Every time I try to connect my Linux server via SSH, it asks me for my password. I’m using Ubuntu server 18.04 How do I do something to get the system to remember the password or just be in line of an Bash script to connect to the server server? example of what happens to me: ssh root@$ip root@xxx.xxx.xxx.xxx's password:   I did everything to don’t ask me again for password, but I failed. I’m already using a Bash script like this: echo PASSWORD ssh root@xxx.xxx.xxx.xxx  Then I copy and paste password into password field. But this doesn’t work.

I have created alias for username and it works fine   alias yb="ssh name@hostname"   It works fine, but I also want to create alias for password, Can anyone help how can I do this?


I have to show no proper intermediate fields exist between $Z_2$ and its overfield $GF(2^3)$, Can any one help?

We know that if a finite field $F$ has characteristic $p$ (prime), then $F$ has cardinality $p^r$ where $r = [F:\mathbb{F}_p]$.   I'm now trying to say something about the possible cardinalities of subfields of $F$. I can see that there is a subfield of cardinality $p^s$ for each $s$ that divides $r$, given by the fixed field of the group generated by $\phi^s$, where $\phi$ is the Frobenius automorphism.  Now suppose $K$ is a subfield of $F$. Then (since both are additive groups), Lagrange gives us that $|K|$ divides $|F|$, so $|K| = p^t$ for some $1 \leq t \leq r $ (alternatively, $K$ contains $\mathbb{F}_p$ and so is a vector space over $\mathbb{F}_p$ and is thus isomorphic to $\mathbb{F}_p^t$, where $t = [K:\mathbb{F}_p]$). By considering the multiplicative group of units of $K$ and $F$ respectively, we get that $ p^t - 1$ divides $p^r -1$. I want to make the leap to $t|r$, but I'm failing to see why this needs to be true. Any help would be appreciated.


I found a way to stop video tearing and stuttering where I need to make a file and paste it to /etc/x11/xorg.conf.d but it keeps saying “access denied”. How can I gain access and paste a file in that folder? Thank you in advance.

I am new to Ubuntu so please forgive my inexperience.  I am running Ubuntu Desktop 16.04.1 and I am set up as an administrator, I am the only user so I believe therefore I should be a root user.  However, when I try to copy a file from the root /var/www/html and paste it in /var/www/ directory, using any file management software (i.e. File manager, Files, Dolphin, etc.), I get the error message: Access denied. Could not write to.  Why can I not write to these directories?    Could this be because I have the automatic login option turned on?


Does the water need to boil or just be hot? Do I need to put salt and vinegar in the water or just salt? And if it needs vinegar, what kind? How long do I leave it in the water to get the white solid but not the yolk? I do not like raw egg white, so this is very important for me. But the tricky part is to have the yolk nice and runny though...

What's the best method to poach an egg without it turning into an eggy soupy mess?


I’ve been wondering why “past times” is wrong and only “times past” is correct and grammatical. When we refer to some events which occurred in the past, we can say “past events.” But why can’t we say “past times,” when we want to say the times which already passed?

I would expect the term "inspector general" to be "general inspector" instead.    In part, that may be because I know the German variant as "Generalinspekteur" of "Generalinspektor".  But I'm pretty sure it would be like this without knowing the German word, just from general language intuition.  So, why does the order of words make sense?    It would be interesting how it came to be like that - but that would not answer it alone. (An answer to  indicates it may be a method distinguish titles from general desrciptions.)


Lets start by saying that i am new at Ubuntu i think i have had it installed for about three weeks now.  So if my terminology is off please feel free to correct me as i would like to learn.   I installed this app called Screen cloud i was looking for an app that could take shots of sections of my screen like so    This was the first app i found.  I used the Ubuntu software install app on the left hand side bar     All good   Question  When i reboot in the morning how do i get it so that the app shows up in the top bar     So that i dont have to open the app in     And hit launch   i tried settings for the app i tried right clicking this top bar   I'm not sure how to add something to start up on Linux type system.

I had a nice GUI for changing startup applications (after logging in) on GNOME 2. How can I start that application on GNOME 3?   Where can I download it? What is the package name? What command is used to launch it? I have Pidgin still launching on start, but I have converted back to Empathy, so I would like to know how I can remove Pidgin and start Empathy instead.


I was a Windows 10 user, and got tired of it, and decided to install Linux. I tried Linux Mint, but I had some problems.  So I created an Ubuntu USB boot drive, and tried to install Ubuntu that way.   I changed the BIOS to use the USB to load, and it got into the Ubuntu installation menu I selected the language, and after that i choose to "try Ubuntu without installing", but the Ubuntu logo appeared, and it froze right after that. I tried it several times, and mounted the USB several times as well, but nothing worked so far.   Any suggestions?

I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:


What could be the reason for the following stack trace :     java.lang.NullPointerException: storage == null --------- Stack   trace --------- java.util.Arrays$ArrayList.(Arrays.java:38)   java.util.Arrays.asList(Arrays.java:155)   mypackage.MyJava$5.onClick(MyJava.java:479)   android.view.View.performClick(View.java:5205)   android.view.View$PerformClick.run(View.java:21164)   android.os.Handler.handleCallback(Handler.java:743)   android.os.Handler.dispatchMessage(Handler.java:95)   android.os.Looper.loop(Looper.java:171)   android.app.ActivityThread.main(ActivityThread.java:5417)   java.lang.reflect.Method.invoke(Native Method)   com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)   com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)   ------------------------------- --------- Cause --------- -------------------------------   I tried assigning null to the items but this issue cannot be reproduced. Only few times this get reproduced i cant understand please help me..My code as follows  final String[] items= Global.currencycodes; AlertDialog.Builder builder = new AlertDialog.Builder(mContext);                 builder.setTitle("Currency");                 builder.setSingleChoiceItems(items, Arrays.asList(items).indexOf(((TextView) container.findViewById(R.id.currency)).getText()), new DialogInterface.OnClickListener() {                     public void onClick(DialogInterface dialog, int item) { } builder.create.show();   Here this exception from the line      builder.setSingleChoiceItems(items,   Arrays.asList(items).indexOf(((TextView)   container.findViewById(R.id.currency)).getText()), new   DialogInterface.OnClickListener() {   Thanks in Advance.

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


After I login in Ubuntu 16.04, it redirects to the above screen and then again back to the login screen. The last commands I ran were sudo apt-get install python3 and sudo apt-get install ubuntu-desktop

My Ubuntu is stuck in a login loop when trying to enter my desktop. When I login, the screen gets black and soon after that the login screen comes back.   I've read that the problem might be caused by an error depending on the graphics, here's my graphics card: ATI Radeon 7670M


I have the stackoverflow app installed on my Galaxy Tab 3. Every time I open a question, no matter from which stack site, I receive a layout error, which makes the app unusable.

I can reproduce that every time now, I go to a site, open an article, then to the next site, open another article. The Feed page pops up for a second, the article page lays over this with some some transparent areas (see picture). The same app-version is ok on a Smartphone with Android 4.4.2. I also sent in some bug reports.    Edit  1.0.71 isn't the solution yet. I go to Meta SE, then to an article. When I want back to Meta SE again, it crashes. Much earlier than before. I already sent in a bug report for this.  Another Edit  I can describe it better now. From the questions-page of a site I go to a post. When I use the back button, everything is ok, I can go to the next site. When I try to go to the next site directly from the post, it crashes. This only happens on the Nexus 10 with Android 5.1.1, App version 1.0.71. Hope this helps.  Edit3  This is fixed in 1.0.73 now. Thanks again.


Given $A_1 = \{\emptyset\}$ and $A_{n+1} = A_n \cup (A_n \times A_n)$ define $A = \bigcup_{i=1}^\infty A_n$, what is $A\times A$?  I'm kind of lost on this one, any help would be appreciated!

A question from my homework I'm having trouble understanding. We are given:  $A(1) = \{\varnothing\}$, $A(n+1) = A(n)\cup (A(n)\times A(n))$  $A=A(1)\cup A(2)\cup A(3)\cup \cdots \cup A(n)\cup A(n+1) \cup \cdots$ to infinity  The questions are:  1) show that $A\times A \subseteq A$  2) Is $A \times A = A$?  Thank you for your help.  I've tried writing $A(2)$ but it gets really complicated and I'm having trouble understanding what the sets are. Let alone solve the question.


For the past few days I've had to restart my PC a couple times a day because I'm running out of memory. I have 32gb DDR3 1866mhz ram.  Here is a screenshot of the nonpaged driver memory usage snapshot with poolmon sorted by bytes.  Does anything look abnormal?

A few days ago I updated my PC to Windows 10. However, after some use my PC started to slow down until it was impossible to use – it was due to high memory usage. After a restart, everything came back to normal (total usage around 25% of 8GB of RAM). However, during a few hours of usage the memory builds up again to 70%, and if not restarted it further goes to 100%, and later on even freezes. Task manager does not help very much as it does not show all the processes (added screenshots below). Also tried RAMMap but it gives an error: "error refreshing database". I tried Googling this question, yet without much success.  I do not know much about PCs, but maybe some of you know this issue, or could help to find out what is using my RAM.


Let $\{a_{k}\}_{k\geq 1}$ be any sequence of real numbers, must there exist a smooth function $f:]-\epsilon,\epsilon[\rightarrow \mathbb{R}$ (for some positive $\epsilon$) such that for every positive integer $k\geq 1$, we have $f^{(k)}(0)=a_k ?$  Thank you a lot.

Do you have some reference to a proof of the so-called Borel theorem, i.e. every power series is the Taylor series of some $C^{\infty}$ function?


I'm trying to make an ajax call which contains the following example parameter  farms.company_id=1   but when received by PHP it has been changed to   farms_company_id=1   What's the best way to prevent this?

If I pass PHP variables with . in their names via $_GET PHP auto-replaces them with _ characters. For example:  <?php echo "url is ".$_SERVER['REQUEST_URI']."<p>"; echo "x.y is ".$_GET['x.y'].".<p>"; echo "x_y is ".$_GET['x_y'].".<p>";   ... outputs the following:  url is /SpShipTool/php/testGetUrl.php?x.y=a.b x.y is . x_y is a.b.   ... my question is this: is there any way I can get this to stop? Cannot for the life of me figure out what I've done to deserve this  PHP version I'm running with is 5.2.4-2ubuntu5.3.


Question: Given two Banach spaces $X$ and $Y$, if there exists an onto linear isometry $T:X\to Y$ and $X$ is a Hilbert space, is it true that $Y$ is a Hilbert space?  Intuitively this seems true to me. To prove this, one just need to construct an $\langle\cdot, \cdot \rangle$ on $Y\times Y$ and show that it is an inner product.

