say me to install setuptools first before installing pip. But I have read, that pip is a replacement for setuptools.  So, why I have to install setuptools first and only then I can install pip?

I've seen a good bit of setuptools bashing on the internets lately. Most recently, I read James Bennett's  post on why no one should be using setuptools. From my time in #python on Freenode, I know that there are a few souls there who absolutely detest it. I would count myself among them, but I do actually use it.  I've used setuptools for enough projects to be aware of its deficiencies, and I would prefer something better. I don't particularly like the egg format and how it's deployed. With all of setuptools' problems, I haven't found a better alternative.  My understanding of tools like  is that it's meant to be an easy_install replacement (not setuptools). In fact, pip uses some setuptools components, right?  Most of my packages make use of a setuptools-aware setup.py, which declares all of the dependencies. When they're ready, I'll build an sdist, bdist, and bdist_egg, and upload them to pypi.  If I wanted to switch to using pip, what kind of changes would I need to make to rid myself of easy_install dependencies? Where are the dependencies declared? I'm guessing that I would need to get away from using the egg format, and provide just source distributions. If so, how do i generate the egg-info directories? or do I even need to?  How would this change my usage of virtualenv? Doesn't virtualenv use easy_install to manage the environments?  How would this change my usage of the setuptools provided "develop" command? Should I not use that? What's the alternative?  I'm basically trying to get a picture of what my development workflow will look like.  Before anyone suggests it, I'm not looking for an OS-dependent solution. I'm mainly concerned with debian linux, but deb packages are not an option, for the reasons Ian Bicking outlines .


im having great trouble with my program. It's very simple, and i've completed it to the last step. Now though, I cant get the forloop to work and print out the name of movies.   insertMov creates three movie objects. The objects contain name, language and rating. I think it could be a problem with my scanner but im not sure. Thanks!  `import java.util.Scanner; public class MovieRecommendation{ Movie  [] movarr  = new Movie[3]; Scanner scanner = new Scanner(System.in); public void insertMov() {     movarr[0] = new Movie   ("Avengers", "english", 2013, "pg" );     movarr[1] = new Movie   ("Ironman", "english", 2008, "pg" );     movarr[2] = new Movie   ("fantastic 4", "english", 2005, "pg" );     }  public String main() {     insertMov();      System.out.println("Hey, I hear you want to watch a movie.");     System.out.println("what language do you want the movie to be in?");     String langInp = scanner.nextLine();     System.out.println("Thanks! Now, what rating would you like your movie to be?");     String ratInp  = scanner.nextLine();       System.out.println("Awesome :D Here are the movies Chosen for you");      for (int i = 0; i < movarr.length; i++ ){          if ( langInp == movarr[i].getLanguage() && ratInp == movarr[i].getRating()) {             System.out.println(movarr[i].getName());         }      }      return ("Feel free to use again"); }   }`

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


What is the difference between a 2x2x2 Split-Plot ANOVA and a 2-Way Repeated Measures ANOVA?

Is a "split plot" ANOVA with two factors identical to two-way ANOVA with repeated measures in one factor? if not, what is the distinction?


I have dell n4050 laptop. Do i have to install drivers after ubuntu installation? which version of ubuntu will support my laptop?

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


When an electron with E < V approaches a step in potential energy, the wave function will exponentially decay at the step, meaning there is still a finite possibility of the electron being found at x > 0:  My question: presumably the electron can't be found "inside" the step? So if it is found at X > 0, would it be found with E > V (i.e. above the step)? Or does such tunneling only have a meaning if the decaying wavefunction can reach the other side of the step?

I understand that if a particle approaches a finite potential barrier of height $V_0$ with energy $E < V_0$, there is still a finite probability of finding the particle on the other side of the barrier due to quantum tunneling.  My question is, since the wavefunction is nonzero inside the barrier region, is it possible to actually make a position measurement and locate a particle inside the barrier?  I mean, if we can say that "there is a nonzero probability that the particle is inside the barrier", surely this would suggest we can do so?  If not, why not? Am I understanding the whole wavefunction/probability distribution thing right?


The title bar in Firefox is gone. I need it back. Reasons: I need to easily enable/disable "Always on top". I need to be able to easily click drag FF by grabbing the title bar, not small space between tabs. How can I be fixing the Firefox to have normal title bar like other apps have in the Ubuntu? Like how Firefox used to be when it was good browser? What I have tried:  Googling a solution searching FF preferences right click on tab bar and random locations where the title bar used to be  System infos: OS: Ubuntu 20.10 Browser: Firefox 87.0 Beta 6

I used to use an extension to hide/show the title bar in Firefox, but since Firefox 57 was released most of the extensions were disabled.  In Chrome I just uncheck the option "Use system title bar and borders" and it's done.  Are there any ways to do that?


The texbook says that a return is representable as ^^M, I was wondering why is that, and any help on this will be highly appreciated!

Is there any use for the unescaped ^ in (La)TeX, when not in math mode? If not, I couldn't see why it's necessary to escape it.


I'm working with Xelatex 3.14159265-2.6-0.99991 (TeX Live 2014/Arch Linux), compiling my .tex file and getting a simple .pdf file.  I'm stuck on the following problem, occuring in a simple Japanese sentence. I want something like :     ABC せんつぶ まいたら ひとつぶに なあれ ひとつぶ まいたら   But all I get is (without any space between the Japanese words) :     ABC せんつぶまいたらひとつぶになあれひとつぶまいたら   I get the spaces only by using the \; "trick" but I would like to avoid it :  ABC せんつ\;ぶまいたら\;ひとつぶに\;なあれ\;ひとつぶ\;まいたら   I'm an absolute newbie and don't know how to handle this problem. Any help would be appreciated !    My .tex file :  \documentclass{article} \usepackage{xeCJK} \setCJKmainfont{Sazanami Mincho} \setmainfont{Sazanami Mincho} \usepackage[margin=4cm]{geometry} \usepackage{amsmath}  \begin{document} ABC せんつぶ まいたら ひとつぶに なあれ ひとつぶ まいたら \end{document}

This is my minimal working example:  \documentclass{article}   \usepackage{xeCJK} \setCJKmainfont{Batang}  \begin{document}         나는 남자를 이다 \end{document}   As you see, there are spaces between the Korean words. I compiled with XeLaTeX => PDF with XeTeX Version 3.1415926-2.5-0.9999.3 (MiKTeX 2.9) in TeXnicCenter. However there are no spaces in the outputfile. Help would be greatly appreciated.


Let $G$ be an abelian group. Show that the mapping $\phi:G\to G$ give by $\phi(x) = x^{-1}$ is an automorphism of $G$. Show that if $G$ were not abelian, then $\phi$ would not be an automorphism.   Okay so this is broken down into two cases;     case $1$: $G$ is abelian then $\phi$ is an automorphism   case $2$: $G$ is non-abelian then $\phi$ is NOT a automorphism   For case $1$: I want to show that $\phi(xy)=\phi(x)\phi(y)$, $\phi$ is $1$-$1$, and $\phi$ is onto, but I'm not sure how to do so.  For case $2$: I want to show that $\phi(xy)\ne\phi(x)\phi(y)$

I have trouble on this question: "Characterize the groups G for which the map $$\iota: G \to G$$ sending $$x \mapsto x^{-1}$$ for all $x \in G$, is an automorphism of $G$." From  post I have seen that $G$ must be abelian. Can anyone propose another characteristic of $G$ that I can derive from the given conditions besides abelian? Thank you so much!!


So a friend of mine will come visit soon and he has booked two hotels for his stay in Europe (same country, same city).  These hotels bookings are used to obtain the visa. So the first hotel won't change but we he may cancel the second to find another place to stay once arrived here (A more convenient hotel depending on where we want to spend time, probably closer to my place etc... it is a big city). But we are not sure yet.   Would it be a potential issue for the visa validity if the second hotel was changed once he made it here? (I am thinking of the when the immigration needs to contact him)

My route trip is Prague-->Berlin-->Vienna. I want to change the route to be Prague-->Berlin-->Paris.  Additionally, I already got my Schengen Visa, but after that I found a good deal in another hotel.    Can I change the first hotel I will visit before I travel?  If yes, is that going to cancel my visa or anything like that? Also I planned to go to Vienna and go back to my home from there. Can I change it and go to Paris instead?


