Which of the following sentences uses correct English grammar?   Don't make me play games I don't want to play.  Don't make me play games that I don't want to play.

He will understand that I was not joking.   He will understand I was not joking.  Which of the sentences is correct? Are there any specific rules about the use of "that" in the sentences I reported as example?


If  I demonstrated that there is no correlation between two random variables, does that mean that there is no cause and effect relation between them ?

If two variables have 0 correlation, why are they not necessarily independent? Are zero correlated variables independent under special circumstances ?  If possible, I am looking for an intuitive explanation, not a highly technical one.


In this , Freeman Dyson, when speaking of Fermi said the following thing,  "...what does he think about the numerical agreement, and he said, 'How many parameters did you use for the fitting? How many free parameters are there in your method?' So I counted up. It turned out there were four. And he said, 'You know, Johnny von Neumann always used to say, "With four parameters I can fit an elephant, and with five I can make him wiggle his trunk."  My question is that what did he mean when used the word parameter? My guess is that he is talking about the variational parameters in Wave function, but I don't get the idea how that is not allowed to be fair for precise measurements.

I was reading the article Turning Points: A meeting with Enrico Fermi by Freeman Dyson (available e.g. ), and I had a question about Dyson's use of the term 'arbitrary parameter'. More specifically Dyson relates the following interaction:     “There are two ways of doing calculations in theoretical physics”, [Fermi] said. “One way, and this is the way I prefer, is to have a clear physical picture of the process that you are calculating. The other way is to have a precise and self-consistent mathematical formalism. You have neither.”    Dyson then counters that his calculations match the Fermi's experiment, to which Fermi replies (emphasis mine)     “How many arbitrary parameters did you use for your calculations?”       I thought for a moment about our cut-off procedures and said, “Four.” He said, “I remember my friend Johnny von Neumann used to say, with four parameters I can fit an elephant, and with five I can make him wiggle his trunk.” With that, the conversation was over.   So what exactly is an arbitrary parameter in a physics calculation?


I have a basic python script that looks like this:  my_name = 'Zed' my_age = 35 my_height = 74 my_weight = 180 my_eyes = 'Blue' my_teeth = 'White' my_hair = 'Brown'  print "let's talk about %s" % my_name print "he's %d inches tall" % my_height print "he's %d pounds heavy" % my_weight print "actually, that's not too heavy"  print "he's got %s eyes and %s hair" % (my_eyes, my_hair) print "his teeth are usually %s depending on the coffee" % my_teeth  print "if I add %d, %d, and %d, I'd get %d" %(my_age, my_height, my_weight, my_age + my_height + my_weight)   I wanted to delete all of the instances of "my_" in this file so I ran the sed command:  sed 's/my_//' pythonscript.py > altered_mypythonscript.py   The outputs deleted all of the instances of "my_" everywhere except for the line at the end of the script right here:  print "if I add %d, %d, and %d, I'd get %d" %(my_age, my_height, my_weight, my_age + my_height + my_weight)   Why is sed not replacing the words in the parenthesis I want it to, and how can I fix this? Maybe my google abilities have failed me, but I haven't read anything about sed's substitute command being affected by parenthesis. I could be wrong though.

Replacing strings in files based on certain search criteria is a very common task. How can I    replace string foo with bar in all files in the current directory? do the same recursively for sub directories? replace only if the file name matches another string? replace only if the string is found in a certain context? replace if the string is on a certain line number? replace multiple strings with the same replacement replace multiple strings with different replacements


Is it possible that there are newly formed galaxies which are moving so fast that we will can't see them, even though they exist "inside" our visible universe?  I've been wondering if this could be a thing, or if I'm misinterpreting one of the following ideas.   The universe is expanding and thought to be accelerating. Galaxies past about 4,200 parsecs are expanding away from us faster than the speed of light. We are moving away from those galaxies at the same speed relative to them.   Is it possible for us to "outrun" the light from a distant galaxy, to the point where we either can't or will never see it? Something about this seems wrong, but I can't quite figure out what.

Is it true that the light from some galaxies will never reach us?   The explanation for that is that the Universe expanding faster than the speed of light. But, if the speed of light is constant in all reference frames, then in the reference frame of a galaxy, light must move at the speed of light and thus it must reach us (?).   Could you also explain  how is it possible that the Universe is expanding faster than the speed of light if an object can never be observed to move faster than light? (without Doppler effects).


a='0123456789'  >>> a '0123456789'   >>> a[1:-6:1] # working as expected '123'  >>> a[2:-1:-1] # i was expecting '210' as answer based on start index=2 end index=0 ''   Please help in understanding how the second slice operator returned nothing

I need a good explanation (references are a plus) on Python's slice notation.   To me, this notation needs a bit of picking up.   It looks extremely powerful, but I haven't quite got my head around it.


How do I find the coordinates of the centre / centroid of a raster?   I have tried Zonal Geometry but this does not give me the coordinates.  I need to find the centroids of two rasters and create points and measure the distance and bearings between them. i.e. distance and direction between two raster centroids.  I am using ArcGIS Desktop 10.2.

If I have, say, a rectangular and georeferenced raster file loaded in an ArcMap 10 document (.tiff w/ associated tfw), how do I easily find its centre point and store that point in a points vector layer?  Also, if I have multiple such rasters in my ArcMap document, how do I apply the process to all of them?  Unfortunately, I have zero Python experience. Therefore a programmatic solution is OK, but I will need specific instructions on how to load an existing script into ArcGIS 10, and run it on the rasters in questions. (BTW, the rasters are all in their separate layers).


Is it neccessary to create a placeholder lock object to for thread-safety (and correctness) or is it sufficient to lock on the resource itself (assuming no other code will need it).  locking a System.Random  private static readonly Random rnd = new Random(); public static int Rand(int min, int max) {     lock(rnd) {         return rnd.Next(min, max);     } }   using a separate placeholder/dummy lock object  private static readonly Random rnd = new Random(); private static readonly object rndLock = new object() public static int Rand(int min, int max) {     lock(rndLock) {         return rnd.Next(min, max);     } }   this may seem trivial but i'm concerned with if the first code-block is susceptible to deadlock or other issues

The  says that public class SomeObject {   public void SomeOperation()   {     lock(this)     {       //Access instance variables     }   } }  is "a problem if the instance can be accessed publicly". I'm wondering why? Is it because the lock will be held longer than necessary? Or is there some more insidious reason?


How would I go about showing this?  Suppose $R$ is a commutative ring, $A \in R_n$, and the homomorphism $f: R^n \to R^n$ defined by $f(b) = Ab$ is surjective. Show $f$ is an isomorphism.  (Edit: $R_n$ is the ring of $n\times n$ matrices.)  I'm thinking that since $f$ is surjective on $R^n \to R^n$, for every $x \in R^n$, $x = Ab$, so that $f^{-1}(x) = A^{-1}x$. And since the inverse of any element in a ring is nonzero, $\ker(f) = 0$.  I'm not terribly confident with my answer though. Thanks!

My Problem: Let $M$ be a finitely generated $A$-module and $T$ an endomorphism. I want to show that if $T$ is surjective then it is invertible.    My attempt: Let $m_1,...,m_n$ be the generators of $M$ over $A$. For every $b = b_1 m_1 + ... + b_n m_n$ with $b_i \in A$ there is $a = a_1 m_1 + ... + a_n m_n$ with $a_i \in A$ such that  $$ T(a)=b $$ or in matrix-vector notation $$ T \vec{a} = \vec{b} $$ where $\vec{x}$ is the column vector of $x_1,...,x_n$ where $x = x_1 m_1 + ... + x_n m_n$. I multiply by the adjugate matrix to get $$ \mathrm{adj}(T) \vec{b} = \mathrm{adj}(T) T \vec{a} = \det(T) I_n \vec{a} = \det(T) \vec{a} \ . $$ Now take $\vec{b}=0$. Then $\vec{0} = \det(T) \vec{a}$ and thus $T$ is injective if and only if $\det(T)$ is not a zero divisor.   If I prove that $T$ is injective, then I'll get it is invertible. For that, I think the way is to prove that $\det(T)$ is not a zero divisor.  The importance of finitely generated condition:  Let $M = A^{\aleph_0} =\{ ( a_1 , a_2 , ... ) \mid a_i \in A \}$ be a not finitely generated $A$-module. Let $T : M \to M$ defined by $$ T(a_1, a_2, a_3, ... ) = (a_2, a_3, ... ) \ . $$ Then clearly $T$ is surjective but not injective ($\ker T = \{ ( a , 0 , 0 , ... ) \mid a \in A \}$), and thus not invertible.  The importance of surjective and not injective condition:  Need to find a counter-example.


I would like to convert an Array of Strings into an ArrayList of ArrayList, where the inner ArrayList has a dynamic number of elements. Who can help ? Thanks in advance  String[] sentences = {"hello","how are you","i am fine","and you ?","thank you"} //Output with number of elements = 2 ["hello","how are you"] ["i am fine","and you ?"] ["thank you"] //Output with number of elements = 3 ["hello","how are you","i am fine"] ["and you ?","thank you"]

I have an array that is initialized like:  Element[] array = {new Element(1), new Element(2), new Element(3)};   I would like to convert this array into an object of the  class.  ArrayList<Element> arraylist = ???;


Between the two sentences, which one is more accurate and why?  Grammarly vs Prowritingaid – Which is to Choose? Grammarly vs Prowritingaid – What to Choose?

Today I found myself in a situation that I asked "Which class" to a friend who said that "we are going to the class". Then one of my friends said that I should ask "what class" and another one said both (what class and which class) are correct. Who is right?  This issue I meet often when I'm talking about things, such as:      What day/ which day?      What floor / which floor?      what teacher / which teacher?      What page / which page?      What place / which place?      What line (bus) / Which line?      What /which sentence (do you agree with)?