As written in the title, does there exists a $\mathbb C$-Banach space isometric to a Hilbert Space but whose norm is not induced by an inner product?  Since an inner product in the Hilbert space has to fulfill the Parallelogram Identity, how could it be that such a $\mathbb C$-Banach space exists?


I want to know how to simulate gas that doesn't look like pure smoke. Like the gas one might see coming out the side of a pipe or on a really hot day in the desert. I don't know how to explain it: gas without the smoke.

I know how to do a heat distortion effect in compositing.   What I am looking for is a way to do the same effect with a material set up in cycles.   What would be the best way to create a procedural material that can be placed in front of any object and make it look like heat is rising in front of it (without compositing)?  Any ideas would be greatly appreciated.


Can I travel to Ireland on a UK Standard Visitor visa on Indian passport for the purpose of attending a conference?

I have a Indian passport and a UK ICT Tier 2 Visa valid through April 2016. Do I need a separate visa to visit Dublin in March?


Tell me what is your opinion on this matter.   Tell me what your opinion on this matter is.   Which one is correct? I understand the word order in the sentence like I want to know where she is. But does my above sentence belong to the same type like I can recognize who is happy? I am not sure.

I believe the sentence in the title is grammatically correct.   Recently I've seen too many people writing it this way:     I'm not sure what is the right way.   Is it grammatically correct as well? Maybe in a different sense? Or simply misuse by non-native speakers?


I saw a usb to firewire cable () and I was wondering if I can hookup my USB 3.0 flash disk to firewire port on PC. What drivers would be involved? Any benchmarking info much appreciated.   Thanks.

I am in the process of buying a new laptop for video capture / editing, and it's proving difficult to find one at a decent price / spec that includes Expresscard for Firewire connectivity (which I really need).  It does seem like Expresscard is on the way out based on what I've seen recently.  Since the assumption seems to be that USB 3.0 is the heir apparent to Expresscard I was wondering what people's thoughts were on whether it should be possible to convert a Firewire input to USB 3.0.  There don't seem to be any devices around at the moment that do this but is this because USB 3.0 is still in its infancy or because it's not practical / possible?


How do I prove $\gcd(a, b) = \gcd(a+b, b)$.  I know that by the euclidean algorithm, I can obtain the following equations  $ax_1 + by_1 = \gcd(a, b)\tag{1}$  $(a+b)(x_2) + (b)(y_2) = \gcd(a+b, b)\tag{2}$  I tried some algebraic manipulation but I can't seem too prove that $\gcd(a, b) = \gcd(a+b, b)$.

I know that $\gcd(a,b)$ divides $a$ and $b$, and must also then divide $(a)(t)$ ($t$ being some integer).  This makes sense to me, but how do I prove it?  It seems that the addition of $(a)(t)$ is a continuation of the linear combination of $\gcd(a,b) = av + bu$ for some $v$, $u$ being elements of $\mathbb{Z}$.    Any help?


As a child I watched a couple of episodes of a sci-fi series set on a planet, that was far from resembling Earth - I remember a dark, stoney scenery and tanks of some form. It was probably in English, and it was a 3D animated series.  The only thing I really remember is a character that was burning, it was basically a walking fire with black eyes and flames instead of hair, the entire being just burned and it was orange/yellow- a fire. And then there were some sort of aliens or alien-like creatures, a father and a son, or a father and a daughter. in some way they resembeled bugs. The ''fireman'', and those two aliens were the ''good guys'' of the series, but I can't remember what they fought against or ran away of...

I remember seeing this series back when I was in the early grades of primary school (prep to 3) so this would be between 1996 and 1999  from what I remember it was set in space and the cast was made up from people from these different worlds, one of the characters is from a fire attributed world and I get the impression he was small framed (I think).  at one point in the series this entity appears called the Beast Planet appears, the one scene I do remember is that this Beast Planet attacks the fire planet, the front of the beast planet opens up with this claw and grabs the fire planet from bellow and then the fire planet is slammed into the beast planet dooming the fire planet but I think the beast planet was unharmed.  I also seem to remember that the cast discover the other planets have engines which allows the remaining planets to escape from the Beast Planet rather than them being sitting ducks.  I remember that this beast planet, despite being called a beast is actually more machine. I began remembering this series after playing Galaxy Angel where I saw the  and it reminds me of this beast planet


What is the closed-form expression to the following problem

This may be a simple question, but I was slightly confused.  I was looking at the second line $S_n(x)=1-x^{n+1}/(1-x)$.  I was confused how they derived this.  I know the infinite sum of a geometric series is $1/(1-x)$.  I just can't figure out how the partial sums, $S_n(x)$, have $1-x^{n+1}$ on the numerator.  How was this derived?  Thank you.     Example 5.20.   The geometric series   $$     \sum_{n=0}^\infty x^n   = 1 + x + x^2 + x^3 + \dotsb $$   has partial sums   $$     S_n(x)   = \sum_{k=0}^n x^k   = \frac{1 - x^{n+1}}{1 - x} \cdotp $$   Thus, $S_n(x) \to 1/(1-x)$ as $n \to \infty$ if $|x| < 1$ and diverges if $|x| \geq 1$, meaning that   $$     \sum_{n=0}^\infty x^n   = \frac{1}{1-x}   \qquad   \text{pointwise on $(-1,1)$}. $$   (Original image .)


So, I was thinking simply fog cloud.. to obscure vision then fireball.  Input?

The 'blind' status defines     A blinded creature can’t see and automatically fails any ability check that requires sight.   Many spells and effects require targets to perform a dexterity saving throw. For example, the 'Fireball' spell requires that     each creature in a 20-foot-radius sphere centered on that point must make a dexterity saving throw.   Do blind creatures automatically fail this saving throw? If not, then, which saving throws are based on sight? Do the rules specifically mention this?


the variable s is not increasing already tried several forms, pass by parameter, global variable, nothing is right  public static int p(int m,int p,int t,int s ){    int resultado;          if(m == 0 ){       s++;       resultado =  s;              }     else if(m == 1){       s++;       resultado =  t;    }          else {       s++;       resultado =  2*p(m-1,p,t,s) + p(m-2,p,t,s);    }          return s ;       }

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?


The following behavior occurs in OS X (10.9.5) with the BSD utils, but not Linux (Ubuntu 15.10) with the GNU utils.  OS X:   $ man -v  man, version 1.6c   Linux:   $ man --version  man 2.7.4   I'm trying to write a shell script to automatically parse the supported options for a given program for use in bash/tcsh autocompletion. For instance here's the name and synopsis section output by name perl when viewed in the terminal.  $ man perl | cat  NAME        perl - The Perl 5 language interpreter  SYNOPSIS        perl [ -sTtuUWX ]      [ -hv ] [ -V[:configvar] ]             [ -cw ] [ -d[t][:debugger] ] [ -D[number/list] ]             [ -pna ] [ -Fpattern ] [ -l[octal] ] [ -0[octal/hexadecimal] ]             [ -Idir ] [ -m[-]module ] [ -M[-]'module...' ] [ -f ]             [ -C [number/list] ]      [ -S ]      [ -x[dir] ]             [ -i[extension] ]             [ [-e|-E] 'command' ] [ -- ] [ programfile ] [ argument ]...  $ man perl > /tmp/perl.out   I first got suspicious when  $ </tmp/perl.out awk '/SYNOPSIS/ {print}'   didn't print any lines, then I opened the file in vi and saw this. Why the heck are there so many unnecessary duplicated characters and ^H characters.  N^HNA^HAM^HME^HE        perl - The Perl 5 language interpreter  S^HSY^HYN^HNO^HOP^HPS^HSI^HIS^HS        p^Hpe^Her^Hrl^Hl [ -^H-s^HsT^HTt^Htu^HuU^HUW^HWX^HX ]      [ -^H-h^Hhv^Hv ] [ -^H-V^HV[:_^Hc_^Ho_^Hn_^Hf_^Hi_^Hg_^Hv_^Ha_^Hr] ]             [ -^H-c^Hcw^Hw ] [ -^H-d^Hd[t^Ht][:_^Hd_^He_^Hb_^Hu_^Hg_^Hg_^He_^Hr] ] [ -^H-D^HD[_^Hn_^Hu_^Hm_^Hb_^He_^Hr_^H/_^Hl_^Hi_^Hs_^Ht] ]

After downloading the source code for Bash, I was browsing through the doc directory and came across the following files:    is a regular  file used to build the man page.  is like a plain text version of the man page – only that it has the  liberally distributed throughout it.   These control characters are not displayed in the representation provided by the Git web interface but the  and examined in text editor such as Vim.  Running the file command on bash.0 prints the following output:  bash.0: ASCII text, with overstriking   I’ve never come across this file format before and I was wondering what its purpose is and how it’s used. Searching the Web for the phrase “ASCII text, with overstriking” hasn’t been very enlightening.


When I check one of our site's rankings when signed in, I get lower rankings for my own site than the rankings I would get while signed out.  If anything, it should have been the other way round?  Any possible reasons?  Thanks  (Not duplicate, please take a minute to understand the question rather than rushing to a quick judgement)

I have noticed when I am logged into my Google account and type my domain into Google search the results differ from than when I'm not logged in. For example when I'm logged in my site is 1st and when I'm logged out... it's 5th...  Why do search results differ when logged in?


My husband always corrects me when I say "I'm done... (with whatever it is I'm doing.)" He says that proper grammar requires you to say "I have finished." As Saying "I'm done" refers only to the "done-ness' of food.  Help me!

Which of these alternatives is grammatically correct?     I’m done.      or        I have finished   Like I’m done sounds very American, but is it grammatically correct?


I don't think this question has been asked yet, and if it has I apologize. I am currently running two websites on an Apache2 server which are both are on port 80. On Google Domains I have the DNS for the domain of each site pointing to the public IP address of the server, so if I'm outside of local network I can navigate to  or  and it will show the appropriate website. If I'm locally on the network I can't just visit  or  because that's point to my public ip. So normally when I want to visit a site locally I'd just navigate to the private ip of the server and it'd show the website, but if that ip has two websites running how do I differentiate between the two? Am I needing to set up a local DNS, and if so how would I go about doing that? I'm running Ubuntu 20.04, and thanks ahead of time!

I have an Ubuntu machine that I'm using as my home Internet router.  It uses a USB mobile broadband modem as its Internet connection, and shares this with another router (via the router's "Internet" port) which I use as my LAN.  How do I redirect requests from within my LAN for a given URL to a custom IP address (ex have google.com redirect to x.x.x.x)?