Am unable to start VMWare player after upgrade to 13.04. Error: Before you can run Vmware several modules must be compiled and loaded into the running kernel. if i click on install nothing happens, kindly assist.

After upgrading to 13.04 I am unable to start VMWorkstation. I get the following message:     Before you can run VMware, several modules must be compiled and loaded   into the running kernel.      Kernel Headers 3.8.0-19-generic      Kernel headers for version 3.8.0-19-generic were not found. If you   have installed them in a non-default path you can specify the path   below.   Does anyone have any idea what to do next?  Ubuntu 13.04 64bit  If I direct the path to:  /usr/src/linux-headers-3.8.0-19-generic   I get the following message:     C header files matching your running kernel were not found.   Thanks  Additional:  As suggested I run this in terminal:  cd /lib/modules/$(uname -r)/build/include/linux   sudo ln -s ../generated/utsrelease.h   sudo ln -s ../generated/autoconf.h   sudo ln -s ../generated/uapi/linux/version.h   However, now I get the following:      Before you can run VMware, several modules must be compiled and loaded into the kernel    CANCEL / INSTALL   I INSTALL, the window closes and nothing happens.... Any ideas?  ADDITIONAL:  I installed this:  sudo apt-get install open-vm-tools open-vm-tools-dev open-vm-dkms open-vm-toolbox open-vm-tools-dev   And it all launched...  Many thanks for the suggestions and help... This is what I love about Ubuntu... it has a great helpful community... !   Note: Also found this which may help others too:   ADDITIONAL ERROR:  Could not open /dev/vmmon: Is a directory. Please make sure that the kernel module `vmmon' is loaded.  Failed to initialize monitor device.  Monitor settings all greyed out  RESOLUTION:   Re-installation of Nvidia Drivers


I tried to collapes the screen by pulling the thing onto the new screen. However, it isn't doing anything? I don't know why not. I also can't open the properties tab. When I push "n" it doesn't open the right tab. (I want to open the particles tab)

I can't find a way to close a view panel, in particular the horizontal at the bottom, is pretty useless to me at this moment.


I have the following code   template<typename VP,bool b>   class ValueProcessor{     template<typename Access,typename X> void processValue(X& x){}   };     template<typename VP>   class ValueProcessor<VP,true>{   public:     template<typename Access,typename X> void processValue(X& x);   };    template<typename VP>     template<typename Access,typename X>    void ValueProcessor<VP,true>::processValue(X& x){     class Updater{       ValueProcessor<VP,false> valPro;       X x;     public:       void operator()(){         valPro.processValue<Access,X>(x);       };     };   }  but it fails with this error     source>: In member function 'void ValueProcessor<VP, true>::processValue(X&)::Updater::operator()()': <source>:23:32: error: expected primary-expression before ',' token    23 |      valPro.processValue<Access,X>(x);       |                              ^  How can I refer to Access from the inner class?

In templates, where and why do I have to put typename and template on dependent names? What exactly are dependent names anyway?    I have the following code:  template <typename T, typename Tail> // Tail will be a UnionNode too. struct UnionNode : public Tail {     // ...     template<typename U> struct inUnion {         // Q: where to add typename/template here?         typedef Tail::inUnion<U> dummy;      };     template< > struct inUnion<T> {     }; }; template <typename T> // For the last node Tn. struct UnionNode<T, void> {     // ...     template<typename U> struct inUnion {         char fail[ -2 + (sizeof(U)%2) ]; // Cannot be instantiated for any U     };     template< > struct inUnion<T> {     }; };   The problem I have is in the typedef Tail::inUnion<U> dummy line. I'm fairly certain that inUnion is a dependent name, and VC++ is quite right in choking on it. I also know that I should be able to add template somewhere to tell the compiler that inUnion is a template-id. But where exactly? And should it then assume that inUnion is a class template, i.e. inUnion<U> names a type and not a function?


A simple for loop in Unix would be:  for FILE in $BASE_WORK_DIR/*.pdf    do      echo $FILE    done   This will echo all .pdf files inside BASE_WORK_DIR directory.   What if BASE_WORK_DIR contains sub directories as well which also contain the pdf file.  In that case how can I design my for loop to take all pdf files from BASE_WORK_DIR as well as sub directories of BASE_WORK_DIR ?

I wrote the following script to diff the outputs of two directores with all the same files in them as such:  #!/bin/bash  for file in `find . -name "*.csv"`   do      echo "file = $file";      diff $file /some/other/path/$file;      read char; done   I know there are other ways to achieve this.  Curiously though, this script fails when the files have spaces in them.  How can I deal with this?  Example output of find:  ./zQuery - abc - Do Not Prompt for Date.csv


From the desktop, any new question has a list of suggested duplicates between the title and the body. From personal experience, this has stopped me from posting several duplicate questions.  Can we get this feature in the iOS app?  Perhaps replace the body input area with the list while the title is focused. You can still see the text in the rendered area to the right, so that's not a problem.

When asking a question through the iOS app (v. 0.1.24), the question just gets posted without any sort of chance to review similar questions. (This is shown on the iOS web app and desktop browsers on the full site in the right sidebar as you edit any question before posting it.)  Would it be possible to have new questions saved as drafts (ideally to the servers), and then present a second sheet with potential duplicates?  This would let someone compose a question and then encourage them to make sure it's not already machine matched with a similar post before it actually gets posted to the site.


I have a Django model say:  class MyOperation(models.Model):     name = models.CharField(max_length=100)      def my_method(self):         pass   I want to be able to add, from a different Django app, a new method to this class.   I tried to do this from a different app module called custom.py:  from operations.models import MyOperation  def op_custom(test):     print "testing custom methods"  MyOperation.op_custom = op_custom   However this does not seems to work, in runtime the method does not exists.  Is this the way to modify the definition of a class from a different django application? Is there a better way to do it?  Thanks

I've read that it is possible to add a method to an existing object (i.e., not in the class definition) in Python.   I understand that it's not always good to do so. But how might one do this?


I have a lot of projects. And for each project, I have two files in them: setup and serve. Each developer follows these simple three steps to start coding:  git clone ... ./setup ./serve  The problem is that ./setup is not easy to type. And since this is a microservice architecture with a lot of repositories, ./setup and ./serve would be used frequently. How can I make ubuntu understand that any time I write setup anywhere I mean there is a file called setup and you should run it. This way developers would only configure their machines once, and then start coding using clone,setup,serve paradigm.

I'd like to know if there is a way to run  program/shell script without typing full path:  /opt/idea/bin/idea.sh


$$\int x(x^2+2)^4\,dx $$  When we do this integration with u substitution we get $$\frac{(x^2+2)^5}{10}$$ as $u=x^2+2$  $du=2x\,dx$ $$\therefore \int (u+2)^4\,du = \frac{(x^2+2)^5}{10} + C$$   Although when we expand the fraction and then integrate the answer we get is different:  $x(x^2+2)^4=x^9+8x^7+24x^5+32x^3+16x$ $$\int x^9+8x^7+24x^5+32x^3+16x \,dx$$  we get  $$\frac {x^{10}}{10} +x^8+4x^6+8x^4+8x^2 + C$$  For a better idea of the questions, let's say the questions asks us to find the value of C when y(0)=1  Now,  $x=0$  $$\frac {0^{10}}{10} + 0^8 + 4(0)^6 + 8(0)^4 + 8(0)^2 + C = 1$$ $$\therefore C= 1$$ AND $$\frac {(0+2)^5}{10} + C= 1$$ $$\therefore \frac {32}{10} + C = 1$$ $$\therefore C = 1 - 3.2 = -2.2$$