The question is simple. I am working on a topic. I came across a paper that is behind a paywall which my research institution (i.e. university) has no access to it and it may or may not be relevant to my research. If I skip it and some reviewer says that work is quite close to the work I have submitted and I should cite it, or even worse it is so close that it is on the edges of plagiarism.   I have the option of obtaining it from different sources without paying. Should I take it to avoid such claim? If I pay there is a good chance that I wasted money. In today's world literature is so vast and there are so many false positives and a paper might cost up to 40 bucks.  Let me flip that question. Suppose I created a publishing firm. I and my mates do superb research and publish on a journal of our publishing firm. (Assume our research quality is good, so omit academic nepotism.) One catch, our firm charges and exorbitant fee (say millions) for granting access to libraries and universities. Then we start waiting. When I see other research quite similar to ours, I press charges that our work has not been cited or acknowledged and the situation is plagiarism. I am the academic equivalent of a patent troll, except that you cannot see my work until I sue you. Should the poor guy suffer a plagiarism charge just because I kept my research behind a paywall that he/she cannot reach?  Professors and other academic people I ask about it pretend to be either unconscious or dead. Just kidding, they usually offer to send the papers that I cannot reach. But it does not answer my question.  p.s. There is a similar question here citing the problem but not the ethical dilemma.   EDIT due to possible duplicate reports: There are three questions which all refer to the same problem: unfettered access to academic research. I paraphrase and summarise three questions below. Suppose there is a body of research (say, group of articles) that are beyond the researcher's reach due to lack of resources (no ILL, no institution access, no sufficient budget etc). Should the researcher take the "gray" ways to obtain it? If not is he/she responsible for research he/she does not have access to? If so, where do we draw the line? How much is too much to pay to access research? (hence the publisher question) It is not the 80s anymore. Research is published almost faster than one can read and it is readily available (at an inflated cost). So, thorough examination of literature to conduct original research is unjustifiably more expensive than before.

When I am at home and looking for journal articles I often find article PDFs  through google that have been uploaded to various websites (e.g., universities, institutions, arbitrary websites, etc...).   I am worried that using these files may infringe copyright since these articles may be bought by these universities (for example) and (by mistake?) were freely uploaded to their domain name like: www.university.edu.lb/journal_article1.pdf (probably for their own students?).   Is it ethical to use these downloaded PDFs during my research without going back to my own university elibrary to use them? When, if ever, would I be breaching copyright or breaching professional ethics if I accessed these files?   EDIT: my question also covers books as, sometimes, these are entirely available on some sites (whether they are institutional sites or not).


My intuition as to why the statement is true is that the binomial distribution with the higher probability will always have more weight 'further right' if you were to plot it, however I can't turn this notion into a proof.   An equivalent statement is that $$\Pr[A = 0] + \cdots + \Pr[A = k - 1] \leq \Pr[B = 0] + \cdots + \Pr[B = k - 1].$$ All this is saying is that the binomial distribution with the lower probability as more weight 'further left'. Inductive arguments seem to go nowhere...   Any help would be much appreciated.

Let $X\sim B(n,p_h)$ and $Y\sim B(n,p_\ell)$ be two random variables following a respective binomial distribution, where $p_h>p_\ell$. I want to show that  $$P(X\ge\alpha)\ge P(Y\ge\alpha),$$ for any $\alpha\in\{0,1,\dots,n\}$. In other words, I want to show  $$P(X\ge\alpha)=\sum_{i=\alpha}^{n}\binom{n}{i}p_h^i(1-p_h)^{n-i}\ge P(Y\ge\alpha)=\sum_{i=\alpha}^{n}\binom{n}{i}p_\ell^i(1-p_\ell)^{n-i}.$$  The statement to be proven is obviously true, but proving it is extremely difficult (at least for me). Can anyone give me some guidance on proving it?  It would be nice if someone can give an algebraic proof too, that is, show that  $$\sum_{i=\alpha}^{n}\binom{n}{i}p_h^i(1-p_h)^{n-i}\ge \sum_{i=\alpha}^{n}\binom{n}{i}p_\ell^i(1-p_\ell)^{n-i}.$$  Thank you very much!


I have a problem with a hard drive mounted on /media/data.  This drive is mounted by means on the following command in the /etc/fstab file:  /dev/sda7 /media/data ntfs user,nosuid,exec,nodev  0  0   The partition is mounted and there is no problem using everything (working with documents, viewing movies, deleting files, moving files from any other space to this drive...). The problem is on the mode of all the files and folders in the hard drive, including the folder where it is mounted (/media/data). If I run ls -la in the media folder I get the following for this folder:  drwxrwxrwx   1 root root 8192 Jun 30 18:20 data   and the terminal displays it this way (I have the force_color_prompt=yes in my ~/.bashrc file). my folder view in color terminal:    while if I do the same in the home folder, I get:  drwxr-xr-x   2 apalomer apalomer    4096 Jul 11  2015 Public   and it is displayed this way. normal folder view on color terminal:      As you can see, there is an obvious difference. Basically what happens is that all the files and folders in /media/data are drwxrwxrwx or -rwxrwxrwx (depending on weather or not they are directories) rather than drwxrwxr-x or -rwxrwxr-x as the ones I've created in the home folder are.  I don't know if this problem is related to how I mount the drive or the fact that some day I did something not really inteligent like (or at least it does not seems right now that I am a better ubuntu user, I don't remember when or what the command whas exactly):  sudo chmod 777 /media/data   To solve this, I've tried changing the permissions individually by using:  sudo chmod --reference=   giving any file or folder in the home directory as reference. I've also tried to set the mode of the files manually using:  sudo chmod 775   for both, files and folders. However the files and folders do not change their permission. The only way I've succeed to change the mode is (and I've tested only with one file) by coping the file to the home directory, an then changing the mode there. However, as soon as I put this file back in its original place in /media/data it recovers the old mode.  Any idea on how to solve this issue?  Thanks!!  EDIT  In adition to the commets made by @Rinzwind. I've found . By mouting the partition as it is explained here, hence changing the options in /etf/fstab from the above to the follwing ones:  /dev/sda7 /media/data ntfs-3g uid=1000,gid=1000,umask=0022,sync,auto,rw 0 0   I've solved the issue of the dipsplay:    and now it is displayed as like this:

I have a script that I need to execute on an NTFS partition. The script's permission is set to 600.  I attempted to modify the permissions by running chmod 755 script.sh, which doesn't report a failure or anything - but it also doesn't change the permissions on the file:  $ stat script.sh    File: `script.sh'   Size: 297070      Blocks: 584        IO Block: 4096   regular file Device: 811h/2065d  Inode: 35515       Links: 1 Access: (0600/-rw-------)  Uid: ( 1000/  xxxxxx)   Gid: ( 1000/  xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700  $ chmod 755 script.sh $ stat script.sh    File: `script.sh'   Size: 297070      Blocks: 584        IO Block: 4096   regular file Device: 811h/2065d  Inode: 35515       Links: 1 Access: (0600/-rw-------)  Uid: ( 1000/  xxxxxx)   Gid: ( 1000/  xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700   As you can see, it remains unchanged.


I cut open a purple cabbage and there are some strange sort of greyish, slightly yellowish sprout-like masses inside. Is this normal? I saw another  but my 'masses' look more...moldy, I guess? Is it immature flower shoots as the other post says?  Is it safe to eat this cabbage? Thank you in advance

My wife cut a head of red cabbage in half and found this yellow and white organic mass inside it. We never saw anything like it before. Can anyone tell me what it is? Would it have been safe to eat? Could we have just cut off this portion of it and used the rest? We ended up playing it safe and throwing the whole head away.


I have a problem calculating the 0x02 value of the AES S-Box.  I followed the steps descibed in “”, but my answer is not correct.  0x02 is 00000010  Input = 0  0  0  0  0  0  1  0 (LSB First) Row 0 = 1  0  0  0  1  1  1  1 Bit 0 = 0  0  0  0  0  0  1  0 = 1  Row 1 = 1  1  0  0  0  1  1  1 Bit 1 = 0  0  0  0  0  0  1  0 = 1  Row 2 = 1  1  1  0  0  0  1  1 Bit 2 = 0  0  0  0  0  0  1  0 = 1  Row 3 = 1  1  1  1  0  0  0  1 Bit 3 = 0  0  0  0  0  0  0  0 = 0  Row 4 = 1  1  1  1  1  0  0  0 Bit 4 = 0  0  0  0  0  0  0  0 = 0  Row 5 = 0  1  1  1  1  1  0  0 Bit 5 = 0  0  0  0  0  0  0  0 = 0  Row 6 = 0  0  1  1  1  1  1  0 Bit 6 = 0  0  0  0  0  0  1  0 = 1  Row 7 = 0  0  0  1  1  1  1  1 Bit 7 = 0  0  0  0  0  0  1  0 = 1   LSB is 11100011, MSB = 11000111, than (XOR) to the final vector 0x63, the result is 0xa4, but it should be 0x77  What am I missing or what might I be doing wrong?

I'm trying to understand how the AES S-Boxes are calculated. I understand how the multiplicative inverse is calculated over $GF(2^8)$, but I'm confused by the description of the affine transformation. I haven't been able to Google a good explanation of how the S-Box values are calculated. Can someone explain how this works, starting after the calculation of the multiplicative inverse?


I have this code   \documentclass{article}  \usepackage[demo]{graphicx}  \begin{document}  \subsection{Local Analysis: Steady State A}      \begin{figure}[ht!]     \centering     \includegraphics[width=70mm]{local_Analysis.jpg}     \caption{Local Analysis}     \label{local_analysis_A}     \end{figure}  \end{document}   As you can see the figure is after the \subsection command, but when i compile my document it appears before the subsection. Can someone help me on this ?   Thanks

Is there any package or a method to force LaTeX to keep floating environments like table and figure closer to where they are declared?


Why i'm getting false in below statement. int x = 10;     System.out.println("X="+x=="X="+x); //false  If i'm right then after evaluation it will look like below statement.. System.out.println("X=10"=="X=10"); //true  And why i'm getting true in this.. final int y = 10; System.out.println("Y="+y=="Y="+y);

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


Let's say if some one has Ubuntu server 12.04 should he reinstall and put 16.04 or just update the security updates??? This is just an example.  I want to hear more opinions on this. What is a normal thing to do. I think there is no more linux servers online serving a website with ubuntu 8.04. It needs to be reinstalled at some point. Maybe it's not reinstalled? Maybe it can be upgraded? What is the standard procedure?

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


We are an academic lab that developed several online servers. Is there a way we can have people ask questions about the servers, and answer them directly on a Stack Exchange site (, for example)? We would use tags, but none of us have enough reputation to start one.

I recently saw a question about a problem (or possible bug) with some product on Stack Overflow. At first, I wanted to suggest that the asker post his question to that product's support forum.  When searching for the URL of that forum, I noticed that the product developer closed its support forums and now advises users to post all their questions on Stack Overflow instead.  Is this within the intended use cases of Stack Overflow, or is this abuse?