Imagine a very large black hole, with a mass equal to a large number of galaxies.  Assume a space station is in orbit around the black hole some distance from the event horizon at a point A.  An astronaut in a ship, let's call him observer B, launches from the station toward the black hole.  I have been told (correct me if I'm wrong) that from observer B's point of view, he wouldn’t feel any effects from approaching the event horizon—at least as far as he could determine from inside his spaceship.  In fact, the visible event horizon, from his own point of view, would continually move away from him so that he could never actually reach it.  Is this correct?  If he were to watch the space station out his window, he would see it orbiting faster and faster.  He would see the space stations occupants racing around.  Eventually he would see many generations on the space station be born, live and die.  As he approached the event horizon (as seen by him or the original Schwarzschild radius as seen by A?), he would see stars born and die and eventually galaxies form move out and disappear.  He would see the entire life of the universe in an instant as he got ever closer to the black hole.  Is this correct?  Mathematically, the observer on the space station could calculate these relativistic effects.  In fact, observer A would calculate that on the other side of the event horizon, the space and time axes would actually be swapped relative to his own point of view.  Of course, he cannot see beyond the event horizon, so this would be a strictly mathematical exercise.    Now this is based on my reading of several books on general relativity.  If any of it is wrong, please tell me.  Otherwise, I’m assuming I’ve interpreted things correctly.  My thoughts turn to the following thought experiment.  Now, I do this thought experiment.  I imagine many stars and galaxies moving around inside the event horizon of this black hole (remember it is very large).  And I consider a layer S a fixed distance from the singularity, but located inside the event horizon as observed from some point, say our original station at A.  Let’s assume a person is located at a point P on the surface S.  Nothing between P and the singularity could be seen by this observer P.  Any light between the singularity and P would move inward towards the black hole, so the observer at P would see nothing but blackness if he peered in the direction of the singularity. True?   What I want to know is if observer P peered outward, toward the universe, what would he see?  I’ve been told due to gravitational lensing he would see all the light entering the event horizon concentrated somehow.  I also want to know what the stars and galaxies located inside the event horizon but outside the shell S would look like to the observer at P.  Is it possible that as he looked outward, he would be looking into the past?  Is it possible that he would see all of space limited to his little shell S, and points further out than P would be points in his past?  Is it possible that at the event horizon, he would see his entire shell contract to a point, as if it came from a big bang in his past?  And is it possible that the spacetime he is unable to perceive, between P and the singularity, appears to be in his future?  From his own point of view, he can’t perceive it, because nothing can reach him from that future (from closer to the singularity) without travelling faster than light.  I don’t know if any of this is correct.  Just something I’ve been thinking about and it could be totally out to lunch.

This question was prompted by . Notoriously, if you calculate the Schwarzschild coordinate time for anything, matter or light, to reach the event horizon the result is infinite. This implies that the universe ages by an infinite time before someone falling into the black hole reaches the event horizon, so could that person see the universe age by an infinite time?  To be more precise, suppose the observer starts falling from rest at time $t = 0$ and some initial distance $r > r_s$. If we wait for some time $T$ then shine a light ray at the falling observer. Will the light ray always reach the falling observer before they cross the event horizon? If not, what is the formula for the longest time $T$ that we can wait and still be sure the ray will catch the observer? If $T$ is not bounded it implies that observer could indeed see the end of the universe.  I can think of a qualitative argument for an upper limit on $T$, but I'm not sure how sound my argument is. The proper time for the observer to fall to the event horizon is finite - call this $\tau$. The proper time for the light ray to reach the horizon is zero, therefore the light ray will reach the observer before they cross the event horizon only if $T < \tau$. Hence $T$ is bounded and the observer won't see the end of the universe.  I think a more rigorous approach would be to determine the equations of motion (in the Schwarzschild coordinates) for the falling observer and the light ray, and then find the condition for the light to reach the falling observer at some distance $\epsilon$ from the event horizon. Then take the limit as $\epsilon \rightarrow 0$. In principle this seems straightforward, but in practice the algebra rapidly defeated me. Even for a light ray the radial distance:time equation isn't closed form (Wolfram claims it needs the $W$ function) and for the falling observer the calculation is even harder.


I have two e-bike batteries. One of which i am using to power my ESP32. Now i want to switch to other battery when my batt-1 is low. I am switching battery using relay. But doing so, I suspecting i might reset esp32 and hence state will be lost. I need solution around this problem.  P.S. Can not give external power supply to esp32

I have an application with two AA/AAA batteries (so total of 3V or less) powering a unit with a micro controller. I want to design a low cost switch over circuit that can disconnect the battery supply when an external supply is connected with 3.3V. I also want to be able to detect with a micro controller when the external cable is connected supplying 3.3V.  I am aware that this can be done with some source selector switch OR controller ICs like LTC4413. But these chips are relatively very expensive and the minimum input volt is only about 2.5V. I would need to go down as much as about 1.8V, as battery can go down to that level. Looking for some ideas how this can be done, thank you.


Replicators were shut down to save energy on the Voyager. However, with fusion technology which is available to all starships, energy shoud be dirt cheap. Why is the fusion power generated on the Voyager not enough to keep the replicators in operation? In comparison, there were no problems with the other starships. Picard, Kirk, and Sisko never had to shut down their replicators to save power. Furthermore, if  replicators had to be shut down to save power, it contradicts the post-scarcity economy that Star Trek boasts about.

Replicators have been cited as the invention that allowed humans to stop working for a living. This implies that replicators are cheap and even free because they produce food at super-low cost. So low that humans can stop work. However, if replicators are indeed so low-cost, why were they shut down in the Voyager? Cooking replaced replicators in the Voyager. This implies that replicators are more expensive than manual cooking. If so, how can replicators give humans the luxury to stop working?


I live in the quintessential "middle of nowhere", and as such it is nearly impossible for me to get a weekly, monthly, or even yearly group together.  I have tried to get a semi-regular group of friends to play once a month, and it ended up not working out because we could get about half an hour of serious play due to time constraints caused by school.    I've also tried a virtual tabletop session composed of the same friends, but it ended up being bogged down due to everyone's lacking internet speeds and/or tremendous ping times.    I have come to realize that a group of friends just won't work, so I am now looking to get into a D&D Encounters type of group. There is a town within about half an hour from me, but due to my age (14 years), I don't think I would be accepted by any FLGS groups.  Is there a way I could get into a schedule that fits mine (meaning maximum 1 session a week) with people around my age, or at least a group that is comfortable with each other's ages?  I would prefer a newer edition, ideally 4e or 5e, and either of these would work because not all content is released for 5e yet. It's not even close to a deal breaker though, because all editions have the same core goal, which is, of course, entertainment.  Note that I am aware of similar questions (e.g. ) that address the general issue of find gaming groups to play in. However, I feel that the answers to these do not sufficiently address the issue of my age and the problems that would cause in gaining access to groups.

I'd really like to learn how to play pen-and-paper RPGs.  I know that it takes a few players to actually sit down and play, but I'm not at all sure where to find more gamers.  How do I find existing groups to join? Or, are there any resources online that may help me find existing RPG groups or players?


How do I compute $\sum_{k = 1}^{\infty} \frac{1}{k^2-\frac{1}{16}}$ ?  Mathematica says the sum converges and it somewhat looks like the Basel problem, but so far I do not know how to approach it.

So I have been trying for a few days to figure out the sum of   $$ S = \sum_{k=1}^\infty \frac{1}{k^2 - a^2} $$ where $a \in (0,1)$. So far from my nummerical analysis and CAS that this sum equals  $$ S = \frac{1}{2a} \left[ \frac{1}{a} \, - \, \pi \cot(a\pi) \right] $$  But I have not been able to prove this yet. Anyone know how? My guess is that the  sum of this series is related to fourier-series but nothing particalr comes to mind.   For the easy values, I have been able to use telescopic series, and a bit of algebraic magic, but for the general case I am stumpled. Anyone have any ideas or hints? Cheers.


I watched this as a teen, so it is probably dated before 1995. If I remember correctly, one of the initial scenes was set on a space-ship and there were some heavy vault-like doors. I believe some kind of accident causes at least one of the sealed doors to open and an alien breaks free. Somehow, the alien (if my memory serves me right it was just referred to as a "Xenomorph" later) gets to Earth and thats where most part of the movie happened. Most likely it was "present" Earth, no future setting.

In 1991 or 1992 I saw a two-part (probably made for) TV US movie. It is about an alien starship crash landing on planet Earth (in the USA). An attractive 100% human-looking woman (I believe the only survivor) interacts with our male lead so that they can solve a problem at hand (like communicating with other aliens, or recovering the ship, or working against an alien threat, something like that). She is telepathic and lost her spouse in the space ship wreck (or maybe she just can't ever get back to him because of the broken-down ship?). I remember her flashbacks where she is intimate with her spouse by the touching of hands.  During their time together on earth they fall in love and I believe she stays in the end.  I know this is not much but there aren't that many two-part sci-fi TV movies so someone may remember?


$$\int_{ - \pi /2}^{\pi /2} \frac1{2007^{x} + 1}\cdot \frac {\sin^{2008}x}{\sin^{2008}x + \cos^{2008}x} \, dx .$$  This integral stuns me for a while, I just can't solve it! I tried integration by recurrence since here it seems that we have something that looks like a recurrence, but nothing comes up. I also tried all the integration techniques I'm aware of but they just don't work.  So I fear like this integral uses something like Fourier, or some Laplace transform thing or something of that sort but I don't know them.  That's why I will be very thankful if they could explain me how to solve it.  Thank you.

I am trying to solve this integral $$ \int_{-\pi/2}^{\pi/2} \frac{1}{2007^x+1}\cdot \frac{\sin^{2008}x}{\sin^{2008}x+\cos^{2008}x}dx $$ A closed form does exist despite the looks of the integrand.  This problem is from some old high school IMO training courses.  I am not sure how to solve it. The only information that may be of help is $$ \sin x=\sum_{n=1}^\infty \frac{(-1)^n x^{2n+1}}{(2n+1)!}, \quad \cos x=\sum_{n=1}^\infty \frac{ x^{2n}}{(2n)!} \quad \forall \ x $$ Thanks, I am looking for a complete solution, not a description as of what to do.


How can I get rid of notification icons for Skype in particular, but any app in general when the app was killed using one of the many available task managers, but the notification icon still remains on the notification bar (that is the part that is persistent at the top of the screen in Jellybean)?  Device: Nexus 7 (2013), Android 4.3

I'd like to figure out how to hide the icons of the status bar that would appear in the left. Is there a way to control that? Some apps such as Weather.com don't have the option to hide that icon from the status bar.


yes I have a very important question. Does the English language have and academy like the Royal Spanish Academy? Anyone who answers is so very kind.Word-choice?