Question:  Is it possible to get multiple correct results when evaluating an indefinite integral?  If I use two different techniques to evaluate an integral, and I get two different answers, have I necessarily done something wrong?    Often, an indefinite integral can be evaluated using different techniques.  For example, an integrand might be simplified via partial fractions or other algebraic techniques before integration, or it might be amenable to a clever substitution.  These techniques give different results.  For example, looking over a few other questions on MSE:      From : evaluate $$ \int x(x^2+2)^4\,\mathrm{d}x. $$    Via the substitution $u = x^2+2$, this becomes $$ \int x(x^2+2)^4\,\mathrm{d}x       = \frac{1}{10}x^{10} + x^8 + 4x^6 + 8x^4 + 8x^2 + \frac{32}{5} + C.     $$ However, multiplying out the polynomial and integrating using the power rule gives $$ \int x(x^2+2)^4\,\mathrm{d}x       = \frac{1}{10}x^{10} + x^8 + 4x^6 + 8x^4 + 8x^2 + C    $$     From :  evaluate   $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x. $$    Simplifying the integrand using partial fractions then integrating gives $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x       = \frac{-2}{(x+1)} - \ln|x+1| + C.    $$ Via integration by parts, we get $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x       = \frac{x-1}{(x+1)} - \ln|x+1| + C.    $$     From : evaluate   $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x. $$    Using the substitution $u = \sec(\pi x)$, this becomes $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x       = \frac {\sec^2(\pi x)}{4\pi} + C.    $$ Using the substitution $u = \tan(\pi x)$, this becomes $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x       = \frac {\tan^2(\pi x)}{4\pi} + C.    $$


I've got a form that people can fill out and the results of the form are displayed on a page. The form is limited to 2000 characters, however there's nothing limiting how many line breaks there can be, so someone could just put one character per line and get 2000 line breaks, which clutters up the page pretty badly. I'm looking to limit the number of lines that they can type into the textarea so the limits are 2000 characters or 40 lines, whichever comes first.  I would also need this to be protective of people pasting large amounts of text into the form as well. I looked at a lot of other posts about this but none of the answers worked when I tried them. Thanks!

I'm looking for a javascript that can limit the number of lines (by line I mean some text ended by user pressing enter on the keyboard) the user is able to enter in textarea. I've found some solutions but they simply don't work or behave really weird. The best solution would be a jquery plugin that can do the work - something like , but it should be able to limit text line count not character count.


Let random K-dimensional variable $\mathbf{v} \sim \mathbf{Dir}(\mathbf{\alpha})$. I want to find a one-to-one mapping $f(\cdot)$ such that $f(\mathbf{v})$ is a random variable on whole $R^{K-1}$.

I have data on movement behaviours (time spent sleeping, sedentary, and doing physical activity) that sums to approximately 24 (as in hours per day). I want to create a variable that captures the relative time spent in each of these behaviours - I've been told that an isometric log-ratio transformation would accomplish this.   It looks like I should use the ilr function in R, but can't find any actual examples with code. Where do I start?  The variables I have are time spent sleeping, average sedentary time, average average light physical activity, average moderate physical activity, and average vigorous physical activity. Sleep was self-reported, while the others are averages from valid days of accelerometer data. So for these variables, cases do not sum to exactly 24.   My guess: I'm working in SAS, but it looks like R will be much easier to use for this part. So first import data with only the variables of interest.  Then use acomp() function. Then I can't figure out the syntax for the ilr() function. Any help would be much appreciated.


I'm writing a webpage on which I need to have a div wrapper containing two divs (one toolbar and one editor). The toolbar heigth is not known, and I need to make the editor div fill all the remaining space within the wrapper.  The solution need to be full HTML + CSS.

   For the CSS:   #wrapper {   position: absolute; // I need this, I can't remove it   top: 0; // should stick on the top   height: 100%; // should span across the whole height   width: 100%; // Can be anything 0 ≤ width ≤ 100% }  #editor {   width: 100%; // fill the whole horizontal space   height: 100%; // if I do so, the div gets too high and the #editor goes beyond the wrapper limit }   Here's a jsfidlle to play with

I am working on a web application where I want the content to fill the height of the entire screen.  The page has a header, which contains a logo, and account information. This could be an arbitrary height. I want the content div to fill the rest of the page to the bottom.  I have a header div and a content div. At the moment I am using a table for the layout like so:  CSS and HTML    #page {     height: 100%; width: 100% }  #tdcontent {     height: 100%; }  #content {     overflow: auto; /* or overflow: hidden; */ }

...

...

     The entire height of the page is filled, and no scrolling is required.  For anything inside the content div, setting top: 0; will put it right underneath the header. Sometimes the content will be a real table, with its height set to 100%. Putting header inside content will not allow this to work.  Is there a way to achieve the same effect without using the table?  Update:  Elements inside the content div will have heights set to percentages as well. So something at 100% inside the div will fill it to the bottom. As will two elements at 50%.  Update 2:  For instance, if the header takes up 20% of the screen's height, a table specified at 50% inside #content would take up 40% of the screen space. So far, wrapping the entire thing in a table is the only thing that works.


I am running Ubuntu 16.04. Is it possible to set up wifi hotspot from my machine so that I can use internet on my mobile devices?  It may be noted that I am using laptop.

Although many questions have already been asked regarding WiFi hotspot, I didn't get any of the solutions working for me.  I connect to the Internet using a 3G Dongle of Huawei 3772 (Vodafone). The connection type is Mobile Broadband connection. I have to share this Internet connection with my other devices like mobile phones and laptops.  How can I create a WiFi hotspot connection for this connection.  I am using Ubuntu 12.04 LTS.  I would like to note that I have already tried some help links from Ubuntu but, they are so confusing that I could not understand them.


On some sites the bar at the top will move down with you when you move down the page. I think that something like this might look nice on Stack Exchange.  What I mean is for this bar:    To move down the page with you as you move down the page, and up when you move up the page so that you can always access it however far down the page you are. Is this something that SE might implement?

In Excel, the window can be frozen in place in such a way that you can always see the name of the column even though you go way down below the 'fold' of the screen.  On SE, when you scroll, the whole page goes up (or down). This means the top navigation bar is scrolled off screen. I'm not sure if it would be a good idea or not to fix the top navigation to the top of the screen and let the rest of the content scroll.  What do you think about this, in terms of pros and cons?  [Update]  With the new Top navigation bar, kudos to the design team, I think this question becomes relevant again. I'm aware of the busload of downvotes, but still.  The top navigation bar doesn't occupy much space and has two notification areas:   Inbox Achievements   Having these two notifications visible at all times would be nice, IMO.  [Update]  I've just noticed that I haven't used the word "optional" in this discussion... My bad. In Excel, the Freeze function is controlled by the user. You can optionally Freeze part of the interface, and you can eliminate the Freeze at will.


Should I use singular countable nouns or plural countable nouns with no along with the word except?   There is no scientist who is as renowned as Einstein except Stephen Hawking. There are no scientists who are as renowned as Einstein except Stephen Hawking. I have no book except this red one. I have no books except this red one.   I know it is more natural to use no with countable plural nouns in general. So we would generally say "There are no scientists in the hall." and "I don't have any books in my house." But when I use no with except the problem arises. Can anyone please explain?

Can I use plural nouns after any in the following sentences?   1- We don't have any options except to go there.   2- I don't have any friends except John.   3- I didn't meet any officers except him.


Find all prime numbers $p$ and $q$ such that $p^{q+1} + q^{p+1}$ is a perfect square.  Number theory problems like these are always difficult for me. So please insert the topics under which this problem has been asked and also I welcome your solution.

How can one find all primes $(p,q)$  such that $p^{q+1}+q^{p+1}$ is a perfect square   I considered it $\mod 2$ and found a trival solution .  Im curious about an eventual answer Diophantine equations are extremely hard. This seems harder than IMO Q2 of this year .  edit1: I think one should consider it $\mod 4$ .


I'm trying to add some unit tests to make sure that the correct Error is being thrown (my function either throws KeyError or RuntimeError). I've tried assert func(bad_param) == KeyError and assert isinstance(func(bad_param), KeyError) but neither of these are correct, how am I supposed to write unit tests for this / what's the correct way to assert that this function, when passed a bad parameter, will raise the correct Exception? EDIT: I'm NOT using the unittest library, I'm asking about purely the assert function that comes with Python std lib ()

How does one write a unittest that fails only if a function doesn't throw an expected exception?


I'm making a model in Blender and then I think I pressed something on my keyboard and then my hierarchy went missing! How can I bring it back again?  Thanks!

I'm stuck in full screen in the node editor. Escape isn't working, and I have no menus and no idea how to leave except to quit Blender and reopen the program.