Compare:       We're all aware that our content is licensed under CC-BY-SA.  DL-AUT is not licensing its content thusly (content falls under the © 2015 dluat.com at the bottom) and is also implicitly claiming authorship of the content (going by Dicol – search that word on the page).  There is a Source link available at the bottom of each post (though not on any ), but the common-sense implication is still there.

of Stack Overflow, all content posted on Stack Exchange sites by their users (i.e. you wonderful people) has been provided to the whole universe under . For my fellow non-lawyers, that license basically means:   Anyone can use any Stack Exchange posts at any time without having to ask for permission Making money off of the copied content is permitted You don't even have to copy stuff from here verbatim; you can just use it as a starting point and make whatever edits you want There are just two rules you have to follow:   You have to provide . Simple links to the original post and author info are just fine. You have to  and allow other people to use your content, as long as they follow these very same rules. How meta!    (If you ever forget any of that, and want to refresh your memory, the license info is linked to in the footer of every page.)  There are, in fact, a lot of people who republish varying amounts of our content for assorted reasons. Unfortunately, there are some Stack Content Republishers Attributing Poorly and/or Excelling at Ranking (SCRAPERs, for short).  In this context, "attributing poorly" means any use that doesn't follow our attribution rules or make any other reasonable attempt at give credit. This can get pretty egregious; I've seen SCRAPERs that not only don't link back to SE originals, but also use fake author info and post dates to make it harder to find originals. By "excelling at ranking," I'm referring to copycat sites that end up higher in Google results than the original SE sites do for the same content. That's not necessarily wrong, but in some cases, it indicates inappropriate SEO hackery.  So, the question is: what can you do if you spot a SCRAPER?


In the Two Towers movie, when Aragorn and company meet the newly reincarnated Gandalf the White, he has the following conversation with them     GANDALF VOICEOVER: From the lowest dungeon to the highest peak...... I   fought with the Balrog of Morgoth. Until at last I threw down my   enemy......and smote his ruin upon the mountainside. Darkness took   me......and I strayed out of thought and time.Stars wheeled   overhead......and every day was as long as a life age of the Earth.   But it was not the end. I felt life in me again. I've been sent   back...... until my task is done.   Why is Gandalf speaking like he is one of the mortal men? As a Maia, Gandalf's spirit or  is his primary form and therefore, after the destruction of his physical body, the ëala should have survived on and returned to Aman from where he originally came. We see it described this way in the cases of both Sauron and Saruman except that they don't return to Aman. That is, when their bodies die, their spirits rise out of the mortal remains and are "blown" away.     To the dismay of those that stood by, about the body of Saruman a grey   mist gathered, and rising slowly to a great height like smoke from a   fire, as a pale shrouded figure it loomed over the Hill. For a moment   it wavered, looking to the West; but out of the West came a cold wind,   and it bent away, and with a sigh dissolved into nothing.   -Scouring of the Shire, RoTK   But Gandalf here doesn't remember the details of what happened after he died because he has just been reincarnated again. But that goes against much of what Tolkien thought about the Maiar. For a Maia, their spirit or ëala exists independently within the world and the physical forms they assume are just like clothes put on and cast off at will. But here, why is Gandalf talking like he was expecting his physical death to be the permanent end - "It was not the end. I felt life in me again"?

Given that the Ainur, like the Elves were bound to the universe as long as it lasted, only men being able to escape (the gift of men), why on the death of his Earthly form did Gandalf leave time and get sent back by Eru, rather than simply travel to the Halls of Mandos for healing and reclothing in valinor?     'Naked I was sent back- for a brief time, until my task is done'. Sent back by whom, and whence? Not by the 'gods' whose business is only with this embodied world and its time; for he passed 'out of thought and time'. Naked is alas! unclear. It was meant just literally, 'unclothed like a child' (not disincarnate), and so ready to receive the white robes of the highest. Galadriel's power is not divine, and his healing in Lorien is meant to be no more than physical healing and refreshment."   [The Letters of J.R.R. Tolkien, (#156)]


I have tried this: sudo apt install nodejs  Getting Error this:  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  nodejs : Depends: python-minimal but it is not going to be installed E: Unable to correct problems, you have held broken packages.

After upgrading from 10.04 to 12.04 I am trying to install different packages.  For instance ia32-libs and skype (4.0).  When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message.   Output of commands:  sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.   After running this:  sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.


I'm currently working on timestamps that are converted from and to UTC. All articles that I found were based on conversion to and from String.   SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); simpleDateFormat.setTimeZone(TimeZone.getTimeZone("UTC")); Date myDate = simpleDateFormat.parse(rawQuestion.getString("AskDateTime"));   But I wonder if there is a way to simply work with the Date instance/class or the calendar to convert the local Date into UTC and vice versa without converting it to String in between.

I have a Timestamp value that comes from my application. The user can be in any given local TimeZone.  Since this date is used for a WebService that assumes the time given is always in GMT, I have a need to convert the user's parameter from say (EST) to (GMT). Here's the kicker: The user is oblivious to his TZ. He enters the creation date that he wants to send to the WS, so what I need is:  User enters: 5/1/2008 6:12 PM (EST)  The parameter to the WS needs to be: 5/1/2008 6:12 PM (GMT)  I know TimeStamps are always supposed to be in GMT by default, but when sending the parameter, even though I created my Calendar from the TS (which is supposed to be in GMT), the hours are always off unless the user is in GMT. What am I missing?  Timestamp issuedDate = (Timestamp) getACPValue(inputs_, "issuedDate"); Calendar issueDate = convertTimestampToJavaCalendar(issuedDate); ... private static java.util.Calendar convertTimestampToJavaCalendar(Timestamp ts_) {   java.util.Calendar cal = java.util.Calendar.getInstance(       GMT_TIMEZONE, EN_US_LOCALE);   cal.setTimeInMillis(ts_.getTime());   return cal; }   With the previous Code, this is what I get as a result (Short Format for easy reading):  [May 1, 2008 11:12 PM]


I installed Windows 8.1 on the same hard disk partition as windows 7. Now I have this problem - I cannot remove Windows 7 from this boot screen. How to do it? Thanks in advance!

I bought a laptop recently. While Windows 7 was installing, the battery died. So I plugged in the charger and re-installed Windows 7 Home Basic from the start. After completion of the procedure I now have 2 Windows folders in my C:\ drive, so I deleted the old Windows folder.  The problem is, while booting time it shows two Windows 7 options, although I already deleted the old Windows folder.  How can I remove old Windows 7 option from my boot?


Ubuntu 18.04 LTS gives me three choices for my GeForce GT730 card.   Noveau (opensource) NVIDIA driver metapackage / nvidia-driver-390 (closedsource, tested) NVIDIA binary driver - version 340.106 / nvidia-340 (closedsource)   I know that nvidia driver is better for gaming, but which one ? "Driver metapackage" or "binary driver", What's the difference ? What does it mean "metapackage" in this case ? Thank you.

I've heard some packages being classified as a meta-package. So now I am left wondering what is the difference between a meta-package and a package?


I have Ubuntu 20.04.1. I do have KDE Plasma 5.18.5 desktop environment. Does anyone knows if KDE Plasma 5.18.5 will Upgrade to KDE Plasma 5.19 for Ubuntu 20.04.1 ? I do have the PPA too.

Why are packages in the official Ubuntu repositories older than the latest (upstream) versions from Debian Sid, PPAs, the authors, etc.?


An external script that I use, generates divs of a certain class from time to time, it can happen unlimited amount of times. I'm trying to run a function each time such element is being created. I tried using $('selector').live(function(){}) and $('selector').waitUntilExists(function(){}) but it's only valid for the first time it's created. how can I create some kind of a listener that will call a function each time a new element of this class is being created?  Thanks

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


If a cradle-snatcher is someone middle-aged or older who has a romantic or sexual relationship with a much younger partner. What do we call the much younger person in that relationship? What do we call a person who is physically and romantically attracted to much older people?

What do I call someone who marries or has a sexual relationship with someone much younger than themselves? Their partner is someone who is at least 18 years old.    The term paedophile is not the correct word, because it refers to minors.


Something close I have considered, but is not correct, is "Bite the hand that feeds you". The reason this is not correct is because this simply means someone (actively) treats their helper poorly, whereas the situation I want to cover is the person completely ignores or snubs them. I am looking for an idiom if possible that means completely snubbing someone that once helped you, especially someone the perpetrator depended on, or had a lot of frequent contact with before, but only because the perpetrator wanted to use the helper for their own benefit and advantage, then abandoning them / disowning them after they are no longer of any help to the perpetrator. Not looking for an idiom or word that describes the person (which would be an adjective), rather, I'd like a word or phrase that is a verb. Thanks

There is an idiom in Persian that literally says: "(to be ignored right after) somebody's donkey has crossed or passed (over) the bridge"  We use it in situations where someone (now feels relieved and) ignores or treats us much differently after:   We have helped them to overcome or reach a solution to a problem, but as soon as they feel relieved, they start treating us as if we are now strangers or even annoying to them! (i.e. They totally forget the help they received.)  We have provided them with something they needed (like a piece of information or news, a confirmation, an acceptance or agreement, money, etc), but since their need has been met, they don't think twice about ignoring us.   As you know, donkeys are stubborn and when they perceive danger, you can't force them to do anything. So I think the origin of this idiom might have been like this: someone's donkey refrained from crossing the bridge, so they asked a friend to help them get the donkey over the bridge, but after being on the other side, they forgot about their friend or treated them ungratefully.  Example scenarios:   Your friend calls and desperately asks you to lend a large sum of money otherwise they will go to jail. They promise to pay back the sum in two months. You lend the money and they say you are their best friend. After three months they still haven't paid you back. You need the money, so you call and ask them when they would repay it.  They promise the following month! A month goes by and still no sign.  So you call them again on the 6th month. They get angry and scold you about why you have called them over that trivial (!!) sum of money and ask you not to waste their precious time with these annoying phone calls since they would definitely pay you back as soon as possible! At this point you say:      "Okay, you are talking like this because your donkey has already passed over the bridge and you feel safe and relieved now, but are you sure it was your last problem??! I will never help you anymore even if you are about to be executed!"    Joe and Jane have been dating for five years, during all those years Joe's behavior has been exemplary; he really wanted to marry her (so he was just acting according to Jane's wishes and requests). After Jane accepted his proposal of marriage and they got married, Joe started to show his other side and gradually ignored Jane's requests. So Jane told him sarcastically:      "Oh, yeah! now that you've got my "yes", you are ignoring me and the reason is clear: your donkey has just crossed over the bridge!"   Is there any equivalent idiom, expression or proverb in English to criticize such people?


Let be the non empty set $G$ with the operation $*$ satisfy the following 3 conditions:  $a(bc) = (ab)c$, for all $a, b, c \in G$ (associative law). For every $a,b$ there is $c$ such that $ac = b$. ($c$  is the "path" from $a$ to $b$). For every $a,b$ there is $d$ such that $bd = a$. ($d$ is the "path back" from $b$ to $a$).   Prove or disprove: $G,*$  is a group.  Asociativity: Proof: from 1) Identity element: Proof: According to 2) For every $a,a$ there is $e$ such that $ae = a$. Let proof $ea=a$. According to 2) For every $e,e$ there is $X$ such that $eX= e$. Let's check the two possibilites:  $X=a,$ $X\neq a$  If 1) then $ea=a$ proved. If 2): $eX=e$ then what? Every try failed. Someone can do it?