Some languages have a "regulatory body" issuing recommendations and guidelines regarding the use of that language.  For example in the case of Spanish it's the  whose status is recognised in all Spanish-speaking countries. The Academy, among other things, publishes a dictionary (""), in print and , which is usually given a lot of prestige (but is not without , of course).  Are there any such authorative—or at least influential—institution(s) or publication(s) for the English language?


Here's from an old song (1963) "" by Lesley Gore.       She don't know that she's a lucky girl   Here's another example, "Silence is Golden" (1964) by The Tremeloes [YouTube ]      Oh, don't it hurt deep inside to see someone do something to her.   I wonder how common it is to say "She don't" or "don't it". Do native English speakers often use these?  By the way, Lesley Gore is American, and the Tremeloes is British.

Recently I was exposed to a lot of uses of "She don't + infinitive" ( + don't), instead of "she doesn't + infinitive" ( + doesn't). I'm not sure if it is a mistake or just accepted usage sometimes.   I found it in a very famous songs such as:   "" by Bon Jovi   Also in  (in 3:04)     But she don't know you like I know you Slim, no one does   She don't know what it was like for people like us growin' up, you gotta call me man   I'll be the biggest fan you'll ever lose   Sincerely yours, Stan, P.S. we should be together too   You can find a lot more by searching in you tube "he don't" or "she don't".


Compute, for every real value $x$, the double limit:   $$\lim_{n \to \infty} \lim_{m \to \infty} \cos^m(n!2\pi x)$$  How do i go about solving the above problem? Note that this is a problem from a real analysis course, not calculus.  Thanks for looking at my question.

I stumbled upon this "relation" (is the name correct?):  $$ \lim_{m \to \infty} \lim_{n \to \infty} \cos^{2n}(m! \pi x) = \begin{cases} 1,&x\text{ is rational}\\ 0,&x\text{ is irrational}\end{cases} $$  How is it called and why is it so? I'm really not asking for a proof since I fear it would be too complicated for me to understand, but rather for an "intuition".


I want to achieve following things  Example  array[1,2,3,4,5,6,7,8,9,10,11,12]   and an integer i. Every time I want to get an i-length sub-array from this array. If i=3  Expected/Required Output :  get a sub-array [1,2,3] in first time, in second time I get[4,5,6]. Is there anyway to do that efficiently.

I have a list of arbitrary length, and I need to split it up into equal size chunks and operate on it. There are some obvious ways to do this, like keeping a counter and two lists, and when the second list fills up, add it to the first list and empty the second list for the next round of data, but this is potentially extremely expensive.  I was wondering if anyone had a good solution to this for lists of any length, e.g. using generators.  I was looking for something useful in itertools but I couldn't find anything obviously useful. Might've missed it, though.  Related question:


I have a list of files to put through a for loop. They are named  FA2_00032.png, FA2_00033.png, etc   I have variables $imID which contains FA2 string, $startFrame which contains the start frame (e.g. 00034) and $endFrame which contains to end frame (e.g. 00894).  I have managed to get the list of relevant files using:  eval echo ${imageID}_{${startFrame}..${endFrame}}.png;   This outputs      FA2_00034 FA2_00035 FA2_00036 etc   But now I need to pass this to the for loop. That is,  for file in *the above list*   where *the above list* is the block quoted list above. $file should contain FA2_00034, FA2_00035, etc for use in the for loop.

How do I iterate over a range of numbers in Bash when the range is given by a variable?  I know I can do this (called "sequence expression" in the Bash ):   for i in {1..5}; do echo $i; done   Which gives:     1    2    3    4    5   Yet, how can I replace either of the range endpoints with a variable? This doesn't work:  END=5 for i in {1..$END}; do echo $i; done   Which prints:     {1..5}


How to control in Blender 2.8 how tight a mesh will be to a vertex. I thought it was vertex weight but after several tries no success. As you can see in the example image, the mesh follow the vertex ponted with green arrows in a loose fashion while those marked with red arrows fully "atract" the mesh.

How can I use the subdivision surface modifier to create more high poly meshes without ruining sharp edges? For example this mesh  The sphere should be subdivided but the rim of the cylinder should stay the same because it is a sharp edge. This is the result of the subdevision  How can I get sharp edges to not be affected by the sub surf mod?


In our household circuit we have ac supply of 50 Hz. It means current reverse its direction in every 100th second. I think then, current flows in one direction then another.Then, why do we have live and neutral wires in our household circuit?

In domestic electrical circuits, there are 3 wires - live, earth and neutral. What is the difference between the live and neutral wires?  As there is AC supply, it means that there are no fixed positive and negative terminals. Current rapidly switches direction. Does that not mean that both the live and neutral wires carry the same amount of current, alternatively? Why is the neutral wire called 'neutral'?


Prove that for infinite set $A\setminus B$ and countable set $B$ it is true that  $A\setminus B$ and $A$ are equinumerous.  Have tried to apply fact that every infinite set contains countable one, however don't understand what to do with elements enumeration needed for bijection.. P.S First came up with this problem here: , however referenced solution seems to be for different task..

This seems evident, but I cannot come up with a reasonable proof for:  Question: show that if $X$ is an infinite set and $Y$ is a countable set, then $|X \cup Y|=|X|$


Given an N x N square grid what is the minimum number of overlapping squares you need to draw such that every line of the grid is covered by the side of a square.  The question can be rephrased as follows (which is how I arrived at the question):  A child wants to draw a NxN square grid in Paint by only drawing squares. Because he is lazy, he wants to draw as few squares as possible. Find the minimum number of squares he needs to draw.  N=1 : 1 You obviously only need one square.    N=2 : 3  One 1x1 square in the top left corner, one in the bottom right and a 2x2 square.    N=3 : 4    N=4 : 6?    N=5 : 8?    I hope you've understood what I mean by now. Is there any formula or algorithm for the general case? I thought about making a quick brute force algorithm but I realised how slow it would be and although it wouldn't be too complicated to write it's pretty tedious. It needs to do around $$\sum_{0 \le x \le n+1, 0 \le y \le n+1} 2^{min(n+1-x,n+1-y)}$$ operations. So before I try to write a brute force algorithm I thought I would ask this here in case anyone comes up with the solution or a more efficient algorithm.

How can we draw $14$ squares to obtain an $8\times8$ table divided into $64$ unit squares?  Notes:  -The squares to be drawn can be of any size.  -There will be no drawings outside the table.


I see this in some code , and I have a hunch it is not a good practice. What are your opinions ?  @RestController public class AddController {     @RequestMapping(value="/Add", method = RequestMethod.POST)      public ActionResponse add(@Valid @RequestBody    AddRequest request) {         // Method does as much as necessary     }     static class AddCRequest {                       public String parameter1;         public long parameter2;         public long parameter3;     } } }   Having the static nested class as a parameter of of the methdos of the service , is it good ? Static implies only one instance of the class ? How will it behave with concurrency ? A very good theorical-technical explanation would be appreciated.

What is the main difference between an inner class and a static nested class in Java? Does design / implementation play a role in choosing one of these?


I just convinced one artist to install Ubuntu, invited to the open source sphere. He agreed to come along. And I advised him to install Ubuntu along with his Windows installation.   I mistakenly deleted his C drive and converted to ext4. That made two partitions one is free space and other is the ext4 partition. I need to recover his documents, his artworks, videos, and other files on C drive using Ubuntu liveboot. I tried with testdisk.   Any other options or suggestions.

I have a Toshiba satellite A-200 laptop with a Vista OS on it with 4 NTFS partitions  (C:) Vista  (D:) Entertainment  (E:) Work  (F:) Sources   and I wanted to start using Ubuntu instead. So I tried it first from the live CD and everything was OK and all the partitions were shown and working and so I decided to install Ubuntu to replace Vista on the (C:) drive. After I did that I can no longer find my folders and files on the (D:), (E:), (F:) partitions and the only file system that is shown is one 198 GB although my HDD is 320 GB.  I can't access the lost data on the remaining 120 GB which I hope is still there and not totally lost  I am now working from the live CD but I am unable to install testdisk. Can I recover the Vista partitions by the product recovery CD to get my laptop back to the factory settings? Can I recover the NTFS partitions using a recovery program for Windows or will that make the problem worse?   I need these data badly as I don't have a backup for them.


I've run the following commands as root:  apt-get update apt-get upgrade apt-get dist-upgrade   all work fine, but then i run  do-release-upgrade   and it says "no new release".  This makes no sense as I've upgraded a clone of this machine in the past and it went straight to 10.04.  I can get out to the internet fine.  Any ideas why this might be?

I'm using Ubuntu 11.04. The update manager once found the new release 'oneiric', and still shows up this screen when I log on use ssh:  Welcome to Ubuntu 11.04 (GNU/Linux 2.6.38-14-generic x86_64)   * Documentation:  https://help.ubuntu.com/  0 packages can be updated. 0 updates are security updates.  New release 'oneiric' available. Run 'do-release-upgrade' to upgrade to it.  Last login: Wed Apr 25 16:22:48 2012 from ***   But I didn't upgrade then, and change my apt sources. And now I cannot upgrade to 'oneiric'. do-relase-upgrade shows:  $ sudo do-release-upgrade Checking for a new ubuntu release No new release found $   And apt-get dist-upgrade shows:  $ sudo apt-get dist-upgrade Reading package lists... Done Building dependency tree Reading state information... Done Calculating upgrade... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. $   I can successfully update all my packages.    File contents of source.list:  $ cat /etc/apt/sources.list ## See sources.list(5) for more information, especialy # Remember that you can only use http, ftp or file URIs  deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty main universe restricted multiverse deb-src http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty main universe restricted multiverse deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-security universe main multiverse restricted deb-src http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-security universe main multiverse restricted deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-updates universe main multiverse restricted deb-src http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-updates universe main multiverse restricted deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-backports universe main multiverse restricted deb-src http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ natty-backports universe main multiverse restricted   # deb http://ubuntu.dormforce.net/ubuntu/ lucid main universe restricted multiverse # deb-src http://ubuntu.dormforce.net/ubuntu/ lucid main universe restricted multiverse # deb http://ubuntu.dormforce.net/ubuntu/ lucid-security universe main multiverse restricted # deb-src http://ubuntu.dormforce.net/ubuntu/ lucid-security universe main multiverse restricted # deb http://ubuntu.dormforce.net/ubuntu/ lucid-updates universe main multiverse restricted # deb-src http://ubuntu.dormforce.net/ubuntu/ lucid-updates universe main multiverse restricted  # CDROMs are managed through the apt-cdrom tool. # deb http://archive.canonical.com lucid partner # deb http://archive.canonical.com lucid-security partner # deb http://archive.canonical.com lucid-updates partner # deb-src http://archive.canonical.com lucid partner # deb-src http://archive.canonical.com lucid-security partner # deb-src http://archive.canonical.com lucid-updates partner   #medibuntu repo # deb http://packages.medibuntu.org/ lucid free non-free # deb-src http://packages.medibuntu.org/ lucid free non-free  # deb http://extras.ubuntu.com/ubuntu maverick main #Third party developers repository deb http://mirrors.sohu.com/ubuntu/ natty main restricted multiverse universe deb-src http://mirrors.sohu.com/ubuntu/ natty main universe restricted multiverse #Added by software-properties deb http://security.ubuntu.com/ubuntu/ natty-security universe main multiverse restricted deb-src http://mirrors.sohu.com/ubuntu/ natty-security universe main multiverse restricted deb http://mirrors.sohu.com/ubuntu/ natty-updates universe main multiverse restricted deb-src http://mirrors.sohu.com/ubuntu/ natty-updates universe main multiverse restricted   File contents of /etc/update-manager/meta-release:  $ cat /etc/update-manager/meta-release # default location for the meta-release file  [METARELEASE] URI = http://changelogs.ubuntu.com/meta-release URI_LTS = http://changelogs.ubuntu.com/meta-release-lts URI_UNSTABLE_POSTFIX = -development URI_PROPOSED_POSTFIX = -proposed   What may be the problem of this?