I have to vera long tables underneath eatchother. Both don't fill up the whole text width, the second even less so. I have no idea why they do that since all other tables made with longtable automatically took up the same width as the text. I've read the documentation on the longtable package but have no idea what to put instead of the dots in \begin{longtable}{@{\extracolsep{...}}...}. Do I have to calculate something?

\usepackage{longtable}  \begin{landscape} \begin{table}[!htb] \centering \resizebox{\linewidth}{!}{% \begin{longtable}{|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|}  % Table here  \end{longtable}% }% \end{table} \end{landscape}   I am unable to get the table to span over multiple pages while fitting the table to the width of the landscape page. Would you know how to do this, please let me know.


I have a script to reorganize my directory structure that contains:  files=./*"$pattern"I{"$ifirst".."$ilast"}.ext cp ${files} ../"$pattern"/"$i"/   When I run the script, I get an error:  ./*S6I{001..129}.ext: No such file or directory   However, if I echo the command and then copy/paste it into the terminal I get the behavior I'd expect:  cp ./*S6I{001..129}.ext ../S6/1/   Why would this not run correctly from the script?

Can I use variables inside {} expansion without appealing to eval? If so, how?  This doesn't work:  $ touch 1.foo 1.bar $ ls 1.{foo,bar} 1.bar  1.foo $ extensions=foo,bar $ ls 1.{$extensions} ls: cannot access 1.{foo,bar}: No such file or directory   It works with eval:  $ eval ls 1.{$extensions} 1.bar  1.foo


I cannot use cd anymore when using it in a bash script   [~/Downloads] # cat cd-backward #!/bin/bash cd ..  [~/Downloads] # ./cd-backward [~/Downloads] #   I should move to ~ at the last line.  cd works perfectly in terminal strangely. Nothing happens also when I run bash -c 'cd Download for instance.

I just want to write a script which changes my directory.  I put the below commands in the file /home/alex/pathABC  #!/bin/sh cd /home/alex/Documents/A/B/C echo HelloWorld   I did   chmod +x pathABC   In the Terminal, while in /home/alex, I ran ./pathABC, but the output is just HelloWorld and the current directory is not changed.  So what is wrong?


EDIT: I have reviewed the "Duplicate claim" and to be frank, it is not answering my query, like most of my questions, the existing duplicate question do not answer my query.  Besides that, I am dumping Ubuntu as I am sick and tired of the persistent issues with it, things working one day then not the next and everything breaking after each update and I do believe the main reason I can't update is due to my system being knobbled :)   So enough is enough, I have found a stable version of software that does not contain spyware like Ubuntu does.  Happy smoking guys.  Ciao.    I have asked a couple of times on how to go about this cloning of a drive, I have been advised to use dd or cat but neither work, well dd worked but not as expected. The command I used was:   dd if=/dev/sda | gzip -c > "/media/mark/Seagate Expansion Drive/ssd.img.gz"   The result was an unusually large container (51.3GiB) for a very small image file (3.9GiB) and it took more than 10 hours to do. I was able to copy data from the drives with copy and paste in about 45 Minutes before I unmounted for the drive image to be completed.  So, to set things straight from the outset...  Drive to be copied - SSD drive, 64GB on the tag, has two partitions, is referenced as /dev/sda/ with /dev/sda2 as the boot partition NOT MOUNTED  Drive to have image dumped to - USB HDD, 2TB on the tag, has one partition with 144MB buffer at the end on /dev/sdc1 IS MOUNTED  The drives copied from and copied to are not used as a boot drive, the boot device/partition is on /dev/sdb1 (which is an SD Card) and neither device is used during the process. Yes the sda drive is unmounted, had to repeat that point as the first time around it may have been missed.  Each time I am told that I should use dd if=/dev/sda | gzip -c > "/media/mark/Seagate Expansion Drive/ssd.img.gz" the image results in a very strange file that is 51.3GiB and in that file is a 3.9GiB file thats the image!?!?! Ummm the drives are nearly full!  Each time I try to do this using ZIP which is what I want and thats so I can access in Windows should I need to do a blanket reinstall and pull the files I need from the ZIP file, however when I use dd if=/dev/sda | zip "/media/mark/Seagate Expansion Drive/ssd.img.zip" I get a message that the program has nothing to do!  I have tried the same with the cat command and that results in errors stating that "nothing to do!" and despite pointing out my needs, I get answers that would over write the existing partition, not what I am looking to do.  Yes "I have the ZIP libraries", yes "the drive to write to is mounted", no "the source drive is not mounted", I have no storage issues, so the ZIP can be uncompressed format.  Can someone help please?  ** EDIT **  Excuse me for getting frustrated BUT does Ububntu have ANY software that works?  My problem is very simple to follow, I have an SSD that is 64GiB in size, it is about 98% full.  I have followed examples online and by advice from here in askubuntu and everyone posts stuff like I have previously posted.  The image file made using dd resulted in a 51.3GiB file called ssd.img.gz, within that gz archive a file called ssd.img resides and it is 3.9GiB in size.  NOW FORGET ALL THAT ABOUT THE CONTAINER...  I want to make an image of a drive that can later access in a ZIP program, I have gzip and zip libraries, my preference is ZIP because windows can read ZIP files without any external program.  How can I make a useable drive image that I can verify as being the same so I can then repair / break the drive with the confidence that I can restore the contents as it once was.  How can I do that please?

I created yesterday a drive image using GZip.  I opened the 51.3 GiB file named ssd.img.gz to see one icon thats a package of 3.9 GiB, yes, thats THree point Nine Gigabytes in size and has the name of the image as ssd.img  That does not seem right to me, has the image creation worked or not?  Yes the drives have data and an operating system on it.  Should I have used cat instead? only I did and it kept on saying that it had nothing to do.  Would using the | zip instead be a better option?    ** EDIT **  The command used was:  mark@zotac:~$ sudo -l Enter password:<entered password to get in to root> root@zotac:~# dd if=/dev/sda | gzip -c > "/media/mark/Seagate External Drive/ssd.img.gz   the terminal spent the best part of 10 Hours at building the image, something in itself that I also found suspect, why so log when copying the files to a folder that I wanted, some 40GiB took 45 minutes...  The source drive /dev/sda had no mounted partitions.     ** EDIT **  Just to clarify, I am trying to make an image of the drive to back up later if things go wrong with a repair, the drive itself needs to be a file on a drive as the target drive partition is using almost all of the drive, the partitions can't be resized on it without formatting it and I am not about to lose 1.4TB of data.   So the dd if=/dev/sda of=/<target> isn't what I need, what I do need is an image of the drive that I can restore the image from to the drive should the repair go wrong.  So what command do I use, dd or cat? Why does | zip keep telling me it has nothing to do when used with cat but no error or warning with dd


I'd like to see the number of people I reached on a specific tag compared to others in my country. Found how to . How can I compare using the number of people reached instead of reputation?

I know the new profile design hasn't been updated for  on the network yet, so maybe this is a bit too early. Nonetheless, please include the "People Reached" data in  at your earliest convenience. Also, I was just made aware that users helpful flag counts are now publicly displayed on their  towards the top-right, underneath the people reached stat. So please include this data in SEDE as well.


I'm new to python and am trying to modify a single value in a list of lists.  I come from java experience.  I am writing code for a chess application to familiarize myself with python.  board is a list of lists that contains all the pieces that exist on the board.    def updateMoves(self):     for i in range(self.getY()+1,col,1):         if board[self.getX()][i] != None:             self.canMove[self.getX()][i]=False             break;         else:             self.canMove[self.getX()][i]=True  def printMoves(self):     s=""     for i in range(row):         for k in range(col):             if self.canMove[i][k]==True:                 s=s+"T,"             else:                 s=s+"x,"         print(s)         s=""   GetY and X return a value stored on the piece of it's current position on the board(in this case the piece is in 2,2).  The values in my list are started out as all false this code results in the canMove list(local to the class) looking like this: (x is false)  x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T, x,x,x,T,T,T,T,T,   I decided to put breakpoints in, and on each loop of the array it changes the entire column to True.  Any idea why this might be? I'm assuming its a syntax issue, but can't find anything in my google searches.