Motivation: If operation is change, and there is no change, then there is no operation. Then the meaning of  1+0 =1 is not in the equality itself but in the comparison with other equalities as  1+2=3. The following definition does not use the meaningless equality  1+0 =1, or generally a*e=a. I guess that trying to prove statements using the next definition, matters/problems will arise that do not arise with the standard definition. Let be the non empty set G = {a,b,c,d,.....z} with the operation *, satisfy the following 3 conditions:  a(bc) = (ab)c, for every a, b, c ∈ G (associative law). For every a,b there is c (unique) such that ac = b. (c  is the "path" from a to b). For every a,b there is d (unique) such that bd = a. (d is the "path" back from b to a).  P.S.: the meaning of 2) and 3) is the possibility to "go"/"move" from any member to any member, through the same path (if a->b->c then c->b->a as in the Klein group) or through other path (if a->b->c then c->X->a). Prove: G,*  is a group. Proof: Associativity: From 1) Identity element: Let's prove for every a there is e such that ae=ea=a. Proof: According to 2) For every a,a there is e such that ae = a. (3) According to 2) for every e,a there is x such that ex=a, that means ae =ex =a (4) Let's proof x=a. Multiply by a on the left, such that the result is some g ∈ G: ae = ex = a (4) <---> (a)ae = (a)ex = aa =g <---> aae = (ae)x = aa =g (associative) <---> <---> aae = ax = aa =g (3). (5) According to 2) for every a,g there is x (unique) such that aa=g and ax=g , then a and x are the same, and it's proved x=a. Then replacing in (5): ae = ea = a. Inverse element: Let's prove that for every a, there is b such that a ⋅ b = e and b ⋅ a = e According to 2) for every a,e there is b such that ab = e. (6) According to 2) for every b,e there is X such that bX=e. (7) Let's proof that X=a ab = bX = e (6),(7) Multiply be a on the right: aba =ea a(ba) = ea; Associativity ea = a; Identity element a(ba) = a; then ba = e bX=e according to (7) ba = bX = e; according to 2) for every b,e there is x unique such that bX = e then x=a and it's proved that for every a, there is b such that a ⋅ b = e and b ⋅ a = e.


So, I've gotten the candy from the drop game, and I know what it does (allows you to view previous answers by friends). I plan on using it to see more of my friends questions (right now I can only see 2 from each friend) but I can't figure out how to use it. Anyone know how?

In the Miitomo Drop game, if you don't get one of the special items, you get 3 pieces of candy.   So far I haven't found anything that I can do with this candy - what use does it have in-game?


All my length are in millimetres and the command \the\mylength outputs a length in points. Idem with the \layout from the package layout.  How can I display all theses lengths in millimetres (more easily understandable than the points).

I am using various macros that I have fine-tuned with units like pt and cm. I use those macros normally in certain places (say, in main body text or in footnote text). To properly generalize those macros, I would like to replace the absolute units by relative ones.  Say I have a macro \newcommand*{\aalso}{\textsl{and also}\hspace{1.1pt}}. Say I normally use that macro in footnotes. But now I realize that I made a mistake and would like to change the length 1.1pt to something of the form ...em so that I can use the macro elsewhere. How do I get the right number? I assume that the right way is to define some macro like \emConverter{1.1pt} that, if issued in a footnote context, gives me the length of 1.1pt in a footnote context converted to a relative length in em. It doesn't need to be a LaTeX-parsable value; it's okay if this is just printed out directly into the document, for me to then manually write the new em-value into the source code.  Some relevant questions:


I mean, could it have been earthquakes or anything else?

As you probably know gravitational waves seem to have been proven unless you've been living under a rock for the past day. The experiment involves the reflecting off mirrors and waves of light and it is best you look because it is a little bit complicated but not too difficult. The effects are very subtle, and I am wondering if they could be a result of any Earth movements or activity above the Earth's surface. However, it seems most likely that if it is not gravitational waves, it is Earth movements because the experiment took place deep underground. Is there any proof that this is not a result of Earth movements and the only possible explanation is gravitational waves?  I don't want to be the stick in the mud here and spoil the party. However, I do like to know that what we are seeing is the truth as the effects require highly advanced equipment to be observed.     After reading all the great responses, the proof that gravitational waves do exist appears rock solid, and it seems Einstein was right again.


In a game I'm working on, I have an advancement system that is supposed to trigger based on exponent levels:    function machinesOwnedAdvancement(machine,machineLevel) {   if (machine >= Math.pow(2,(machineLevel+5))) {     console.log(machineLevel);     machineLevel += 1;     console.log("Machine is upgraded. It is now level: " + machineLevel);   } }     The function will be called as such:  machinesOwnedAdvancement(scribes, scribesAdvancementLevel);   Where scribes is number of machines owned, and scribesAdvancementLevel is initially = 0. The idea is that it 'should' add 1 to the advancement level. The console.log suggests it does, but when the next game tick occurs (i.e. the function is called again), the console.log(machineLevel) is still at 0.  Maybe I'm mistaken about how function arguments can be used to manipulate variables??

The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).  Although it doesn't really matter at the end, I want to know what is the correct way to present the arguments passing conventions. Is there an excerpt from JavaScript specification, which defines what should be the semantics regarding this?


I have the Xiaomi Mi A3 and I'm currently on both phone and PC latest stock update. I am using Windows 10 20H2 and I have tried everything – but still don't get it. I tried another Mi A3 and it got attached normally. I've tried installing all kind of drivers and different ports, nothing. When suddenly it worked and I installed the stock ROM – but because the stock ROM is kinda laggy and ugly I want to change it. But I can't because I am also on stock recovery and I can't install another recovery because my device isn't recognized in fastboot mode. My device is recognized in adb mode and in edl mode as well, only not in fastboot.


How do we solve an equation of this form: $ax + by = z$ for integers. For example: $45x - 37y = 25$ My try: $45x \equiv 25 (mod 37)$ $9x \equiv 5 (mod 37)$ $45x \equiv 5 + 37 \cdot 4 (mod 37)$ $9x \equiv 153 (mod 37)$ $x \equiv 17 (mod 37)$ How we continue from here to arrive to the final answer formally? And until here it's correct?

Find all integer solutions to $7595x + 1023y=124$  Using the Euclidean algorithm I have found the $\gcd(7595,1023)=31$ and found the Bezout identity $31=52\cdot1023-7\cdot7595$ but I'm not really sure how to go about finding all solutions to that equation.   I believe you can divide the equation through by the $\gcd$ - which gives $245x+33y=4$ - but I'm not sure what to do next.


I booted up Ubuntu, noticed I had no internet.  Ran ifconfig, eth0 is now eno1 and has no IP.  I ran dhclient eno1, no DHCP server found.  Went to check 70-persistent-net.rules, it's gone.  I rebooted and tried to regenerate it, no luck.  I am kind of a linux noob and this problem is driving me crazy.  oh, and /etc/network/interfaces only has lo, no other interfaces listed.  I haven't pasted any command outputs because as I said, no internet.  If need be I will manually type out terminal outputs, but I don't want to have to do excessive typing.  Any and all help is greatly appreciated, thanks.  UPDATE: WiFi is working now, although it cuts out every 10-15min and the interface has the be brought down and up to reconnect.

I updated a virtual machine running Ubuntu server 15.04 to the just released new stable 15.10.  There were no apparent problems, but after reboot the machine lost its network connection. lspci showed the correct card and lsmod proved that the driver had been loaded.  Hints about editing or removing /etc/udev/rules.d/70-persistent-net.rules did not succeed (still no network, no new file), the famous /lib/udev/write_net_rules did not even exist.  I don't have much clue regarding udev and systemd, so it took me some time to find in /sys/class/net that the network interface name changed. It became ens32, which was renamed from eth0. After I changed /etc/network/interfaces network communication was enabled again.  But - why does this happen at all? And if it happens, shouldn't the interfaces file be updated automatically?  Now that I deleted the virtual network card and created another one, eth0 becomes eno16777728, which is not so, uhm, nice.  Should this behaviour (at least that of the upgrade procedure) be reported as a bug?  Furthermore, is /etc/udev/rules.d/70-persistent-net.rules obsolete now? And (although only partly related) what about /etc/udev/rules.d/70-persistent-cd.rules?)  Edit - additional question (after accepted answer) The dependency of /etc/network/interfaces from the actual interface name bothered me. I tried a new installation of *ubuntu in another virtual machine. To my surprise, /etc/network/interfaces contained a reference to the loopback device only. However, with my original VM this change prevented the network to come up. So what else do I need to change?  Edit Well, from another test I found that a new Ubuntu Server has the network interface card in /etc/network/interfaces, while XUbuntu has not. Maybe it is using network-manager or something else.


After reading an answer on how to , I tried to do it myself.  I made a new document, entered the following and saved.  #! /bin/bash  echo "this is a test"   I then went to Right-Click > Properties > Permissions and checked "Allow executing file as program."  However, when I double-click the document, it simply opens in my text editor (which I believe is gedit). In the right-click menu I see no options for running the file in the terminal.  I've tried doing this with other files as well. For instance, I installed WINE and tried to install a Window's program. WINE said to simply run the installer, but nothing would happen when I tried. I marked it to run as a program and still it wouldn't work. I could only install it by Right-Click > OpenWith and selecting WINE.  Strangely enough, I copied my Keepass-2.28 Portable folder from my Windows partition to my Ubuntu partition and tried running the executable. Keepass fired right up, even though I hadn't marked that file to run as a program. I have Keepass 2.25 from the repository installed on my system if that makes a difference.  I've been running Ubuntu 14.04 in a dual-boot setup for several weeks. The only thing I can fathom I did that would mess this up is I used Synaptic Package Manager to remove a package from KDE Desktop Environment in an attempt to uninstall an alternate desktop environment I installed via the terminal. I don't remember what the package was, but the only package in that category right now is appmenu-qt5. As far as I can tell, removing that package has affected nothing, and I'm pretty sure I had issues with running files as programs since I got my Ubuntu.  EDIT: I have checked, and I don't think this question is a duplicate of . My Ubuntu is on a ext4 partition, and it's from there I'm trying to run programs. I also haven't dealt with trying to change permissions via the terminal or anything like that, I'm just trying to make the program run when I check the option in the properties menu. Please correct me if I'm wrong or missing anything.

When I double-click on a script in Nautilus to run it, the script just opens in my text editor with no option to run it. Using Nautilus, how do I run executable text files and/or scripts?


Is there a list of new software/site features?  Maybe a chronological list of links.  Or are there too many to list, or don't you care to publish them?  I'm thinking of this for example:   If I didn't just happen to be reading Meta, I wouldn't know that new feature existed -- and would I ever discover it?  Maybe there is a list and I don't know that the list exists, nor where.