I just created a 3D model of a barrel and UV unwarped. That thing below is the screenshot of the UV image editor.   Then I clicked new button below the UV image editors window and gave a name barrel and unchecked the alpha option, and selected blank to color fill option then clicked ok. then I changed the viewport to texture mode. I can't see the color grid texture on my object. Image below.   i am using blender 2.78n thanks in advance for any help.

I have added a texture to a cube in the UV editor and it shows up fine in textured view  But when I render it there is no texture  What have I done wrong?


What is the different between rigorous proof and proof based on intuition on this problem?  It seems to me that these triangle are equivalent in area.

Below is a visual proof (!) that $32.5 = 31.5$. How could that be?    (As noted in a comment and answer, this is known as .)


Recently, i bought a wifi adaptor,but as a result of new to ubuntu , i have no idea about how to  install drivers to run the wifi adaptor. Following some instructions from others, i used   lsusbto check out the chips id of the wifi adaptor.Here it is:ID 148f:7601,and i dont' know   what to do next,hope someone could help fix this problem.Thanks!

I am trying to install a Ralink wifi adapter in Ubuntu Desktop 14.04.  The system is not detecting the wifi.   lsusb lists the device as:  Bus 002 Device 004: ID 148f:7601 Ralink Technology, Corp.  I have the rt2800 USB driver listed in "/etc/modules"; Following some instructions on the web, I tried this command:  echo 148F 7601 | sudo tee /sys/bus/usb/drivers/rt2800usb/new_i  lsmod | grep rt2800 returns the following:  rt2800usb              26581  0  rt2x00usb              20041  1 rt2800usb rt2800lib              83150  1 rt2800usb rt2x00lib              48886  3 rt2x00usb,rt2800lib,rt2800usb mac80211              545990  3 rt2x00lib,rt2x00usb,rt2800lib crc_ccitt              12627  1 rt2800lib


I have two 1TB hard drives in my computer:  one for Windows 10 for my gaming one empty, which I want to install Linux on to use as my workstation.  I have no idea how to do the installation and all the tutorials I've seen only teach you how to set up a dual boot on one single hard drive by partitioning. I would really like to avoid partitioning my hard drive with the Windows OS on it and keep the two separate. Can someone enlighten me on how to do this please?

I'd like to see the full How-To on how to use manual partitioning during Ubuntu installation. The existing guides (at least those I found here) cover only automatic part and leave untouched the manual part (or extremely short and contain no pictures).  I'd like to cover such situations:     If your disk contains other systems:


I need a function that can test whether a string has any special characters in it. I'm currently using the following function with no luck:  import re  def no_special_characters(s, pat=re.compile('[@_!#$%^&*()<>?/\|}{~:]')):   if pat.match(s):     print(s + " has special characters")   else:     print(s + " has NO special characters")   I get the following results:  no_special_characters('$@')  # $@ has special characters no_special_characters('a$@') # a$@ has NO special characters no_special_characters('$@a') # $@a has special characters   This doesn't make any sense to me. How can I test for ANY special characters in a string?

What is the difference between the search() and match() functions in the ?  I've read the  (), but I never seem to remember it.  I keep having to look it up and re-learn it.  I'm hoping that someone will answer it clearly with examples so that (perhaps) it will stick in my head.  Or at least I'll have a better place to return with my question and it will take less time to re-learn it.


I want to show that for a function $f \in C_c^2((a,b))$ non-negative, the inequality  $$\sup \left(\frac{|f'(x)|^2}{f(x)} \right) \le 2 \sup |f''(x)|$$ holds.   I noticed that the left term is equal to  $2 |\sqrt{f(x)}'|^2.$ So the question is equivalent to: Can I bound this term just by the second derivative? Currently, I don't see how this could work.  The problem I am also having with the exercise is that we get problems if $f(x)=0$ cause then we may divide zero by zero on the left-hand side and it is not immediate to me that the limit is finite.   If anything is unclear, please let me know.

Let $f:\mathbb{R} \to \mathbb{R}$ be a twice differentiable function. And let  $$\eqalign{   & M_0  = \sup \left|f(x)\right|  \cr                & M_1  = \sup \left|\frac{d}{dx} f(x) \right|  \cr                & M_2  = \sup \left|\frac{d^2}{dx^2} f(x) \right| \cr }$$ Prove that  $$M_1 ^2  \leqslant 4M_0 M_2$$ I can not think how I can relate these values in some inequality )=


This  was last seen 19 minutes ago, yet he asked  13 minutes ago.

I posted what I think is a clever answer to:    But then I noticed the question was posted a while ago on Mar 2.  I wanted to see what the chance of the user logging back in and seeing my answer, but the  says the user was seen on Feb 19.  I thought this was supposed to be the date they last logged in? How could they have asked a question on Mar 2 if they haven't logged in since February?  Thanks


Some background & context  When including third party logos, we often get given low quality files. Mostly these are low resolution JPGs, but I have seen badly hand drawn scans (expected to be used as is) or even photos of old stationary.  Recently we were given a folder with all the variations of a logo in a number of formats and sizes. Great! But. There are a lot of variation, some of which have only very slight differences, a lot of file types, a lot of sizes and no usage guidelines. So it's not always obvious which to use. I don't have the files to hand to count but there was probably at least 40 different files.  Another example: I worked on a project for a company who wanted a main logo with a variation for each department, then for each of these a horizontal version with the full company name, website and tagline, a square version with just the logo and website and just the logo.. Then for all of these a PDF, an EPS, a low res JPG, a high res JPG, a low res transparent PNG and a high res transparent PNG. All the variations were sufficiently different and they did (in their opinion) have justification for wanting all the different file types so this isn't as bad as the first example, but I did think this was too much.    My question - How many variations is too many? (or too few)  Note: By variations, I mean all the final files you deliver, so all actual design variation (e.g. horizontal / vertical / square variations, 4 color & monochrome variations, size variations etc) as well as all file types (e.g. EPS, JPG, PDF) and sizes (e.g. low and high res JPGs)  I always at a minimum supply vector and bitmap versions of the logo in full color and monochrome. Assuming no specific requests, is this enough? Should low-res versions be supplied, or is relying on the client to downsample the high-res version ok?  Size variations are also needed (sometimes?), for example, simplifying complicated shapes for showing the logo at smaller sizes. Should this always be done, or only when absolutely needed?  I understand this depends on a lot of factors and varies for each project, but should I try to keep the number of files to the minimum essentials or supply as much (as is appropriate and within reason as I can?    Edit: This question -  - is about initial ideas and concepts, I am asking specifically about finished work and the final delivered files.  This question -  - is very similar, but more general. I believe the reasoning behind the question is different.

What files should i put in a logo pack to give to clients? Should I put small, medium and large version of my logo as well as the vector file.


Call a cardinal $\kappa$ worldly iff $V_\kappa\vDash ZFC$. Let $\kappa_\alpha$ be the $\alpha$th worldly cardinal, i.e. the least worldly cardinal such that $\{\beta\lt\kappa_\alpha|\beta\text{ is worldly}\}$ has order-type $\alpha$. Since the class of worldly cardinals are closed, then $\kappa_\omega=\sup\kappa_n$. Therefore, $V_{\kappa_\omega}\vDash\forall\alpha(\exists\delta\gt\alpha(V_\delta\vDash ZFC))$. Now define $f: \omega\rightarrow\kappa$ by $f(n)=\kappa_n$. We have that $f(n)$ is definable and absoloute to $V_{\kappa_\omega}$. Therefore, $f"\omega\in V_{\kappa_\omega}$ by the axiom of replacement. But this is impossible.


I made a server on Minecraft Forum (because it was easier) and it said:     To finish claiming this server, set this token token removed somewhere in your server's MoTD. Once the server is verified, you can remove the token.   How do I change the MoTD?MOTD  Minecraft Forum Does Make Servers Not Only Listing

All I want to do is post my Minecraft server on the main Minecraft Servers website but I don't really know what to do with the code they gave me. Please help?


I've tried to solve the following problem (1.1.30 from Berkeley Problems in Mathematics, no solution is provided therein), but I'm not sure if my solution is correct. I wanted to ask you for your opinion.   The problem: Let $S$ be the set of all real $C^1$ functions $f$ on $[0,1]$ such that $f(0)=0$ and $$ (*)\int_0^1f'(x)^2\mathrm{d}x\leq 1  $$ Define $$ J(f) = \int_0^1 f(x)\mathrm{d}x. $$ Prove that the function $J$ is bounded on $S$ and compute its supremum. Is there a function $f_0\in S$ at which $J$ attains its supremum? If so, give $f_0$.  My attempts: First note that for any $y\in[0,1]$, $\int_0^1 f'(x)^2\mathrm{d}x \geq \int_0^y f'(x)^2\mathrm{d}x$. Thus, using the Cauchy Schwartz inequality,  $$1\geq \int_0^y f'(x)^2\mathrm{d}x \cdot\underbrace{\int_0^1 1^2\mathrm{d}x}_{\geq\int_0^y 1^2\mathrm{d}x}\geq \left(\int_0^y f'(x)\cdot 1\mathrm{d}x\right)^2=(f(y)-f(0))^2=f(y)^2 $$ which implies that $|f(y)|\leq 1$. Therefore, $J(f)\leq|J(f)|\leq1$ so we have shown boundedness.  The rest is still a bit shaky:\ Now the supremum of $J$ on $S$ is attained when the equality in $(*)$ holds (why is that? I'm not sure I could show this). This is the case for $f_0(x)=x$. Now $J(f_0)=\frac{1}{2}$. My guess is that therefore $J(f)\leq \frac{1}{2}$ is the supremum and maximum.  Thank you for your suggestions.