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


My Imports: # Importing modules  import numpy as np  import pandas as pd  import os import matplotlib.pyplot as plt import cv2  from keras.utils import to_categorical from keras.layers import Dense,Conv2D,Flatten,MaxPool2D,Dropout from keras.models import Sequential  from sklearn.model_selection import train_test_split  My Code: np.random.seed(1)   train_images = [] train_labels = []  shape = (108,108)  label_path = 'Beer/ModelSet/'  train_labels.append('miller_lite') train_labels.append('stella_artois') train_labels.append('michelob_ultra') train_labels.append('belgian_blue')  for folder in os.listdir(label_path):     for files in os.listdir(label_path+folder):         img = cv2.imread(os.path.join(label_path,folder,files))         train_images.append(img)   train_labels = np.asarray(pd.get_dummies(train_labels).values)  train_images = np.asarray(train_images)   x_train, x_val, y_train, y_val = train_test_split(train_images, train_labels, random_state=1)  The part that fails     x_train, x_val, y_train, y_val = train_test_split(train_images, train_labels,  random_state=1)  The reason it fails ValueError: Found input variables with inconsistent numbers of samples: [20000, 4]  My Error: 2020-08-03 23:47:11.117431: I tensorflow/stream_executor/platform/default/dso_loader.cc:48] Successfully opened dynamic library libcudart.so.10.1 Traceback (most recent call last):   File "/Attempt-2.py", line 40, in <module>     x_train, x_val, y_train, y_val = train_test_split(train_images, train_labels, random_state=1)   File "python3.8/site-packages/sklearn/model_selection/_split.py", line 2127, in train_test_split     arrays = indexable(*arrays)   File "python3.8/site-packages/sklearn/utils/validation.py", line 293, in indexable     check_consistent_length(*result)   File "python3.8/site-packages/sklearn/utils/validation.py", line 256, in check_consistent_length     raise ValueError("Found input variables with inconsistent numbers of" ValueError: Found input variables with inconsistent numbers of samples: [20000, 4]  The Goal: Create a classification model that distinguishes between 4 different brands of beer bottles. MillerLite,StellaArtois,MichelobUltra, and BelgianBlue. Background Note: I have never had any practical/work experience with either software engineering, data science, software development, machine learning etc. I am just a student messing around for my own amusement/fun. The Question: How exactly do I fix this? I understand the problem is that matrix x is not the same size as matrix y. X is 20000 images of size 108,108 and 3 channels RGB. Y is the label matrix: [[1 0 0 0][0 1 0 0][0 0 1 0][0 0 0 1]] in order to split into train/test images the error says I need to have the same len/size array/matrix for both x and y.


I was reading Fantastic Beasts and Where to find them, and I found this quote:  “Werewolves spend most of their time as humans (whether wizard or Muggle).”  (Fantastic Beasts and Where to Find Them) Does this mean, if a muggle is bitten by a werewolf, and somehow survives (rescued by wizards, then had their memory modified), that they will become a werewolf? I may make a second question on this topic regarding how the wizarding world would remain hidden to this muggle, if they do indeed become a werewolf. I am looking for canon answers based on JKR interviews, the books, or simply your own canon-based speculation!

We  that, in all likelyhood, in HP universe, Lycanthropy is a contagion that has magical properties, and is not merely a virus (despite being a metaphor for one as intended by JKR).  As such, is there any canon evidence for what would happen should an HP werewolf bite and try to infect a Muggle? More specifically, would said Muggle have a chance of turning into a werewolf?


Compute the maximum of $|f(z)|$ when $|z| \leq 1$ and $f(z)=\sin (z)$  So since $f$ is holomorphic on  $|z| \leq 1$, we know we'll find the max of $|f(z)|$ on $|z|=1$.  So:  $|f(z)|=|\sin(z)|=|\frac{e^{iz}-e^{-iz}}{2i}|=|\frac{e^{iz}}{2i}-\frac{e^{-iz}}{2i}|\leq |\frac{e^{iz}}{2i}|+|\frac{e^{-iz}}{2i}|=\frac{|e^{iz}|}{2}+\frac{|e^{-iz}|}{2}=\frac{e^{|iz|}}{2}+\frac{e^{|-iz|}}{2}=e$   I'm not so certain about this solution. Is there another way? Is using the triangle inequality safe when looking for a maximum?

Maximum of $|\sin(z)|$ as $\{z: |z| \leq 1 \} $  So according to the Maximum Principle, the maximum is when $|z|=1$. I tried using the fact that $\sin z= \dfrac {e^{iz}-e^{-iz}}{2i}$, but didn't know how to continue from there. Setting $z=e^{it}$ doesn't help much.  I saw this question was answered before, however the answer uses hyperbolic functions ($\sinh, \cosh$) which I haven't actually studied.  Thanks in advance for any assistance!


Just bought a house no basement have a crawl space the dryer vent discharges into the crawl space . The furnace is also near by. ? Good or bad .

We have a crawl space with a combination of sandy and clay soil in it.  The crawl space is about 3' deep.  To eliminate a long dryer vent run, I'd like to vent the dryer directly into the crawl space.  We have vents built into the foundation that I open each spring and close in the fall.  Will this help dissipate the moisture enough to prevent mold?


How do you think names that have the plural "s" should be pronounced when they get the apostrophe? I researched this on the web and I couldn't find any very reliable results. For example, how should these three words be pronounced?  The Beatles'  Red Hot Chili Peppers'  Mr. Jingles'   Context: In case you don't know, The Beatles are a band, Red Hot Chili Peppers are also a band. "Jingles" is a last name that includes the plural "s". It is not a band name. I know that normally, when a plural word gets the apostrophe, you don't make a second /ɪs/ or /ɪz/ sound. For example, you don't say, /ɡɑɪzɪz/ when you say  "guys' ". But I think we might pronounce another /ɪs/ or /ɪz/ when we say the words I gave because names like "The Beatles" represent one singular band while they also represent the people in the band. When you say "Mr. Jingles" also it represents one person. So I thought it may be correct to pronounce the example words I gave as, "The Beatles + /ɪz/", "Red Hot Chili Peppers + /ɪz/", "Jingles + /ɪz/".

If I want to use the plural of "moderator" and also add the apostrophe plus S, how do I pronounce it? How do native speakers pronounce it?  Moderators = moderatorz Moderators's = moderatorziz or just moderatorz?  A sentence is:  "I always thought that moderators's decisions seemed fairly arbitrary."   I guess moderatorziz is correct but it sounds weird to me. Do native speakers pronounce it as moderatorziz?


Why in this code i can't swap StringBuffer's?   public static void main(String[] args) {      StringBuffer a = new StringBuffer("One");      StringBuffer b = new StringBuffer("Two");      swap(a, b);      System.out.println("a is " + a + "\nb is " + b);  }  static void swap(StringBuffer a, StringBuffer b) {     a.append(" more");     b = a; }

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


Question - Prove that for any even positive integer $n, n^{2}-1$ divides $2^{n !}-1$    Proof: Let $m=n+1 .$ We need to prove that $m(m-2)$ divides $2^{(m-1) !}-1$   Because $\varphi(m)$ divides $(m-1) !$   we have $\left(2^{\varphi(m)}-1\right) |\left(2^{(m-1) !}-1\right)$   and from Euler's theorem, $m |\left(2^{\varphi(m)}-1\right) .$ It follows that $m |\left(2^{(m-1) !}-1\right) .$  Similarly $(m-2) |\left(2^{(m-1) !}-1\right) .$ Because $m$ is odd, gcd $(m, m-2)=1$ and the conclusion follows.  I just want to understand how they write  Similarly $(m-2) |\left(2^{(m-1) !}-1\right) .$

Prove that for any even positive integer $n$, $n^2-1 \mid 2^{n!}-1$     This is from a book. They have given the proof. But I didn't understand it well. I am looking for a simpler proof. Or it will be helpful if someone explain this a little bit more - Proof: Let $m = n+1$ then we need to prove that $m(m-2) \mid 2^{(m-1)!}-1$. Because of $\phi(m) \mid (m-1)!$, we have $2^{\phi(m)} -1 \mid 2^{(m-1)!} -1$. And from Euler's theorem, $(m-2) \mid 2^{(m-1)!}-1$. Because $m$ is odd, $gcd(m,m-2)=1$ and the conclusion follows.