This is an unofficial list/changelog of new features and various changes to Stack Overflow and the Stack Exchange network.  It is maintained by the community, while a Stack Exchange employee changes the accepted answer to ensure that the latest changes remain on top (given default user settings).  To see the list in reverse chronological order (latest entry on top), .  For those adding new features here: please post only feature changes that affect the whole network and have some global impact. i.e. bug fixes don't belong here, nor do mobile app updates.


In another sheet I want to count how many meetings were scheduled for a rep within a date range.  My 3 columns are the date, rep, and misc data  =countifs( "https://docs.google.com/spreadsheets/d/1q87c_0rFdt8FcWtIzD0KVW3k1ZpuvhfeWb1281MEs”, ”DEMOS!A2:C1000", B2:B="Rep1", A:A,">=11/9/2019", A:A,"<=11/15/2019")   I'm a bit off it seems and I keep going around in circles.  Here is an example. I only want to count if Dates are between 11/9 and 11/15 and if the Rep is Rep1       A         |B ------------------- Date      | Rep ------------------- 11/8      | Rep1 11/9      | Rep2 11/14     | Rep2 11/15     | Rep1

I'm trying to create a GDocs spreadsheet to collate data from a survey. I'm fairly new to the advanced features of GDocs/Excel but here's what I'd like to achieve. I've tried Googling but it's a tough thing to search.  I currently have a COUNTIF formula that looks like this:  COUNTIF( 'Survey Data'!F2:F200; "Divisional Exec" )   This works fine. But I would like to refine that. So I want to count the number of times a string appears when COLUMN A = 'ACT' and when COLUMN F = 'Divisional Exec' in the same row.  Is this possible to do in Google Spreadsheets? If so how do I do it?  I have tried  but can't seem to get it to work for me.


Given a JS string: var s = "deep.deeper.deepest", how can I convert this into object like this: deep: {deeper: {deepest: {}}}

I have this string  'john smith~123 Street~Apt 4~New York~NY~12345'   Using JavaScript, what is the fastest way to parse this into  var name = "john smith"; var street= "123 Street"; //etc...


Note: There's several answers on SE on how best to spread taint already, but none appear to pertain to Thaumcraft 4 specifically, with the old solutions being incompatible.  So, for the purpose of sabotage, experimentation, etc. How does one spread taint, or create a taint zone in Thaumcraft 4?

I spawned near a huge section of taint, and I'm fairly sure it's spreading.  My panicking in  turned up the suggestion of turning off the spreading in the config file, so I dug out Thaumcraft.cfg, and found this:  # The chance per block update (1 in n) of the Taint biome spreading.  # Setting it to 0 prevents the spread of Taint biomes. I:biome_taint_spread=0   So...it seems like it's not spreading?  Now, either I'm going crazy or there's something else causing it to spread.  Could Tainticles and the like (tainted spiders, creepers, etc) cause it to be spreading?  In what ways can the taint spread?


I'm trying to reference two figures, but somehow the tagging mechanisms is not working properly. I have done this thousand of times, and it's driving me crazy. I have come to the following minimal example:  \documentclass[a4paper,12pt]{article} \usepackage[english]{babel} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc}  \begin{document}  \section{Section name}  Reference to Fig. \ref{fig:1}.  Reference to Fig. \ref{fig:2}.   \begin{figure}   \label{fig:1}   \centering   \rule{10cm}{5cm}   \caption{xx} \end{figure}  \begin{figure}   \label{fig:2}   \centering   \rule{10cm}{5cm}   \caption{xx} \end{figure}   \end{document}   And the output I get looks like:    What am I doing wrong here???

\documentclass{article} \usepackage{algorithm}  \begin{document} \setcounter{section}{54} \section{A section with no label} \begin{algorithm} \label{myalg} \caption{An algorithm with the label `myalg'.} \end{algorithm} Reference to myalg: \ref{myalg}. \end{document}   With this code, the reference givens 55 (the section number); if I move the label after the caption command, I get the correct reference (1).  Why should this be the case? I find it confusing: when thinking about an algorithm as an environment, you expect to be able to label it right after you began it. At the very least I would expect some kind of error or "??" to appear, rather than the previous environment or reference-able entity being used.


I have edited the pages and categories to all look the same and have a right sidebar, so when I click to a page or category they are same layout and also search results and archives and tag archives.  However when I click on the post title or posted on date the layout is different (no sidebar).  Does anyone know how I can make this look the same as other pages/categories with the right sidebar or which file I need to edit in the directory?

I am using 2011 theme, any how I managed to get sidebar on single.php pages by installing child theme,  But now I want sidebar on pages,  How do I get it?


I would like to know how can I redirect the stdout of an app to an input of an another app but still see the app1 output.  The source app is written in c, the second app is in perl. The purpose of this, that i would like to interpret the output of the C program with the perl script, and do something based on the input. The problem is if i use the ./c_app | ./perl.pl, so use the | pipe, i can only see the output of the perl script. It's like the perl would swallow the output of the C_app.  I've tried to use the tee, and found some examples, but all of them are based on redirecting the output of the source app to a file, not to an input of an other application.  The below figure illustrate the process, the got and the expected result.   A limitation would be that I cannot modify the C app, nor the perl, so i would solve it by using linux stuffs. Is it possible to use the same terminal to see both output? I have no idea how to solve it.  Any recommendation, bash script, etc. would be appreciated.

I have a script that outputs text to stdout. I want to see all this output in my terminal, and at the same time I want to filter some lines and save them in a file. Example:  $ myscript Line A Line B Line C  $ myscript | grep -P 'A|C' > out.file  $ cat out.file Line A Line C   I want to see output of first command in terminal, and save the output of the second command in a file. At the same time. I tried using tee, but with no result, or better, with .


When I click on an XML feed in Firefox it automatically detects this and asks how I would like to subscribe. Is there an easy way to just see the raw feed in Firefox?  This is simple in Google's Chrome browser, since it doesn't do anything. But I am guessing a future version will handle it as Firefox does.

Internet Explorer has this option, Turn on feed reading view:    When unchecked, clicked  feeds will show as raw XML.  How can I do the same thing in Firefox?


I am getting an error on Ubuntu 20.04 while installing Zoom-client. "error: snap "zoom-client" has "install-snap" change in progress"  Is it happening because I cancelled sudo apt upgrade?

I just finished the installation of the Ubuntu 18.04, but whenever I try to install any application from Ubuntu Software the same error occurs (for example "vlc"):     unable to install "vlc": snap "vlc" has "install-snap" change in progress   I hope somebody can tell me what I've done wrong.


I have an question that is confusing me, I tried to search on internet but no clear answer... Questions : How can i determine the equation of a conic given 4 or 5 points example : Given the points  A(1,1) B(0,2) C(-3,0) D(2,1) E(1,2) How to write the equation of conic passing through the points ( A,B,C,D ) ?

How do we find the equation of a conic given five points on it?   Is there a quick method, such as some determinant; which may help solve for the equation easily?  Of course, one may just substitute the given 5 points in the general equation of the conic, and solve for the unknowns - but that method is very time consuming and exhausting.   Could someone please help me generate a matrix, whose determinant gives the required equation of the conic?  Data available: Coordinates of 5 points on the conic.   Thanks in advance!   P.S. I've successfully generated a determinant for the equation of a circle, given three points on it.   Here's the link to where I first found it, and later proved it -


I am trying to implement a iDisposable class in c# but the examples in msdn and stackoverflow do not works for me.  And im running a console application in visual studio 2012 framework 4.0  am I missing some using or what?  public class Foo : IDisposable {     public void Dispose()     {         Dispose(true);         GC.SuppressFinalize(this);     } }   I am following this examples (hyperlinks dont works for me, dont know why):

I know from reading  that the "primary" use of the IDisposable interface is to clean up unmanaged resources.  To me, "unmanaged" means things like database connections, sockets, window handles, etc.  But, I've seen code where the Dispose() method is implemented to free managed resources, which seems redundant to me, since the garbage collector should take care of that for you.  For example:  public class MyCollection : IDisposable {     private List<String> _theList = new List<String>();     private Dictionary<String, Point> _theDict = new Dictionary<String, Point>();      // Die, clear it up! (free unmanaged resources)     public void Dispose()     {         _theList.clear();         _theDict.clear();         _theList = null;         _theDict = null;     }   My question is, does this make the garbage collector free memory used by MyCollection any faster than it normally would?  edit:  So far people have posted some good examples of using IDisposable to clean up unmanaged resources such as database connections and bitmaps.  But suppose that _theList in the above code contained a million strings, and you wanted to free that memory now, rather than waiting for the garbage collector.  Would the above code accomplish that?


I need to show there is an unique complex number $z \in D(0,1)$ such that $ze^{\lambda-z}=1$ where $\lambda>1$. I know already, from the intermediate value theorem, there is an $z \in ]0,1[$ that satisfies this. How do I prove this z is unique in $D(0,1) \subset \mathbb{C} $? Thank you!

Let $a \in \mathbb{R}, a>1,$ and consider the equation $$ze^{a-z}=1$$ How many solutions does this equation have in the unit disk, and how many of those solutions are real?   My attempt to solve was to use the Argument Principle on the function $f(z)=ze^{a-z}-1$, in hopes of recovering the number of zeroes that way. The integral I attempted to compute for this was $$\int_{|z|=1} \frac{e^{a-z}-ze^{a-z}}{ze^{a-z}-1}dz=\int_{|z|=1}\frac{1-z}{z-e^{z-a}}dz$$  I do not know how to proceed from here, as the $e^{z-a}$ in the denominator seems problematic. Thanks for your help!


It seems like there isn't, apart from programmatically changing the first two items of the words array using DFusion(as indicated by the following ). However that question is a bit old, so I was wandering if anybody came up with anything new?  The reason why I would like this is that I would like to easily indicate familial bonds(who's whose family, using patriarchal rules for surname inheritance). It doesn't make sense to me for a child of a bloke to not bear their surname.  A work around could be created by using the nickname field as dynasty name holder, and selecting to display the nickname in the middle.

I can add, change and remove the nick names of my Dwarves (or any other playable and currently played race) easily; that's one of the functions of the unit screen. This visually replaces the first name of the Dwarf in this list and a few other places, but their actual first name stays and is being used in places like combat reports and so on.  I'd like to be able to rename the Dwarf in question instead, both first and last name (the last name so that I can have children inherit the last names of their parents, as strange as it may sound to a real Dwarf). I couldn't find anything in the game itself and the most commonly used DF admin tool - Dwarf Therapist - only allows changing in the nick name.  Is there a way to do it? Ideally in-game, but using external programs is fine too, especially if I don't have to shut down the game to do so.