This question is related to Daniel Fischer's answer . Suppose $f$ is a real $C^{1}$ function on $[0, 1]$ such that $f(0) = 0$ and $\int_{0}^{1}f'(x)^{2}\, dx \leq 1$. Then (essentially by Cauchy-Schwarz), we have $\left|\int_{0}^{1}f(x)\, dx\right| \leq 2/3$ as Daniel Fischer stated in his answer.  My question is: Is there an example of a function such that we have equality in $\left|\int_{0}^{1}f(x)\, dx\right| \leq 2/3$? I was thinking of maybe a smoothed version of a function which takes the value $0$ on $[0, 1/2)$ and $4/3$ on $(1/2, 1]$ but that seems complicated to construct, moreover, the derivative in some neighbourhood of $1/2$ might be hard to control.


My problem is simple. I want to have my static resources served at /static/* context, but my specific servlet serving /* context. Since /static/* is a subset of /* it does not work. My web.xml looks like this:  <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">  <display-name>template-guice-jersey-tomcat</display-name>  <session-config>      <session-timeout>30</session-timeout>  </session-config>  <welcome-file-list>      <welcome-file>index.jsp</welcome-file>  </welcome-file-list>   <!-- set up Google Guice Servlet integration -->  <filter>     <filter-name>guiceFilter</filter-name>     <filter-class>com.google.inject.servlet.GuiceFilter</filter-class>  </filter>  <filter-mapping>     <filter-name>guiceFilter</filter-name>     <url-pattern>/*</url-pattern>  </filter-mapping>   <servlet-mapping>                                                                                <servlet-name>default</servlet-name>                                                                                <url-pattern>/static/*</url-pattern>                                                                                </servlet-mapping>                                                                                <listener>                                                                                <listener-class>de.danbim.templateguicejerseytomcat.GuiceServletConfig</listener-class>                                                       </listener>                                                                                </web-app>

I deploy a webapp on two different containers (Tomcat and Jetty), but their default servlets for serving the static content have a different way of handling the URL structure I want to use ().  I am therefore looking to include a small servlet in the webapp to serve its own static content (images, CSS, etc.). The servlet should have the following properties:   No external dependencies Simple and reliable Support for  header (i.e. custom  method) (Optional) support for gzip encoding, etags,...   Is such a servlet available somewhere? The closest I can find is  from the servlet book.  Update: The URL structure I want to use - in case you are wondering - is simply:      <servlet-mapping>             <servlet-name>main</servlet-name>             <url-pattern>/*</url-pattern>     </servlet-mapping>     <servlet-mapping>             <servlet-name>default</servlet-name>             <url-pattern>/static/*</url-pattern>     </servlet-mapping>   So all requests should be passed to the main servlet, unless they are for the static path. The problem is that Tomcat's default servlet does not take the ServletPath into account (so it looks for the static files in the main folder), while Jetty does (so it looks in the static folder).


I am 49 years old, Psychologist with MA in Psych, PhD in Public Health and postdoc at University of Toronto. However,all my academic background here stated is from Brazil and I have been facing some stumbling blocks to enter Academia in Canada. Therefore, I decided to apply for a Masters in Counselling. Would my age and an already extensive academic past with a long research history [non North American] hurt my application? lastly, would I face institutionalized racism due to my non-anglo surname and academic history? My GPA's are: BA= 8.1 ; MA= 9,1 ; PhD= B. Thank you!

I am 33. I live in the US. I am a neither a US citizen, nor a green card holder. I have worked in various jobs as a research assistant (physics, biology, economics) usually involving programming, mathematics or statistics.  As a newly minted undergraduate, I didn't really have much confidence in myself and I completely ruled out graduate school as pointless.  I didn't think of myself as smart enough.  I drifted into working in labs, because those are some of the easiest ones for which one can get a work permit in the US as a non-American.  Having worked in academia for a while now, I've had a chance to leap into various fields and help build solutions to complex problems.  I think I have literally gone as far as I can go researching in academia with no higher degree.  I work at one of the top universities in the world.  (If you looked at US News rankings or the Academic Ranking of World Universities, it's in the top 5.)  Lately, I've been thinking about applying for graduate school.  I do have a few papers in various fields.  I'm thinking of a PhD in either pure mathematics, applied mathematics, statistics or computer science.   I see two big minuses to applying to graduate school:   Most people applying are more than a decade younger than I am.  (Alas, more than a few gray hairs have made an appearance in recent years.) Perhaps my achievements would look good for someone younger, but partially my achievements are the result of a long career rather than any special brilliance. So, I wonder how my record will be perceived.  I did take GRE and I scored 800 quantitative, 800 verbal and a 5 on the essay.  (I would most likely have to do a GRE subject test depending on what field I ultimately decided.)   Please advise on how accomplished, but older candidates, are viewed in the graduate school application process.


A little bit of context, i've ripped some models from the game Yugioh duelist of the roses and was a able to open them in 3ds max to edit some of the stuff. after doing that I save the kind of deformed models as .obj and try to open them in blender but every time I try nothing shows up. its showing I have something in the outliner but no object appears! If anybody can point me in the right direction for how to fix this id greatly appreciate it!

I try to import .obj files from this project:  - the files contain Polygon Mesh Data.  When I import the obj file into blender, the outliner shows a new mesh added, but nothing is visible in the 3D viewport:      Any help will be appreciated.


I want to define in LaTeX some words. For instance I have this long words: ''contemporaneamente''. So I can define \def\cont{contemporaneamente}. The problem is that it is not treated as normal text and so there is a problem in spacing.   If I write ''\cont bla bla'' the result is: ''contemporaneamentebla bla''. So I have to write ''\cont\ bla bla'' to obtain what I want.   I know also that in order to obtain what I want I can define \def\cont{contemporaneamente }. The problem in doing this is that when I want to put the word at the end of a sencence and I have to write ''\cont.'' the result is ''contemporaneamente .''

I have a definition:  \newcommand{\arnold}{Arnold Schwarzenegger}   When I refer to it by:  \arnold is a   it is rendered as:   Arnold Schwarzeneggeris a    In order to have a space in front of "is" I would need to write  \arnold\ is a   Is there some other shorter way?


I know that $H\cong K$ may not imply $G/H\cong G/K$ as a counter-example take $G=\Bbb{Z}$, $H=2\Bbb{Z}$ and $K=3\Bbb{Z}$, $G/H=\Bbb{Z}_2\ncong\Bbb{Z}_3=G/K$. But I cannot get whether $G/H\cong G/K$ implies $H\cong K$. Can anybody help me in this regard? Thanks for the assistance in advance.

I know that given a group $G$ and two normal subgroups $H,K \subset G$ then it is not true that:  "if $H \cong K$ then $ \frac{G}{H} \cong \frac{G}{K} $ (the counterexample is quite easy with products of cyclic groups) "  My question is: Is the converse true?   i.e.     Given that $\frac{G}{H} \cong \frac{G}{K}$ then $H \cong K$ ?   I feel that the answer is no, but I can't think of an example.


In a , I asked about the possibility to create a custom "cited as" which related to the author names and a label when disambiguation is needed.  In some of the cases, I got the right citation in the bibliography, however there is an extra space between the label and the final ")." This creates a break, were the Author-Label is on one line and the ")." is on the next line.  By trial and errors, I've identified that this is due to the "\usebibmacro{cite}%", which is redefined in my custom CBX file. This would be something as:   Author First, Title and potential subtitle 3ed, Location year (cited as Author-Label ).   I'd prefer something similar to:  Author First, Title and potential subtitle 3ed, Location year (cited as  Author-Label).   However, I don't see where the parenthesis is set and especially were it is ended. My guess is that it may be in the "labelname" part, but I'm kind of stuck to this point.  What should I surgically edit in which biblatex macro?  NB: a MWE is difficult to reproduce, at the moment, I circumvented the issue by adding and extra space in the title.  .bbx  \ProvidesFile{biblatex-xawi.bbx}[2018/04/18 v1.1]     \RequireCitationStyle{authortitle}  \newbibmacro{citedas:cite}{%   \begingroup     \delimcontext{cite}%     \DeclareFieldFormat{bibhyperref}{##1}%     \csuse{blx@hook@cite}%     \csuse{blx@hook@citekey}%     \undef\cbx@lasthash     \undef\cbx@lastyear     \citetrackerfalse\pagetrackerfalse\backtrackerfalse     \defcounter{maxnames}{\blx@maxcitenames}%     \usebibmacro{cite}%   \endgroup }  \newbibmacro{citedas}{%   \ifsingletitle     {}{         \printtext[parens] {%             \bibstring{citedas}%             \addcolon\space             \usebibmacro{citedas:cite}         }     } }   .cbx  \renewbibmacro*{cite}{%   \iffieldundef{shorthand}     {\ifnameundef{labelname}        {\usebibmacro{cite:title}}        {\ifsingletitle           {\printtext[bibhyperref]{\printnames{labelname}}}           {\printnames{labelname}%        \setunit{\nametitledelim}%        \usebibmacro{cite:title}}}}%     {\usebibmacro{cite:shorthand}}}

I see that the code in many packages and examples contains percent signs % at the end of (many) lines. What are they used for? Do they affect the parsing of those lines?


I recently had some beef with other users on Stack Overflow. And why I'm getting the feeling that giving context is not a desired thing on Stack Overflow, I'm hopeful it might be here, so I'll give a little bit of context before coming to my actual question. Basically, I was facing a programming problem (streaming audio data from a mobile device), and I couldn't figure out what what the standard solution for this problem was, so I was asking what the standard solution for this is. The question was closed for being too broad, which I still find odd. I would have understood if the question had been closed for being off-topic for Stack Overflow, citing 4. of the listing on the Stack Overflow Help page listing off-topic types of questions, being:   Questions asking us to recommend or find a book, tool, software library, tutorial or other off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.   While I don't think that is exactly the same as asking for what is the standard way, I can understand that it is possible to consider my question as asking for a recommendation. But I don't want to argue about that distinction as well. Nor do I want to talk about how badly this was handled by some users (deleting helpful comments from another user and myself without giving a reason why, for instance). It might be worth another topic here how to avoid such behaviour, but never mind now. In the end, I was so angry that I deleted the question. (*) What I want to ask is the following:  If I'm having a software development issue I cannot easily solve by myself, it is usually that I want to do something and would like to know if there's a standard solution for this. Usually some API or library, or even protocol, which is commonly used for tasks like this. Of course, I'm googling things then, but it happens that I can't find the answer, or that all answers I can find are wildly outdated, citing solutions that no longer exist.  In my opinion, these are legitimate questions about software development. Now, while it's debatable if they fall under the clause stated above, let's assume for now they would be considered off-topic for Stack Overflow. What Stack Exchange site would such kind of questions be on topic? (*) Footnote: I think I found an answer to my original question by now (still doing some research on it). I think if someone suggested that, I would have accepted the answer and the answer would have not been a recommendation for a software library, which underlines my point that I'm not convinced my question actually was off-topic. This is not a duplicate of the question where to ask for software, since I am not. I‘m asking where to ask what technology to use. I don’t want software recommendations, but platform/protocol/general technology. Please note my comment below, I find these superficial duplicate suggestions very unwelcoming. To illustrate the difference: if I'm asking for a good way to distribute information on the internet, the answer could be to suggest using a web server. A software recommendation would be Apache, for instance. A software recommendation is something you want when you already know what technology to use. This is a step before that, choosing the right direction.