Can someone please explain how python assigned the value below to y. I understand how the function works but I do not understand how the function call a(10) assigns its value y.   def outside(x):     def inside(y):         return x ** y     return inside  a = outside(2)  a(10)

I am trying to figure out this:  c = 1 def f(n):     print c + n  def g(n):     c = c + n  f(1) # => 2 g(1) # => UnboundLocalError: local variable 'c' referenced before assignment   Thanks!


I don't have any package installations running, yet I get the following error when I try to install a DEB package. I thought about rebooting the system but that could corrupt the database. And it has happened before.  sudo dpkg -i slack-desktop-2.1.2-amd64.deb  dpkg: error: dpkg status database is locked by another process     sudo apt-get update Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease Hit:2 http://dl.google.com/linux/chrome/deb stable Release Hit:4 http://archive.ubuntu.com/ubuntu xenial InRelease Get:5 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [95.7 kB] Hit:6 http://archive.ubuntu.com/ubuntu xenial-backports InRelease Hit:7 http://archive.ubuntu.com/ubuntu xenial-security InRelease Get:8 http://archive.ubuntu.com/ubuntu xenial-updates/main Sources [188 kB] Get:9 http://archive.ubuntu.com/ubuntu xenial-updates/universe Sources [94.2 kB] Get:10 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [387 kB] Get:11 http://archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages [383 kB] Get:12 http://archive.ubuntu.com/ubuntu xenial-updates/main Translation-en [147 kB] Get:13 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [326 kB] Get:14 http://archive.ubuntu.com/ubuntu xenial-updates/universe i386 Packages [323 kB] Get:15 http://archive.ubuntu.com/ubuntu xenial-updates/universe Translation-en [113 kB] Fetched 2,058 kB in 5s (360 kB/s)                                 E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?

I just wondered if somebody could tell me what this means:  E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem. reidsr@ubuntu:~$ sudo dpkg --configure -a dpkg: error: dpkg status database is locked by another process reidsr@ubuntu:~$    How do I run sudo dpkg --configure -a  manually?


$\int e^x \sqrt{1+e^{2x}}dx$  It's probably been answered somewhere, but I havent found it so far so I decided to post it as a question (if it has been answered point me in the right direction and I will delete the question.  What I have tried:   Put it into mathematica, got a relatively simple answer: $$\frac{1}{2} (e^x \sqrt{1+e^{2x}}+\sinh^{-1}e^x)$$ Dont know how to get there! Obviously I tried $e^x = u$  substitution, ended up with $\int \sqrt{1+u^2}du$. From here I am not really sure what do to, I tried another substitution of $u=\cosh t$, but to be honest I am very unfamiliar with hyperbolic trig:   $$u=\cosh t \implies du=\sinh t~dt$$  $$\int \sinh t\sqrt{1+\cosh^2t} ~ ~dt$$ And i believe this is the same as $\int \sinh^2 t ~ ~dt$? Once again, I am not too sure about this because I don't know much about hyperbolic trig.   From here I don't know where to go (don't even know if my working so far is right)..

How do we solve (i.e. get the closed form of) $\int \sqrt{1 + t^2} dt$ ?   shows the closed form of it but not the steps in solving it.  I think I need some algebraic trick..   I thought of some hyperbolic functions and their derivatives and equalities:  If I make $ t = \sinh x$, then I can reduce the integral to  $$ \int \cosh ^2 x dx $$ though I'm not sure if this is valid. But from here, I cannot go on evaluating the integral...


Firstly I think (please confirm) the notation $g(x)$ (for $x \in \{1,2,3,4\}$) caters to the position $y \in \{1,2,3,4\}$ such that $x \to y$.  Is it true that $g((12)) = (g(1) g(2))$? I can not wrap around my head if this is even defined. If so, an explanation would be really helpful. How is $g(12)(34)g^{-1} = (g(1) g(2))(g(3)g(4))$ where $g \in S_4$?  I am fine if hints or heuristics are provided so I can think how it works. A definition for $(1)$ would enable me to think $(2)$.

I have heard that two permutations are conjugate if they have the same cyclic structure. Is there an intuitive way to understand why this is?


I have a brand new 10.1 inch tablet, made in china. The screen doesn't respond to touch as much as it should, a few other little things and I can't work out some of the onscreen operating icon/button things. The resellers suggested I start with Android Central Forums, as this is the only Android devise they sell so they don't know the answers. I joined up with A.C.Forums, but can't work out how to post. Help and/or advice would be very much appreciated. Thanks

My HTC Evo 3D sometimes doesn't react when i press certain areas of the screen. I noticed it happens mostly on the part where the letter 'e' is, when i'm holding the phone in landscape mode.  So, i did a factory reset, wiped out SD card as well during the factory reset, and the problem still persists.  It sometimes happens for a certain period of time, and it starts to work after a while.  I did a line drawing test, and on some places it doesn't draw the line correctly (it is continuos but it's drawn with sharp angles, i don't know how to explain it better).  I read somewhere it is most probably a hardware problem, with a digitizer. Is there any way to be sure, or is it best to take it to a repair shop?


Both my father and mother have blue eyes, just like me. But my sister has dark brown eyes, contrary to what I've read about the dominance of brown eye genes and recessive blue eye genes. What happened (apart from the possibility that my mother dated a brown eyed guy from which she was born, which for sure didn't happen because we both look like our father and mother; though you never know with those Italians...) that gave her those dark eyes?

In high school we studied the inheritance of eye color, as it was explained to us in the most simple way: blue eye color is a recessive, monogenic, autosomal trait. Now I know that it is a bit more complicated than that; there are several genes which determine the inheritance of eye color. That's as far as I my knowledge goes.   Which are these genes and what do they encode for? How is the eye color trait inherited? Provided that a man with blue eyes and a woman with brown eyes have a child, can the probability of their child to have blue eyes be calculated?


Is SO Help Center built from scratch (ASP.NET) or  is it based on some tool ?

What tools and technologies are used to build the Stack Exchange Network?  See also:


I'm installing  on Ubuntu 14.04 and when I type sudo npm install -g slap its giving me the error sudo: npm: command not found .  the node version on my system is 0.10.33 and the npm version is 1.4.28  I didn't find any solution to this problem, can anyone help me ?  Thank You in advance.

What is the difference between installing node.js with 'sudo apt-get install nodejs' or downloading the Linux Binaries (.tar.gz) and following  instructions?  Is the outcome the same?


I am wondering if it is correct to say, "I love it that the children enjoy school", or "I love that the children enjoy school", in colloquial speech?

I want to express the following: You are blaming me for your lack of concern and I like that (in a sarcastic way).  Which one of the following sentences would be correct?        I like it that your lack of concern is my fault.   I like that your lack of concern is my fault.


Is there any way to automatically restart the AutoIncrement () function based on the Field Value on ArcMap?   I am developing a model in  ModelBuilder to name parcels automatically. The polygons are already sorted on the order they should be. I need to execute the AutoIncrement function on each of the Field Values separately. To simplify the problem, the result I need is shown below. I already have the !Name! field and based on that, the !Count! field result must be acquired automatically.

I am needing to auto increment a field based on groups within a feature class. I have 8 plots within a given polygon and I need to assign them an ID from 1-8 for each set of plots within each polygon. The polygon would have its own unique ID number to be used to group the plots.  I assume it would be an alteration of this:  rec=0 def autoIncrement():  global rec  pStart = 1   pInterval = 1   if (rec == 0):    rec = pStart   else:    rec = rec + pInterval   return rec


Let $f : G \to H$ be a group isomorphism. Show that for any integer $k$ and for any $g \in G$, the sets $A = \{a \in G : a^k = g\}$ and $B = \{b \in H : b^k = f(g)\}$ have the same number of elements.  I've been trying this problem for quite a while but to no avail. I don't understand what the saying.

If $f: G \to H$ is an isomorphism of groups then show that for any integer $k$ and $g \in G$, these sets $A = \{a \in G : a^k = g$} and $B = \{b \in H : b^k = f(g)\}$ have the same number of elements.


Is there a defined difference between words like "egotistic" and egotistical" or "manic" and "maniacal" in that one could have a manic smile or maniacal laughter and other words that have similar forms?