Does anyone have a source, formula, or calculator for the current carrying capacity of laser drilled micro vias?  I haven't found anything great yet.  I'm sure it depends on plating too.  Is there a difference between copper filled, conductive filled and open or non-conductive filled?  For example I'll probably use a 5mil laser with a 2-3mil dielectric and conductive fill them and plate flat.  Oh and I did ask my vendor but haven't heard back...  edit: I don't think this is a duplicate of how much current a via can carry because a laser drilled via structure is different than a drilled via.  In fact I've read in multiple places that they carry more current than a traditional via so I was looking to see if anyone had an answer.

As I know, there exist limits on maximum current, a pcb via can tolerate before it melts before the via's temperature rises unacceptably high above ambient (say 10-100 C above ambient depending on application).   What are standard values or rules of thumb for the maximum current (or current density) through a pcb via?  PS: the question is about DC, but any additional considerations (if any) for a high frequency current are welcome as well.


I have this photo before and after being blurred (From Macphun software ad):    I dont know about you but for some reason the blurred version almost makes the island look like it is an intricately created miniature. I am not sure why.  I have seen this effect used in the Game of Thrones intro as well as some games but I cant explain how it works. Why does our brain perceive size differently in these scenarios?

This question isn't so much about how to achieve the effect of making a scene look like it's modelled in miniature, but why tilting the focal plane creates the effect. What is it about photographing miniatures that makes them look like miniatures, and how is this replicated by tilting the focal plane?  I can understand how when photographing a model of a scene, you have a much higher magnification, which leads to a shallower depth of field compared to when capturing the real-sized scene, but how does tilting the focal plane help? Is it just that you have the focal plane tilted relative to the plane that most of your subject is on, so that you can achieve a narrower depth of field for the focal length and aperture, or is there more to it than that?


I have offers for vps and dedicated hosting.  The price for dedicated server is around $100/month which makes me think whether I am really getting a dedicated machine or just scammed to give me vps in the name of dedicated server.  Is their anything windows 2008 specific that we can check whether is a dedicated machine or vps?  Something from device manager or remote bios or something of that sort?  Note -    answer could not be to ask the provider as I want to believe on facts rather than words. Nothing great can be identified from lan like ipconfig /all nor any of the linux commands works on windows shell. As a technology believer No should be last thing we have :)

Is there a way to know if the Windows machine I'm working on is virtual or physical? (I'm connecting with RDP to the machine. If it's a virtual machine it is working and handled by VMWare).


Almost all of the orbits of planets and other celestial bodies are elliptical, not circular.   Is this due to  by other nearby massive bodies?  If this was the case a two body system should always have a circular orbit.  Is that true?

This might be a completely wrong question, but this is bothering me since many days ago. Given the mass (Sun) curves the space around it, gravitation is the result of such curved space (Correct me if I am wrong, source: A Documentary film). Given any point on a circle with center same as center of the mass, curvature in the space should be equal (Intuition).   Planets rotate around the Sun because of the curve in the space they should follow a circular path and the distance between planet and Sun should be at a distance.  Given the fact that earth has a elliptical orbit around the sun, and the distance between Earth and Sun varies according to position of the earth. Why do we have a elliptical orbit not a circular orbit.


It's very basic, but I am confused as to what regression actually is in the case of econometrics. What is it useful for? Why do we use it instead of other methods? I understand that one of the main ideas of statistics is to make generalizations about a population from samples of data, but how does regression relate to this? And what is regression analysis?

An embarrassingly simple question -- but it seems it has not been asked on Cross Validated before:   What is the definition of a regression model?    Also a support question,   What is not a regression model?   With regards to the latter, I am interested in tricky examples where the answer is not immediately obvious, e.g. ARIMA or GARCH.


I'm using php 7.3 but my string not show as well: <?php header('Content-type: text/plain; charset=utf-8'); // mb_internal_encoding("UTF-8");  var_dump($_POST); //it shows ØªØ³Øª var_dump($_GET); //it show as well   my result:

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


I want to use QGIS and processing to run some tasks that would be redundant to do by hand. When I try to run a script as a stand alone I get the error      AttributeError: 'module' object has no attribute 'runalg'   When I use runandload in place of runalg, I can run the script, but only from within QGIS software. Do you know what I need to do to run the scripts as a stand alone? Below is my code, I'm using QGIS 2.8.6-Wien. I am new to Python in QGIS and if there's a better/more powerful library, let me know.  import processing  # Set variables polygon_path = "/home/pathtopolygon.shp" line_path = "/home/pathtoline.shp" explode_path = "/home/explode.shp" result_path = "/home/result.shp"  # tools general.runalg("qgis:polygonstolines",polygon_path,line_path) general.runalg('qgis:explodelines',line_path,explode_path)

In the discussion from a question I asked several days ago (), someone suggested that I use general.runalg() instead of processing.runalg() for running QGIS algorithms.    I've now used both, and haven't noticed a difference in either performance or syntax between them.  I'm just wondering what sort of differences there are between these two methods, and which one I should be using.


I want to know if a mac user uses Time Machine so I can tell him it's a good habit to do backups. So I need to detect if either:   user never activated Time Machine last backup is very old so it's like they are not a regular Time Machine user    I've looked into tmutil but I'm not sure which command would be the most reliable for me to use.   tmutil latestbackup doesnt seems to be a good source of truth for that tmutil listbackups doesnt seems to be a good source of truth for that tmutil destinationinfo maybe? I can't test on a Mac that never used Time Machine to see the output

I know i can get the time stamp of the latest Time Machine backup with the command tmutil latestbackup | grep -E -o "[0-9\-]+$" but this only works when my backup disk is plugged in. If not, i get the error message Unable to locate machine directory for host.  Is there any other way to figure out (through scripting) when the last backup was made?   I'm running OS X Mavericks and the use case would be to eventually run this as remote monitoring for Macs, say, using collectd.


I have a work visa (PhD program in Switzerland) starting from December 20 2015-March 19 2015. It is my understanding that during this time, I must obtain my residence permit which allows me to remain/leave/return to Switzerland after my visa expires. I would very much like to purchase a flight on December 15th, 5 days before my visa is valid. As an American, I can travel to Switzerland as a tourist for 3 months without a visa. Would it be acceptable to go there on the 15th as a "tourist" for 5 days until my visa is valid WITHOUT A RETURN FLIGHT? The Swiss Consulate of SF informed me that this should be acceptable, but they cannot guarantee this.

If I have a Type C visa from the Norwegian embassy valid for February 9-28, and my Type D national visa from the German embassy valid from March 1 - August 31, 2017, do I need to leave/fly out of the Schengen area on the 28th and fly back on the 1st day of March?


I want to enable reversed path filtering to prevent source ip spoofing on my server. I noticed that I have the following settings at current:  net.ipv4.conf.all.rp_filter = 0 net.ipv4.conf.default.rp_filter = 1 net.ipv4.conf.lo.rp_filter = 0 net.ipv4.conf.p4p1.rp_filter = 1 net.ipv4.conf.eth0.rp_filter = 1   The setting in all and the one in default are not the same. There are no explicit settings on my /etc/sysctl.conf file. I would like to what is the impact to the rest of the configurations between setting  net.ipv4.conf.all.rp_filter = 1   and  net.ipv4.conf.default.rp_filter = 1   Do I have to set both or just one of them?

In sysctl, the /proc/sys/net/ipv[46]/conf/ keys have the following subkeys: all, default, and a key for each network interface. For example, on a machine with a single network interface eth0, it will look like this:  iserv ~ # ll /proc/sys/net/ipv[46]/conf/ /proc/sys/net/ipv4/conf/: insgesamt 0 dr-xr-xr-x 0 root root 0 12. Sep 23:30 all/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 default/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 eth0/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 lo/  /proc/sys/net/ipv6/conf/: insgesamt 0 dr-xr-xr-x 0 root root 0 12. Sep 23:30 all/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 default/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 eth0/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 lo/   All the respective settings exist in each key separately. For example, if I want to disable IPv6 Router Advertisements with the accept_ra value, this value exists four times:  iserv ~ # sysctl -a 2>/dev/null | grep "accept_ra " net.ipv6.conf.all.accept_ra = 1 net.ipv6.conf.default.accept_ra = 1 net.ipv6.conf.lo.accept_ra = 1 net.ipv6.conf.eth0.accept_ra = 1   My question now is: which of these values do I need to change? I figured all (to change all existing interfaces) and default (to change all new interfaces that may appear later), but changing these still leaves the value at 1 for lo and eth0:  iserv ~ # sysctl -w net.ipv6.conf.all.accept_ra=0 net.ipv6.conf.all.accept_ra = 0 iserv ~ # sysctl -w net.ipv6.conf.default.accept_ra=0 net.ipv6.conf.default.accept_ra = 0 iserv ~ # sysctl -a 2>/dev/null | grep "accept_ra "   net.ipv6.conf.all.accept_ra = 0 net.ipv6.conf.default.accept_ra = 0 net.ipv6.conf.lo.accept_ra = 1 net.ipv6.conf.eth0.accept_ra = 1   Will the machine now accept Router Advertisements on eth0, or will it not?


I have recently heard the following statement:  A negative chemical potential means absence of particles.  However, I cannot make this consistent with e.g. a system of free bosons for which $\mu$ must be negative to ensure stability of the partition function.

My lecturer told me that $\mu$, the , is zero or negative, and in the following example, mathematically it acts as a normalization constant. But is there any physical insight about why boson gas can be zero or negative? I think it is due to the fact the photon gas can pop up from nowhere (i.e. vacuum fluctuation). $$ f_{BE}(\varepsilon)=\dfrac{1}{e^{(\varepsilon-\mu)/(k_B T)}-1}$$


I was trying to use sudo apt-get update to update the packages on my system but I kept encountering an error   W: Failed to fetch http://repo.mongodb.org/apt/ubuntu/dists/trusty/mongodb-org/3.4/Release   Unable to find expected entry 'multiverse/binary-i386/Packages' in Release file (Wrong sources.list entry or malformed file) E: Some index files failed to download. They have been ignored, or old ones used instead. Error executing command, exiting   I looked everywhere, did whatever was suggested but nothing seems to work. I freshly created my source.list file but it was all in vain. Can anybody please suggest me something?  In my case not only a single line of sources.list if malformed but the entrie file is showing as malformed and I have already tried the methods suggested here  but it is not working..