Bjarne Stroustrup once mentioned in one of his bigthink interviews that one of the greatest problems most programmers have is not finding or using the right libraries.  On stackoverflow and programmers, I've observed a trend towards questions like "I want to do this, is there a [library | programming language] for that", or "I have these {n} [library | language] candidates for my project; which one would yield me the least amount of headache given these requirements".   Since questions like these aren't exactly programming questions in the sense of "this code should do this, but it does this, why?", they are often (though not always) being closed as "not constructive" because they do not have a definite answer (which is true, and according to the FAQ they would be off-topic on both stackoverflow and programmers).  Nonetheless, I think library questions are valid, and that it is helpful for any programmer to receive independent input from experienced programmers (at least it helps me a lot every time I browse through one of those closed questions, which I found through google). Does anyone agree that posting library choice questions should be explicitly allowed on either stackoverflow or programmers?


This article  talks about dunes visible on comet 67P:     In August, the European Space Agency (ESA) achieved a major success   when its Rosetta probe rendezvoused with comet 67P. The spacecraft has   been returning spectacular images of this strange little world,   located midway between the orbits of Mars and Jupiter. Among its   latest photographs is the image below showing what appear to be dunes   like those found on the deserts and beaches of Earth.     The comet would acquire an extremely thin atmosphere when it is close to sun. But this atmosphere would have very low density and would not produce winds as on earth.  So how can there be sand and small rocks on 67P?

What mechanism is responsible for the creation of these dunes on Comet 67P/Churyumov-Gerasimenko?  The following high resolution picture from ESA's Rosetta mission shows the dunes:       At a distance of 7.8 km from the surface, the image scale is about   66.5 cm/pixel, so each 1024 x 1024 pixel frame is about 680 m across (although if we assume the furthest point away is an additional ~1 km   further from the centre, the image scale is about 92 cm/pixel).   So the scale of the dunes is on the order of tens of meters along the crest. And each crest are probably just a few meters apart.


I'm trying to understand the  and came across this paragraph that seems crazy to me:     when the rocket moves, its thrust acts through the distance it moves. Force multiplied by distance is the definition of mechanical energy or work. So the farther the rocket and payload move during the burn (i.e. the faster they move), the greater the kinetic energy imparted.   It makes sense to me that a force acting against an immovable object doesn't impart any change in kinetic energy- the fixed force of gravity can push the stones of Stonehenge into the ground for thousands of years, but if they don't move there's no energy changing hands.  What makes no sense at all to me is that the change in kinetic energy is directly proportional to the distance the object moves. What if the object just coincidentally happens to be moving anyway? Say you have two objects; one is at rest, and the other is coasting through space at 1000km per second. You impart a tiny little 1 newton force on both objects for a second or so. The first object moves a meter so you've increased its kinetic energy by one joule. But just because the second object happens to be traveling at hypervelocity already, you've imparted the kinetic energy of a stick of dynamite? How do those definitions of work and kinetic energy make sense?  Come to think of it, the Earth is moving around the Sun at 30 km/s so if I stand on one of the stones of Stonehenge around sunrise, is the weight of my body dumping 17 megawatts of energy into it? It seems that the definition of work contains some kind of caveat that the distance the object moves has to be related to the force somehow but that's completely unclear to me.  Also, how does the object moving through space at a constant velocity even "know" that it's moving? There is no universal inertial frame of reference that everything moves relative to; who's to say that the fast-moving object isn't at rest and we are the ones moving at 1000 kilometers per second?

From this  by orlp:     If I strap a rocket booster to a rocket in space and fire it for one second, then the work provided is much higher when the rocket is flying fast compared to when the rocket was stationary. In both cases the rocket fires for the same duration but in the former case the rocket travels a much greater distance during this period. What gives?


I'm running OTA-13 on a Nexus 4. I have a Y OTG cable. When I plug power into the Y and then the Y into the phone, it shows power. Then, when I plug a USB thumbdrive into the USB, it doesn't mount nor show any activity in the syslog. I've read elsewhere that this should work. Is the problem with my particular cable, or the micro-USB connector on the phone, or ? What should I try? Thanks.

I would like to connect a USB Mouse, Keyboard or Storage Device to my Nexus 4. So far I know, for this USB OTG must be supported. Unfortunately I can not find any actual information about this.  Does anybody know whether USB OTG is supported by Ubuntu-Touch? If yes, does anybody know if it would work with a Nexus 4 device?


The problem is the following, my canvas width and height is relative to its parents. In css, its width and height is set to 95%. That causes my getMousePosition function to not work properly, meaning that when I click on a canvas point, the actual point where say a rectangle is drawn is far from the observed clicked point.  Here is the html stuff

                 <canvas class = "Blackboard" id = "blackboard-canvas" >                  </canvas>

Color Options

Tool Bar

                         <canvas id='color-option-canvas' >                          </canvas>

                         Tool bar options goes here

     and the relavent css  .Blackboard{  border-style: ridge; border-color: gray; border-width: 5px;  width: 96%; height: 96%; cursor: crosshair; position: relative; -webkit-border-radius: 16px; -webkit-box-shadow: 0px 6px 7px #0a0505;   };   .Blackboard:active{ cursor: crosshair;   }   .Container{ border-color: #666; border-width: 10px; border-style: inset; background-color: gray; width: 700px; height: 400px;  }   #right-div, #left-div{ height: 100%;  }  #left-div{ float: left; width: 60%;  }  #right-div{ float: right; background-color: black; width: 40%;  }   Is there a way to 'normalize' it or or something?  EDIT:  here is a the jfiddle

What's the simplest way to add a click event handler to a canvas element that will return the x and y coordinates of the click (relative to the canvas element)?  No legacy browser compatibility required, Safari, Opera and Firefox will do.


Let's say that a being or a machine has nearly infinite amount of information, about the world around us. It could easily find the outcome of a flipped coin knowing the force it was thrown, the atmospheric pressure, etc... It could also predict the place and action for every person on earth in a year from now by calculating all the possibilities.  So the question is, is there any event that could happen that this machine has no way to predict? A trully unpredictable event no matter how much information it has?

I have recently been thinking a lot about determinism and pretty much decided there was no reason to refute it as there was no evidence of free will that I could find. However, a couple of days ago, this thought experiment came to me and it seems to be a point against determinism so I wanted to see what the SE thought:   Assume that in a few years, someone finally built the determinism computer that took every variable into account and could therefore predict the next action of everything, (including people assuming there is no free will). So I print out the page of Mr Jack Robert and it happens to say he will eat cereal in exactly one hour. In an effort to prove free will, I run over to his house and pay him 100$ to eat salami instead.   By this type of line of though, as long as I knew what the computer predicts, I should be able to do something different than what it asserts I will do every-time and quite literally make it impossible for it to make the right prediction, something impossible if there was only determinism.  Is this a good case against determinism?


Good night,  I'm using the Elsevier journal template, I need to set up a table like Image 1. I'm a beginner in TeX and I still have not understood how to merge cells into a table. Ideally, the table should be in the format of Image 2. The code I have in the template is:  \begin{table}[h] \centering \begin{tabular}{l l l l l} \hline \textbf{Author} & \textbf{Year} & \textbf{Blockchain} & \textbf{Implementation}\\ \hline {[31]} & 2018 & Ethereum & None \\ {[33]} & 2018 & Ethereum & Simulation \\ {[34]} & 2017 & Ethereum & Simulation \\ {[36]} & 2018 & Ethereum & Complete \\ {[37]} & 2017 & Ethereum & Simulation \\ \hline \end{tabular} \caption{Related Work.} \end{table}   Table from template:     Table I need:    The second image I did in Word, but it must be in the format of the template I'm using.

Here is a simple table.  I want to merge 4 cells. I want to combine the three "this" cells area in this table. I thought I have to use multirow and multicolum at same time. However, I could not find how to use it.  If possible, could you post the modified LaTeX source code?     My LaTeX code:  \documentclass{article} \usepackage{multirow}% http://ctan.org/pkg/multirow \usepackage{hhline}% http://ctan.org/pkg/hhline \begin{document}  \begin{table}[ph] \begin{center} \begin{tabular}{c|c|c|c|c} \hline \multirow{2}{*}{Raaa (k)} & \multicolumn{4}{c}{C ()} \\ \hhline{~----}  & 3.3 & 2.5 & 1 & 0.5 \\ \hline \multirow{2}{*}{Raaa (k)} & \multirow{2}{*}{this} & this & 0.5 & 0.6\\ \hhline{~~~--}            &                       & this & 0.7 & 1.2 \\ \hline \end{tabular} \caption{R, C ripple size} \label{T:peak} \end{center} \end{table} \end{document}


Currently my system runs on Windows 7. Recently I tried to install(upgrade to 8 from 7) Windows 8 twice and failed. The installation worked fine for almost the end. The installation procedure restarted my system twice and worked up to the 'Getting Devices Ready' section.  After the 3rd restart a screen with an error message showed. I can't read that error because that screen didn't even appeared for a second. When the error appeared the system restarted for 3 more times, showing the error each time.  Then the installation procedure was stopped and it reverted back the changes made. When this was completed, the system started with Windows 7. Is there any way to know why the installation was unsuccessful ? I mean, is there any log or something else about the installation details in my system ?

When I tried to upgrade 7 (standard install, primary NTFS partition), the installed stopped at 29% and gave me a message that "Installation failed".  Not even proper punctuation!  I have no idea where to look for error files and there could be a multitude of issues affecting this, so where can I look for more info.  Is there a CLI switch for something akin to verbose mode that I can pass to the installer?