I just came across a course name: Geometric and Theoretical Optics. The mismatched endings bug me. Why do we have both -ical and -ic endings?   Is there any difference in meaning between, say, theoretic and theoretical? I know that acoustic and acoustical mean slightly different things, but is this difference inherent in the words, or is it just usage — we happen to use the former for sound, and the latter for ceilings?


Suppose I build a FNN model. The last layer is a classification layer with softmax activation. A cross-entropy loss is used to classify a problems, such as logistic regression.  How would I calculate the cross entropy loss ?  But I can not fully understand the cross-entropy loss Please any convenient explanation  Thanks in advance

Suppose I build a neural network for classification. The last layer is a dense layer with Softmax activation. I have five different classes to classify. Suppose for a single training example, the true label is [1 0 0 0 0] while the predictions be [0.1 0.5 0.1 0.1 0.2]. How would I calculate the cross entropy loss for this example?


I am using a simulator to play craps and I am trying to return two values from the same method (or rather I would like to).  When I wrote my return statement I simply tried putting "&" which compiled and runs properly; but I have no way of accessing the second returned value.  public static int crapsGame(){   int myPoint;   int gameStatus = rollagain;   int d1,d2;   int rolls=1;    d1 = rollDice();   d2 = rollDice();   switch ( d1+d2 ) {     case 7:      case 11:       gameStatus = win;       break;     case 2:      case 3:      case 12:       gameStatus = loss;       break;     default:       myPoint = d1+d2;       do {         d1=rollDice();         d2=rollDice();         rolls++;         if ( d1+d2 == myPoint )           gameStatus = win;         else if ( d1+d2 == 7 )           gameStatus = loss;        } while (gameStatus == rollagain);   } // end of switch   return gameStatus & rolls; }   When I return the value as:  gameStatus=crapsGame();   It appropriately sets the varaible to win or lose but if I try something as simple as following that statement with:  rolls=crapsGame();   It is assigned the same value as gamestatus...a 0 or a 1 (win or lose). Any way that I can access the second returned value? Or is there a completely different way to go about it?

I want to return two objects from a Java method and was wondering what could be a good way of doing so?  The possible ways I can think of are: return a HashMap (since the two Objects are related) or return an ArrayList of Object objects.  To be more precise, the two objects I want to return are (a) List of objects and (b) comma separated names of the same.  I want to return these two Objects from one method because I dont want to iterate through the list of objects to get the comma separated names (which I can do in the same loop in this method).  Somehow, returning a HashMap does not look a very elegant way of doing so.


How do I prove this graph is nonplanar? It has 11 vertices and 25 edges, with a girth of 3.

Can anyone show me why this graph is nonplanar (which Mathematica assures me to be the case) ?    The graph passes the simple test $e \leq 3v - 6$.  I have tried and failed to find subgraphs isomorphic to subdivisions of $K_{3,3}$ or $K_5$.  The subgraph arising from deleting the right-most vertex and its adjacent edges is also nonplanar. In that subgraph, since only 3 vertices have degree 4, I suppose we cannot find a subdivision of $K_5$, so there must be a subdivision of $K_{3,3}$, but I cannot see it.


Is there a quick way to prime factorize 50!.  I wrote down all the numbers and then factorized, but that takes way too long.

How does one find the highest power of a prime $p$ that divides $N!$ and other related products?  Related question: How many zeros are there at the end of $N!$?    This is being done to reduce abstract duplicates. See   and  for more details.


Let $X$ be a random variable.I want to prove:  $E[x]=\int_{-\infty}^{\infty}{P[X > x]dx}$...(*)  Here is my proof.let $f$ be the PDF(probability density function) of $X$.$\int_{-\infty}^{\infty}{P[X > x]dx}=\int_{-\infty}^{\infty}{(1-\int_{-\infty}^{x}{f(t)dt)}dx}$.For the right hand size,we integral by part.  $\int_{-\infty}^{\infty}{(1-\int_{-\infty}^{x}{f(t)dt)}dx}=(x-x\int_{-\infty}^{x}{f(t)dt})\mid_{-\infty}^{\infty}+\int_{-\infty}^{\infty}xf(x)dx$.Since the first item $(x-x\int_{-\infty}^{x}{f(t)dt})\mid_{-\infty}^{\infty}$ equals zero,we have proved $E[x]=\int_{-\infty}^{\infty}{P[X > x]dx}$.  However I find my proof is $\textbf{WRONG}$ because PDF $f\quad\textbf{May Not be continous}$.How can I handle this case?Is (*) always right,or exists some counterexample?Well I am not good at probability theory,I search for help.

In , the tail sum formula for expectation is introduced for a nonnegative (0,1,...) discrete random variable $X$:  $$E(X) = \sum_{i=0}^\infty P(X > i).$$   I wonder if there is a similar formula for nonnegative continuous random variable $X$:  $$E(X) = \int_0^\infty P(X > x) dx?$$  If no, are there some conditions for it to hold? And how can it be proved?  Here is my thought:  If the cdf $F$ of $X$ is bijective, then $X=F^{-1}(U)$ for some random variable $U$ uniformly distributed over $[0,1)$. So $$E(X) =     \int_0^1 F^{-1}(u) du.$$  To prove the tail sum formula, it suffices to prove $$\int_0^1     F^{-1}(u) du = \int_0^\infty P(X > x) dx.$$ But I am stuck here.   What's more, is the condition that the cdf $F$ of $X$ is bijective really necessary for tail sum formula to hold? Can tail sum formula be generalized to a random variable that is not necessarily nonnegative?   Thanks!


I've already read this "  ". However, I still can't understand why does this work: switch(n){ case VAL:     int a;     ...     break; case OTHER_VAL:     a = 12     ...     break; }  suppose to this: switch(n){ case VAL:     int a = 12;     ...     break; case OTHER_VAL:     ...     break; }  I understand that that initialization part is bypassed, at the label val, so why does the declaration part isn't?.

I've always wondered this - why can't you declare variables after a case label in a switch statement?  In C++ you can declare variables pretty much anywhere (and declaring them close to first use is obviously a good thing) but the following still won't work:  switch (val)   {   case VAL:     // This won't work   int newVal = 42;     break; case ANOTHER_VAL:     ...   break; }     The above gives me the following error (MSC):     initialization of 'newVal' is skipped by 'case' label   This seems to be a limitation in other languages too.  Why is this such a problem?


How can I check if my laptop is using NVIDIA or Intel graphics card so I know what drivers to download?   I notice this similar question   but that user seems to have both installed, and is asking which a program is using, and that question is closed too. My question is of a system with one installed, and asking which is installed.  Often times a laptop model doesn't indicate whether it has an Intel or an NVIDIA graphics card installed, and the drivers page lists both.  I have had that in the past with a laptop, and the last time I was advised by the manufacturer, samsung, to install both, and then whichever driver was the correct one would work.  But each one includes software, which I could I suppose experiment with uninstalling, but it doesn't seem ideal to me. This laptop happens to be an acer, but clearly this is a situation with various laptops from different manufacturers. So it's not peculiar to any one particular model, and model number won't help either with such laptops, in determining which make graphics card is installed.  I am wondering if there is a better way though. A way to check which graphics card is installed, intel or nvidia, so that I can then know which driver to install.

I have a laptop with nvidia graphic. How can I find if the program is running with nvidia graphics card or with the intel graphics.I searched for this query but could not find the suitable answer?


I have installed the LaTeX class files for Springer svjour3 as instructed at   But I cannot import template.tex into LyX (using plain latex option). The error comes out:      "cannot convert file- an error occured while running tex2lyx -f   template.tex template.lyx"   Next I tried to create a new file from template provided by LyX, svjour3.lyx. No problem here, I can view the PDF. Then I exported it to a .tex file (using plain LaTeX option) and tried importing it back again to LyX. The cannot convert error above appears.

i'm getting this error message  An error occurred while running: /Applications/LyX.app/Contents/MacOS/tex2lyx" -f "nrcd.tex" "nrcd.lyx  while importing tex file to lyx 2.0.6 can anyone help please?