I have unistalled and reinstalled the Ubuntu Software Center as per info I found in a similar thread and I got the same response about line 91 or something like that.  I just tried to upload a screen shot but since I'm new it won't allow me to.  I also can not figure out how to cut and paste anything so I have to hand type what the error screen says, both when I attempt to open the software center and nothing happens, when I try to enter commands into the terminal to uninstall, reinstall, whatever I get the same following:  COULD NOT INTITIALIZE THE PACKAGE INFORMATION An unresolvable problem occured while initializing the package information Please report t:his bug against the 'update-manager' package and include the following error message: 'E: Malformed line 91 in source list/etc/apt/sources.list (dist parse)  E: The list of sources could not be read.,  E: The package list of status file could not be parsed or opened.   How do I report bugs?  What can be done about this.  I have searched and everything everyone says to do leads me back to the same line error message.  So, I don't know how to get to line 91 in the source list; to tell you what it says. Sorry, I'm really new to this. That is what I need is to find out how to get there and fix what it says. I would really like to NOT have to re partition my hard drive and start from scratch, so I'm really looking forward to getting this problem solved. I need to be able to install new software.


I have this problem but I cannot sign on to my computer, because I have no idea what password windows 10 is looking for, and it will not boot up without one. K Barbero

I got a brand new Windows 7 machine, installed the operating system, created one account and forgot its password. What can I do?  There is no external CD, the operating system is loaded from somewhere inside the machine.  I already tried to remember passwords and tried all candidates with all possible combinations of caps lock, num lock etc.


I want to call func which in iframe , from parent.  If the func is in parent I could call it like : parent.func();  but I want to call func which is in iframe and I want to call it from parent? js says I could not find func? How can I call it?  thanks

Basically, I have an iframe embedded in a page and the iframe has some  routines I need to invoke from the parent page.  Now the opposite is quite simple as you only need to call parent.functionName(), but unfortunately, I need exactly the opposite of that.  Please note that my problem is not changing the source  of the iframe, but invoking a function defined in the iframe.


I have 3 classes GrandParent, Parent and Child, where  Child extends Parent and Parent extends GrandParent  public class Main {     void test(GrandParent gp){System.out.println("GrandParent");}     void test(Parent p){System.out.println("Parent");}      public static void main(String args[]){         GrandParent obj = new Child();         Main mainObj = new Main();         mainObj.test(obj);  // This calls test(GrandParent gp)          mainObj.test(new Child()); // This calss test(Parent gp)     } }   In above code in the 2 calls to test() method both with Child object calls different methods. In one it's doing compile-time and in other run-time binding. This sounds little weird to me. How would you explain this?

Yesterday I had a two-hour technical phone interview (which I passed, woohoo!), but I completely muffed up the following question regarding dynamic binding in Java.  And it's doubly puzzling because I used to teach this concept to undergraduates when I was a TA a few years ago, so the prospect that I gave them misinformation is a little disturbing...  Here's the problem I was given:  /* What is the output of the following program? */  public class Test {    public boolean equals( Test other ) {     System.out.println( "Inside of Test.equals" );     return false;   }    public static void main( String [] args ) {     Object t1 = new Test();     Object t2 = new Test();     Test t3 = new Test();     Object o1 = new Object();      int count = 0;     System.out.println( count++ );// prints 0     t1.equals( t2 ) ;     System.out.println( count++ );// prints 1     t1.equals( t3 );     System.out.println( count++ );// prints 2     t3.equals( o1 );     System.out.println( count++ );// prints 3     t3.equals(t3);     System.out.println( count++ );// prints 4     t3.equals(t2);   } }   I asserted that the output should have been two separate print statements from within the overridden equals() method: at t1.equals(t3) and t3.equals(t3).  The latter case is obvious enough, and with the former case, even though t1 has a reference of type Object, it is instantiated as type Test, so dynamic binding should call the overridden form of the method.  Apparently not.  My interviewer encouraged me to run the program myself, and lo and behold, there was only a single output from the overridden method: at the line t3.equals(t3).  My question then is, why?  As I mentioned already, even though t1 is a reference of type Object (so static binding would invoke Object's equals() method), dynamic binding should take care of invoking the most specific version of the method based on the instantiated type of the reference.  What am I missing?


Show ($n+1$)$2^n$ =  $\sum_{i\geq 0}^{} {n + 1\choose i}i$  algebraically.  I know $2^n$ = $\sum_{i\geq 0}^{} {n\choose i}$. But how do I manipulate the $(n+1)$ to make it look like the right side?

I am trying to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$ but am not able to think something except induction,which is of-course not necessary (I think) here, so I am inquisitive to prove this in a more general way.  The left side of an identity occurs while solving another problem (concerning binomial theorem) so I am more interested in deriving the right side from the left side, else I have to remember it now onward.  EDIT: I am more interested in an algebraic proof rather than combinatorial argument or something involving calculus (however I liked  and  solution), hence I am removing the combinatorics tag.


I have a complicated interface where uploading a file is three step ( The forum is not allowing me to add screenshots of my window so please try to visualise it) step 1 click on browse tab and select a file to upload( This will create progress bar) step 2 click on start upload button Step 3 click on finish button firebug information about the elements on the page have been pasted at the bottom of the page. Id of my browse button is fileInputUploader  The code I am using to try and upload the file is ( within my test class)  WebElement upload = driver.findElement(By.id("fileInputUploader")); upload.sendKeys("C:/Users/Deepankur/Desktop/Deepankur Folder/selenium Test Cases/test12.jpg");   But it's not doing anything  I am not able to see that upload progress animation in step 2, so I can click on start upload and finish it. Any help will be much appreciated.  Here is the html for this section of my page
  <input width="110" type="file" height="30" id="fileInput" name="fileInput" style="display: none;"><object width="110" height="30" type="application/x-shockwave-flash" data="/core/webcore/swf/uploadify.swf" id="fileInputUploader" style="visibility: visible;"><param name="quality" value="high"><param name="wmode" value="opaque"><param name="allowScriptAccess" value="always"><param name="flashvars" value="uploadifyID=fileInput&amp;pagepath=/core/root/&amp;script=/core/application/pApproval/uploadify.cfm&amp;folder=//192.168.100.51/client_data/CPM_ConcretePlatform_DEV/userUploads&amp;scriptData=project_id%3D19%26client_id%3D2172%26project_file_type%3D2%26file_zone_id%3D104%26file_zone_group_id%3D17%26parent_project_file_id%3D0%26approval_rule_id%3D10%26job_id%3D519%26status_id%3D17&amp;width=110&amp;height=30&amp;wmode=opaque&amp;method=POST&amp;queueSizeLimit=20&amp;simUploadLimit=1&amp;fileDesc=Please see the list of allowed file extensions under More Help Uploading&amp;fileExt=*.jpg;*.tif;*.pdf;*.qxd;*.eps;*.psd;*.zip;*.doc;*.ppt;*.xls;*.pdf;*.mov;*.ai;*.png;*.bmp;*.ait;*.dwg;*.dxf;*.flv;*.indd;*.txt;*.inx;*.gif;*.cad;*.docx;*.xlsx;*.pptx;*.mpp;*.m2v;*.avi;*.vob;*.mpg;*.wmv;*.mp4;*.m4v;*.misc;*.ppsx&amp;multi=true&amp;sizeLimit=26214400&amp;fileDataName=Filedata"></object>

  Start Upload

This is a canonical question, intended to provide a comprehensive answer to many related questions  During the course of a Webdriver test, I want to upload files. However, this opens a native file picker, which Webdriver doesn't seem to support interacting with. How do I interact with it?


Definition:  Regression analysis is used for explaining or modeling the relationship between a single variable Y, called the response, output or dependent variable, and one or more predictor, input, independent or explanatory variables, X1 .... Xp.  from this book   What does independent variables mean in the definition?  Considering Xs to be random variables,does it mean that P(Xi|Xj) = P(Xi). BUt this would be very constrainted for anyone trying to use regression analysis as inputs tend to be dependent in most of the cases.

I'm slightly confused if an independent variable (also called predictor or feature) in a statistical model, for example the $X$ in linear regression $Y=\beta_0+\beta_1 X$, is a random variable ?


Assume I have a tikzpicture with different draw objects such as lines, circles, rectangle, shapes etc.  When I do not specify a color the default draw color is black.  My question is: how can I change the default draw color (black) for all objects in TiKZ picture (scope) to something else. So it should not change outside tikz picture.  This allow me to quickly (visually) test replacing default black with something else.  Tx

Sorry if this question sounds too elementary. I am new to TikZ, although I have experience with LaTeX.  Say I have multiple TikZ statements in a LaTeX document like the following:  \tikz\draw[line width=2mm] (0,0.1) -- (4,0.1);\hfill\textsc{\Large This is a block}%  \hfill \tikz\draw[line width=2mm] (0,0.1) -- (4,0.1);   I would like to define variables (e.g. line_thickness and line_width:  line_thickness = 2mm line_width = 4   that I could use in all such statements so that, if I want to change the parameters of my drawings in my LaTeX document, I could just change the value of my variables where I define them.  Is it possible to do this in TikZ?  I am interested in a relatively general solution, e.g. some of these variables may specify color, length, relative coordinates, etc. although a solution to addresses my particular problem above would already help a lot.  I have read the solutions in these threads:        but I don't know how to apply the answers to my problem.


When Yoda speaks, he often uses a distinctive speech pattern that differs from other characters in the Star Wars universe:  Take you to him, I will. The dark side of the Force are they. So certain are you.  Always with you it cannot be done.  Hear you nothing that I say? The very Republic is threatened, if involved the Sith are.  As anyone who’s had to read my incessant posts here will know, I’m not so many good with word rule laws. But: are there consistent grammatical rules used to construct Yoda’s distinctive speech patterns? (And for bonus points, just in case this is a thing, do they seem to shift throughout the films? Does, for example, his speech become more “Yoda-ish” in the prequels, as compared to Empire and Jedi?)

Yoda's unique speech consisting of reversed grammar is iconic.  Is there any reason he has adopted this speech pattern?  All other alien species encountered seem to have no trouble speaking normally. Why does Yoda speak in this way?


Are there any R packages that can estimate panel vector autoregression (panel VAR, or PVAR) models from pooled time-series data?  I've searched several ways and come up empty. I'm hoping I've overlooked something that you know where to find.  If you're wondering what panel VAR models are and how they might be useful,  is not a bad place to start.

I am working on vector auto-regression (VARs) and impulse response function (IRFs) estimation based on panel data with 33 individuals over 77 quarters.  How should this type of situation be analyzed?  What algorithm's exist for this purpose?  I would prefer to conduct these analyses in R, so if anyone is familiar with R code or a package designed for this purpose that they could suggest, that would be especially helpful.


From the right side to the left side: Assume a proper idea of a ring is the intersection of prime ideals, then for r$\in$ rad I, there exists n' such that $r^{n'}\in I$ thus for each prime ideal p, $p|r^{n'}$ thus $p|r$. Therefore r is still in I. Therefore I=rad I. But for another direction, I am not sure how to prove.