I would like to validate a number column input to only accept 0.5, 1.0, 1.5 up to 25. I have set min and max value but user can enter any 1,2,3,4,6,7,8,9 after decimal place. I only want to allow .5 decimal value. I'd like a number column to codify calculations in workflow. Many thanks

Using SharePoint 2013, I have a list column of type Number, and I'd like to restrict it to either whole / half numbers, i.e. 0.5, 1, 1.5, 2, 2.5. But values such as 3.4, 2.6 wouldn't be allowed.   A choice column is unsuitable as the range users will input could go into the 100's.  Can I use custom validation on the column for this and if so how?


I have tried to use pick block on xbox but it will not get the data saved for what I pick even with other buttons.

Are you looking for how to use /setblock with blocks with data? See .  How do I get a block with data in my inventory so I can place it myself? In Java Edition, these commands work: give @s chest{BlockEntityTag:{Items:[{id:"diamond",count:10b}]}} give @s sign{BlockEntityTag:{Text1:"{\"text\":\"foo\",\"bold\":true}"}}  How can I do this in Bedrock Edition, where there is no access to NBT tags from commands?


Let me raise an example to be clear: say I have a 2*2 contingency table as follows:  5 10  10000 10000  I assume it satisfies the assumptions of chi-square test. But the proportion ~ 0.05% is very small. Will it cause a problem? E.g. the effect size can be small I suspect.

I applied a survey consisting of 12 questions to 120 people and each questions include 4 nominal categories; I want to make comparison of people's answers according to their socio-demographic characteristics such as their educational level or socioeconomic status. All of my comparison criteria consist of nominal categories and number of categories change between 3 to 6. I cannot drop or combine comparisons; categories in other words number of categories are fixed.    My question is when I compare the frequency distribution of people's answers based on their education levels (for example) through chi-squared test, I got a warning that says (for instance) 7 cells have less than count five; minimum expected count is; 43.  I got this warning for almost my all questions - demographic characteristics comparisons.    Shall I underestimate this warning and use my test results or is there a different test I should use? If I should use a different test, which one?


While applying for a UK Visa in Nigeria with my wife and kid, can we submit 4 bank statements? One of the statements is our joint business account, the second is my salary account from my part-time job, the 3rd statement is my personal and other contract job and the 4th is my wife's personal account. I hope it's okay if I submit them all since we receive money from all of them.

The UK Visas and Immigration Directorate publishes  that provides helpful tips that can result in successful visa applications. Section 2 of this guidance opens is entitled "other documents you may want to provide" (emphasis mine).  Section 2: other documents you may want to provide – all visitors This section provides guidance on the types of documents that you may want to provide to help us consider your application against the Immigration Rules. Previous travel documents/passports, which show previous travel. Financial documents showing that you have sufficient funds available.  These must clearly show that you have access to the funds, such as:  bank statements building society book proof of earnings such as a letter from employer confirming employment details (start date of employment, salary, role, company contact details) where a third party (who is either in the UK or will be legally in the UK at the time of your visit) is providing financial support to you e.g. a business, a friend or a relative, documents to show that they have sufficient resources to support you in addition to themselves and any dependant family should be provided   The first item is "bank statements" and this ties in with the , which says...  evidence that you can support yourself during your trip, eg bank statements or payslips from the last 6 months  (Note 'eg' is a Latin abbreviation meaning "for example"; this appears to be optional rather than a fixed requirement.) Question: How should someone interpret this such that the chances of success are maximized? How many statements should I submit? What are they looking for and what do my bank statements tell about me?


I'm trying to use mytheme_preprocess_html() to load a different html.html.twig file based on certain conditions (GET variables in URL).  In D7 I've done the this with:  if (isset($_GET['response_type']) && $_GET['response_type'] == 'embed') {     $variables['template_file'] = 'raw'; }   Where variables['template_file'] = 'raw'; set the name of the tpl file to load (raw.tpl.php). It works fine.  Now I need to do the same thing in D8, but I can't find the way. I tried:  function mytheme_preprocess_html(&$variables) {      if (isset($_GET['response_partial']) && $_GET['response_partial'] == 'header') {         $variables['html']['#theme'] = 'raw';     } }   But it doesn't work.  Edit  I know how to set different template for page.html.twig, but I can't figure out how to do the same for the file html.html.twig  The function   function mytheme_theme_suggestions_page_alter(array &$suggestions, array $variables) {      $suggestions[] = 'html__raw';     $suggestions[] = 'page__header'; }   Works properly for the page template but not for the html.

I need Drupal to use a custom page template if the URL contains a particular _GET parameter.  In D7 I would do something like this in the theme's template.php:  function mytheme_preprocess_page(&$variables) {       if($_GET['isCustomTpl'] == true)         $variables['theme_hook_suggestions'][] =  'page__myCustomTpl'; }   It doesn't work in D8 though (I would have been surprised by the opposite, considering all the architectural changes in the theme layer).  Any ideas?  Bonus question: is it possible to define such a function in a module, so that i can release it publicly without having the users to edit their themes?


"The universally recognized raw text format that any computer can understand." OR   "The universally recognized raw text format any computer can understand.   This is a definition for a computer science term and online, the definition includes "that". Is "that" in the first sentence redundant? I understand that in some cases "that" is necessary, like "The fish that leaped into the sea" because you're naming what the specific fish did--you're identifying it, but I encounter a lot of sentences that I think "that" is unnecessary in. ANOTHER EXAMPLE:  "The time it takes for a bit to travel." OR  "The time that it takes for a bit to travel." In my opinion, you don't need "that" because time is already the subject and you're not naming specifically what "time" is or what it did, unlike the fish sentence. Please help!!

Sometimes, the word 'that' to introduce a dependent clause is optional.  For example, these sentences both make sense with or without 'that':  Long books [that] religious people like tend to be Bibles. Water tanks [that] fish need are spacious.  ... whereas in these sentences, 'that' is mandatory and the sentence is ungrammatical without it:  Those that are rotten must be thrown away. Cars that break down endanger pedestrians.  I can't quite put my finger on the rule which determines when 'that' must be used.  What is it?


I studied that the EM waves run through the space, with each electric field and magnetic field oscillating and inducing each other. And I had thought-experiment that it could be possible to make EM waves with manual steps(or mechanical) -  shaking permanent magnet or electrificated sticks. Is it possbile enough to make EM waves in the way i assumed? If it is, please hyperlink the related research.

If I wave around a bar magnet, the magnetic field in the space around it changes. Is this enough to go through the whole speed of light derivation implying that the motion creates an electromagnetic wave? If so how do I determine the wavelength and direction of the resulting wave?


While making a template linked list, rather than having the files list.h and list.cpp, we create list.h and list.cpp.h. The .cpp.h file contains the implementation for the linked list class. At the end of list.h, before the #ENDIF, we #include "list.cpp.h".   I understand that by making the .cpp file a header file we are able to avoid compiling it, but how does this work? We have needed to compile implementations that rely on using "template < class T >" in the past, so why do we not have to compile this implementation file?   Edit: My question was marked as a duplicate with a link to  , which I had already read. That question does not answer why the template implementation does not need to be compiled like a normal .cpp implementation file does. If we can avoid compiling implementations by making them header files, why do we not do that for every implementation? What are the downsides?   Does instantiating a template compile the code for each instance of that template? If my .cpp ever requires the use of a template in one of its functions, then why wouldn't I change it to a header file if it avoids this initial compilation?  I hope my question makes more sense.

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


I have over 100 notes on my Mac from this year but stupidly I didn't put them on my I cloud as I had though it posed a securaty risk but I think I was being overly carful/paranoid.  I want to make sure there backed up encase anything happends to my Mac.  I satered moveing them manualy but I'm "lazy" so I dont want to have to move over 100 + notes manualy.  Is there a way to copy them all over at once?

I have a lot of Notes on my machine which I don't want to loose. It's not logical to export them one by one. Is there any way to export them in one go, which would make me either use them on my new   I learned that I could backup ~/Library/Group Containers/group.com.apple.notes but I am not really sure if this would be helpful. This is what I get as for this directory.  $ du -sh ./* 4.0K    ./Library 256K    ./NoteStore.sqlite  32K    ./NoteStore.sqlite-shm 3.0M    ./NoteStore.sqlite-wal   I am running macOS Mojave.


Question: Prove that $$\lim_{n\to\infty}(n!)^\frac1n=+\infty.$$  Solution 1: Let $\{a_n\}_{n\ge 1}$ be such that $$a_n:=(n!)^\frac{1}{n}, \forall n\in\Bbb N.$$ Now clearly $a_n>0, \forall n\in\Bbb N$. Also, $\{a_n\}_{n\ge 1}$ is a strictly increasing sequence. This implies that either $\lim_{n\to\infty}a_n=L,$ where $L\in\mathbb{R}^+$ or $\lim_{n\to\infty}a_n=+\infty$. Let us assume that $\lim_{n\to\infty}a_n=L,$ where $L\in\mathbb{R^+}$. Now $\forall n\in\mathbb{N},$ $$(2n)!\ge \prod_{k=n}^{2n}k\ge n^{n+1} \\\implies \sqrt[2n]{(2n)!}\ge \sqrt[2n]{n^{n+1}}=n^{\frac{n+1}{2n}}\ge n^{\frac{n}{2n}}=n^\frac{1}{2}=\sqrt{n}.$$ Therefore, we can conclude that, $\forall n\in\mathbb{N}, a_{2n}\ge \sqrt n$. Now we know that every subsequence of a convergent sequence converges to the same limit as that of the original sequence. Thus $$\lim_{n\to\infty}a_{2n}=L\ge \lim_{n\to\infty} \sqrt{n}=+\infty,$$ which is a contradiction to the fact that $L\in\mathbb{R^+}$. Therefore, we must have $$\lim_{n\to\infty}a_n=+\infty.$$ Solution 2: We know that for any sequence $\{a_n\}_{n\ge 1}$ of positive numbers, if $$\lim_{n\to\infty}\frac{a_{n+1}}{a_n}=l, 0\le l\le \infty, \text{ then }\lim_{n\to\infty}\sqrt[n]{a_n}=l.$$ Thus defining $a_n:=n!, \forall n\in\mathbb{N},$ we have $$\lim_{n\to\infty}\frac{a_{n+1}}{a_n}=\lim_{n\to\infty}\frac{(n+1)!}{n!}=\lim_{n\to\infty}(n+1)=+\infty.$$ Thus we must have $$\lim_{n\to\infty}\sqrt[n]{a_n}=\lim_{n\to\infty}\sqrt[n]{n!}=+\infty.$$ Hence, proved. Are these solutions correct? What are the other ways to solve the problem? I was looking for a solution using the Stolz-Cesaro Lemma and also one which uses the formal definition of $$\lim_{n\to\infty}a_n=+\infty.$$ Can someone provide me with the same?

How do I prove that $ \displaystyle\lim_{n \to{+}\infty}{\sqrt[n]{n!}}$ is infinite?