I understand how integers and rationals are expressed/derived in ZFC. But what about the irrational numbers? Can they also be expressed? If not, are there other axiomatic set theories able to express them? As for Dedekind cuts, from my understanding (maybe wrong), any irrational in question must have a 1-1 explicit function to a natural number, in order for the method to work (As an example the square root of 2 has such a function).  It boils down to this: is there an isomorphism between the the set of irrationals (as "just" numbers) and a a set of pure sets?

In set theory, if natural numbers are represented by nested sets that include the empty set, how are the rest of the real numbers represented as sets?    Thanks for the answers. Several answers basically said for irrational numbers that  A Dedekind cut is a pair of sets of rational numbers $\{L, R\}$. The set of real numbers is defined to be the set of all Dedekind cuts, where a Dedekind cut is a pair of sets of rational numbers $\{L, R\}$ which have no elements in common, and where all the elements of $L$ are less than any element of $R$.  Each Dedekind cut is a real number. This is where I have a problem - surely that can’t be correct. The set $L$ is a set of all rationals, and there must be a rational in the set $L$ that is greater than all other rationals in that set, even if we have no method of determining it. And similarly, there must be a rational in the set $R$ that is less than all other rationals in that set, even if we have no method of determining it. If every irrational number has a corresponding set $L$, then each irrational number has some such corresponding largest element of that set $L$, and then each irrational number has some corresponding rational number. And that would mean that the irrational numbers are countable. So, with Dedekind cuts,  the only conclusion is that there must be irrational numbers $x$ which are either greater or lesser than some irrational cut $y$ of the rationals, and between $x$ and $y$ there is no rational number.  But that is impossible, so that the Dedekind cuts cannot be the correct representation of the real numbers.  Surely the problem with Dedekind cuts is in using sets of rationals that include all rationals up to a certain rational. But there is an alternative method of representing irrationals can be defined in terms of infinite sets of rational numbers. For example, in binary notation, the non-integer part of $\pi$ is $.00100100\ 00111111\ 01101010\ 10001$. You define a set by: if the nth digit is a $1$, then  the natural number $n$ is in the set. And then we have that, for the real numbers between $0$ and $1$, that the set of real numbers is simply the set of all subsets of natural numbers. Each subset corresponds to some real number between $0$ and $1$.  And in this way, all real numbers can be considered to be some set based only on nested sets of the empty set.  But I still haven’t got a satisfactory answer for how negative numbers can be represented in terms only of sets containing the empty set. Any ideas?


We can say about a mention is scientific if we can analyze and repeat that mentioned process.  Our theory of the origin of the world is the big bang theory, which say that there was the absolutely nothing, and sometime occured something which explode this nothing (simplify summery). We are not able to analyze this process, and we have never can explode the absolutely nothing.  I see that we are living in an expanding universe and the opposite of this expansion means that one starting point is needed. But it is just a theory not an scientific mention (even so every scientist talk about this theory like a fact).   So simplify I would you like to ask that what evidences attest to the big bang theory is more than a simply theory?

Ok so the universe is in constant expansion, that has been proven, right? And that means that it was smaller in the past.. But what's the smallest size we can be sure the universe has ever had?  I just want to know what's the oldest thing we are sure about.


I have a Galaxy Note II and it's too slow due to low memory, I bought a 16 GB memory card and it still is slow, what to do?

Everything was working fine for a long time. But suddenly the device is getting slower than usual (e.g. apps react slowly when starting an action -- like the RSS reader takes "ages" to open an article). Also, several apps start crashing: force-closes as well as unexpected restarts. Sometimes this even involves some automatic reboot of the device.  Is there anything I can do, besides doing a factory-reset? Preferably it should work on un-rooted devices.  Remark: not all described problems may occur together, so on one device e.g. there might be no automatic reboot involved. Question remains the same, nonetheless.


I am using  and have the following working fine  <button type="submit" name="submit" value="complete" class="btn green"> Complete Section</button> <button type="submit" name="submit" value="save" class="btn green"> Save</button>   and  var form1 = $('#form_sample_1'); var error1 = $('.alert-danger', form1); var success1 = $('.alert-success', form1);  form1.validate({   errorElement: 'span', //default input error message container   errorClass: 'help-block help-block-error', // default input error message class   focusInvalid: false, // do not focus the last invalid input   ignore: "",  // validate all fields including form hidden input   invalidHandler: function (event, validator) { //display error alert on form submit                                   success1.hide();                     error1.show();                     Metronic.scrollTo(error1, -200);                 },     highlight: function (element) { // hightlight error inputs    $(element)    .closest('.form-group').addClass('has-error'); // set error class to the control group                 },                  unhighlight: function (element) { // revert the change done by hightlight                     $(element)                         .closest('.form-group').removeClass('has-error'); // set error class to the control group                 },                  success: function (label) {                     label                         .closest('.form-group').removeClass('has-error'); // set success class to the control group                 },                  submitHandler: function (form) {                     form.submit();                 }             });   However, what I would ideally like is if the "SAVE" button is pressed, for the form to be submitted and not validated i.e. only validated when the "COMPLETE" button is pressed.

I have a form with multiple fields that I'm validating (some with methods added for custom validation) with Jörn Zaeffere's excellent jQuery Validation plugin. How do you circumvent validation with specified submit controls (in other words, fire validation with some submit inputs, but do not fire validation with others)? This would be similar to ValidationGroups with standard ASP.NET validator controls.  My situation:  It's with ASP.NET WebForms, but you can ignore that if you wish. However, I am using the validation more as a "recommendation": in other words, when the form is submitted, validation fires but instead of a "required" message displaying, a "recommendation" shows that says something along the line of "you missed the following fields.... do you wish to proceed anyways?" At that point in the error container there's another submit button now visible that can be pressed which would ignore the validation and submit anyways. How to circumvent the forms .validate() for this button control and still post?  The Buy and Sell a House sample at  allows for this in order to hit the previous links, but it does so through creating custom methods and adding it to the validator. I would prefer to not have to create custom methods duplicating functionality already in the validation plugin.  The following is a shortened version of the immediately applicable script that I've got right now:  var container = $("#<%= Form.ClientID %> div.validationSuggestion");  $('#<%= Form.ClientID %>').validate({               errorContainer: container,     errorLabelContainer: $("ul",container),     rules: {         <%= YesNo.UniqueID %>: { required: true },         <%= ShortText.UniqueID %>: { required: true } // etc.      },     messages: {         <%= YesNo.UniqueID %>: 'A message.',         <%= ShortText.UniqueID %>: 'Another message.' // etc.     },     highlight: function(element, errorClass) {         $(element).addClass(errorClass);         $(element.form).find("label[for=" + element.id + "]").addClass(errorClass);         $(element.form).find("label[for=" + element.id + "]").removeClass("valid");     },     unhighlight: function(element, errorClass) {         $(element).removeClass(errorClass);         $(element.form).find("label[for=" + element.id + "]").removeClass(errorClass);         $(element.form).find("label[for=" + element.id + "]").addClass("valid");     },     wrapper: 'li' });


I can't see videos in Chromium in Ubuntu 16.04. How can I fix that?  http://www.quizover.com/oer/course/adaptive-submodularity-a-new-approach-to-by-daniel-videolectures     jalal@klein:~$ dpkg-query -s adobe-flashplugin dpkg-query: package 'adobe-flashplugin' is not installed and no information is available Use dpkg --info (= dpkg-deb --info) to examine archive files, and dpkg --contents (= dpkg-deb --contents) to list their contents. jalal@klein:~$ sudo apt-get install  adobe-flashplugin [sudo] password for jalal:  Reading package lists... Done Building dependency tree        Reading state information... Done Package adobe-flashplugin is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'adobe-flashplugin' has no installation candidate   I installed this: sudo apt-get install browser-plugin-freshplayer-pepperflash YouTube videos play with no sound. Please suggest fixes.  UPDATE: I added these, updated and installed flash but I can't hear video voices still:  $ sudo vi /etc/apt/sources.list       48 deb http://archive.canonical.com/ubuntu xenial partner      49 deb-src http://archive.canonical.com/ubuntu xenial partner  $ sudo apt-get update $ sudo apt-get install adobe-flashplugin

I have had significant problems with watching flash video in 64-bit Ubuntu.  Does anyone know of a good way to get flash running on the platform?