This is a problem from an algebra textbook.     Let $R$ be a ring, and $I$ be an ideal. If the radical of $I$ is $I$ itself, i.e. $\operatorname{rad}(I) = I$, then $I$ is an intersection of prime ideals.


Realizing my mistake of upvoting a comment on a question, I clicked the upvote arrow again to undo it. At my surprise, I received a pop-up alert saying that if I undo this upvote I won’t be able to upvote the comment again. I accepted, and to test this, I attempted to upvote it again, which was unsuccessful as expected.  Why can’t users be given a second chance to upvote comments?  I , but they only seem to cover mobile app crashes. Is that the sole reasoning?

I recently tried to un-upvote a comment, and received a message that if I did so, I would not be able to upvote it again:     Are you sure you want to undo your upvote on this comment? You will not be able to upvote it again.   Unlike , I completely understand what the message is saying. However, why am I not allowed to upvote it again? What's the reasoning behind this decision?


I want to make a table like the image below, i.e. I need to merge the cells under 12- and 1-2.  Thank you and sorry but I don't speak english (sorry for my english)  \begin{table}[ht]  \centering  \label{my-label} \begin{tabular} {|p{2cm}||p{1.3cm}|p{1.5cm}|p{2.2cm}|p{1.3cm}|p{1.3cm}|p{1.5cm}|p{1.3cm}|  }  \hline Dita/Koha & 9-10 & 10-11 & 11-12 & 12-1 &1-2 & 2-3 & 3-4 \\ [1.5ex]  \hline\hline E hene & Analiza & Topologji & Alg.Geometri & Pauza & & Algjelbra &  \\  [1.0ex]  \hline E Marte & \multicolumn{3}{| c |}{Provimi} &Pauza  & & \multicolumn{2}{| c |}{Aplikimi i Softuerit}    \\ [1.5ex]  \hline E Merkure & Analiza & Topologji & Alg.Geometri & Pauza &  & Algjelbra &\\[1.5ex]  \hline E Enjete &\multicolumn{3}{| c |}{Provimi} &Pauza  & &\multicolumn{2}{| c |}{Aplikimi i Softuerit} \\ [1.5ex]  \hline  E Premte & Analiza & Topologji & Alg.Geometri & Pauza &  & Algjelbra &  \\ [1.5ex]  \hline  E Shtune & \multicolumn{7}{| c |}{Vikendi} \\ [2.5ex]   \hline E Dielle & \multicolumn{7}{| c |}{Vikendi}    \\ [2.5ex]   \hline  \end{tabular}  \end{table}

Is it possible to create a table like this one?    The usual structure of tables I use looks like this:  \begin{table}[H]     \begin{adjustbox}{width=\textwidth,center}     % \begin{adjustbox}{center}         \begin{tabular}{lll}             \hline             \multicolumn{1}{l}{\head{XXX}} & \multicolumn{1}{l}{\head{XXX}} & \multicolumn{1}{l}{\head{XXX}} \\             \hline             \ttfamily xxx & \ttfamily xxx & \ttfamily xxx \\             \hline         \end{tabular}     \end{adjustbox}     \vspace{ - 05 mm}     \caption{xxx}     \label{tab:xxx} \end{table}


If you know me at all, or have read my profile, or have seen any of my previous questions, you might know that I am very interested in Olympiad maths and have come across many challenging maths problems, although I'm not too strong in the functions department myself. Could you please help me with the following problem? Again, any help and contributions are greatly appreciated.  For each positive integer $n$, define $f(n)$ such that $f(n)$ is a positive integer, $f(n+1)$ $>$ $f(n)$ and $f(f(n))$ $=$ $3n$. The value of $f(10)$ is?  This was a multiple choice question, and the possible answers were (A)12, (B)15, (C)19, (D)21, (E)30  Okay, so far I know that this function must be injective because it is strictly increasing, because $f(n+1) > f(n)$. I don't think that we can know yet if this function is surjective or not.  This shouldn't be too much of a hassle for most experienced mathematicians (like the users of this site) but for me it makes little sense. And I try, I really do! Just now I searched what injective and surjective means, and I finally understand that much, so... yea. Improvement.  Anyway, any help or contributions will be greatly appreciated. Thank you! :)

Let $f: \mathbb N \rightarrow \mathbb N$ are increasing function such that    $$f\left(f(n)\right)=3n$$   for any positive integer $n$.      Find $f(2017)$   My work so far:  1) If $m\not=n$ then $f(m)\not= f(n)$  2) $f(3n)=3f(n)$


I've got a question concerning fields used in RSA.  Let's use the following symbols for my example:  {p,q} = primes {e,n} = public key {d,n] = private key  I learnt that an inverse element exists if a is coprime to m.  Applied to RSA I would have guessed that e needs to be coprime to n in order to find it's inverse element, because n is used as mod. But according to the rules of RSA it has to be coprime to ϕ(n) (gcd(ϕ(n),e)=1). Why?

When choosing the public exponent e, it is stressed that $e$ must be coprime to $\phi(n)$, i.e. $\gcd(\phi(n), e) = 1$.   I know that a common choice is to have $e = 3$ (which requires a good padding scheme) or $e=65537$, which is slower but safer.  I also know that for two primes $p,q$, we have $\phi(pq) = (p - 1) (q - 1)$  Now, let me give a (simple) example:  Say I choose $e = 3$, and two random primes $p = 5$ and $q = 13$.  I can now compute $\gcd(3, \phi(5 \cdot 13)) = 3$.  This reveals that $3$ and $\phi(n)$ are not coprime. I assume this could also happen for large values of $p$ and $q$, and likewise for another $e$. I therefore assume that the RSA algorithm must check that $\gcd(e, \phi(pq)) = 1$. But let's assume it doesn't.  How does RSA become vulnerable if $\gcd(e, \phi(pq)) \neq 1$?


[assume no use of route 53 in first 2 paragraphs]  So Amazon doesn't let you point a base domain towards an elb. How do most people solve this problem? I can assume the recommended answer is going to be to host your site off the 'www' prefix. And then what? Point your base domain to an ec2 instance running a web server and all it does it actuate a 301 redirect to www?  As for whether you can actually still use the base domain without the www, is there a possible option? Really the only limitation is the fact that the record needs to be an A and not CNAME.   And lastly, I believe Amazon does actually let you use CNAME on base if all your pieces are hosted on AWS and you can use some extra service they have. Is this also something common for businesses to choose?

Suppose I have a domain, foo.com where I have a series of pages like foo.com/123 and foo.com/456 etc.  I want to use the domain and provide links without a www prefix.  These pages also will have links to other pages (and each other) without the www prefix.  I'm using Azure to host our site which is the same as EC2 in that the domain cannot have an A record because the server environment is virtualized. So both Microsoft and Amazon tell you to use CNAME records to point your domain to an A record they manage.  In the case of Azure, my CNAME record points to a cloudapp.net record (which microsoft manages):  foo.com  CNAME  foo.cloudapp.net   where foo.cloudapp.net is my domain I've setup on Azure.  I'm encountering all sorts of problems with various things like email delivery and various people not being able to load the site.  2 different nameserver providers and my hoster tells me that it violates the RFC to have a root domain be a CNAME entry which is why my problems are sporadic.  I'm surprised to hear this as you see so many sites these days hosted on EC2 or Azure, and do not use a www prefix.  How are these sites setup so that they can use just foo.com (without www prefix)?  Update: While I asked the question about EC2 or Azure, I'm specifically looking for info on Azure.


I can't do anything now. Can't catch Pokemon, can't get items. Does anyone have the same problem?

I'm level 10 on Pokemon Go. I've caught at least 150 Pokemon, and had no problems. Now, every time I try to catch a Pokemon, no matter the level, it just rolls twice in the pokeball, breaks free, then runs away. Can anyone provide some insight on how to fix this problem?


The coherent state is defined such that $a|\alpha\rangle =\alpha|\alpha\rangle $.  We can calculate the uncertainty using  $$\sqrt{\langle x^2\rangle-\langle x\rangle ^2}\sqrt{\langle p^2\rangle-\langle p\rangle ^2}$$  Substituting $$x=\frac{1}{\sqrt{2}}(a+a^\dagger)$$ and $$p=i\frac{1}{\sqrt{2}}(a-a^\dagger)$$ with $\omega=\hbar=m=1$ we find: $$x^2=\frac 1 2 (a+a^\dagger)(a+a^\dagger)=\frac 1 2 (aa+aa^\dagger+a^\dagger a+a^\dagger a^\dagger)$$  $$p^2=-\frac 1 2 (a-a^\dagger)(a-a^\dagger)=\frac 1 2 (-aa+aa^\dagger+a^\dagger a-a^\dagger a^\dagger)$$  $$\langle \alpha| x| \alpha\rangle =\frac 1 {\sqrt 2}(\alpha+\alpha^*)=\sqrt 2R(\alpha)$$ $$\langle \alpha| x| \alpha\rangle^2 =2R^2(\alpha)$$ $$\langle  \alpha| x^2| \alpha\rangle =(R^2(\alpha)-I^2(\alpha)+|\alpha|^2)$$  $$\langle  \alpha| p| \alpha\rangle =\frac i {\sqrt 2}(\alpha-\alpha^*)=-\sqrt 2 I(\alpha)$$ $$\langle  \alpha| p| \alpha\rangle^2 = 2 I^2(\alpha)$$ $$\langle \alpha| p^2|\alpha\rangle =(I^2(\alpha)-R^2(\alpha)+|\alpha|^2)$$  $$\sqrt{\langle x^2\rangle-\langle x\rangle^2}\sqrt{\langle p^2\rangle-\langle p\rangle^2}=0\ne\frac 1 2$$ Heisenberg's uncertainty principle states that this should be more than a half.  Where is the problem with this derivation?

I'm looking to calculate the expected values of a coherent state (of a harmonic oscillator) evolving in time. I know that the $x$ and $p$ expectation values are as in classical motion, but I'm wondering about $x^2$ and $p^2$.  Let's say I'm starting with the coherent state $| b \rangle$, with $b \in \mathbb{R}$, so the wavefunction is the ground state displaced by $bx_0\sqrt{2}$:  $$\psi_b (x) = \psi_0(x-bx_0\sqrt{2})$$  Or similarly the Wigner function will be   $$W_b(x,p) = W_0(x-bx_0\sqrt{2},p)$$  Now I know the expected values of $x$ and $p$ are classical:  $$\langle x(t) \rangle = bx_0\sqrt{2}\cos(-\omega t)$$ $$\langle p(t) \rangle = bp_0\sqrt{2}\sin(-\omega t)$$  But what about $\langle x^2(t) \rangle$ and $\langle p^2(t) \rangle$ and ?