I have installed an old 4Gb RAM module in my laptop and run Memtest86+ v5.01 on it. It showed some errors at addresses 44xxMb-45xxMb. This is way beyond 4096Mb. Where does the extra memory come from?    With a different 4Gb module Memtest shows no errors.

Context Feel free to skip this section. I ramble a bit. This is a desktop computer. My motherboard is a MSI P67A-C45. The two memory modules are 4GB DDR3-1333 in DIMM 1 and DIMM 3, dual channel. A few months ago, I started experiencing random graphics glitches resulting in my video drivers (nVidia) crashing and restarting occasionally. This was especially bad when hardware acceleration was used, especially in 3D FPS games, even with the 10+ year old goldsrc engine. It would also happen when playing flash videos, and occasionally when doing nothing. Most of the time, it was fine. It was only after the system had been up for a while - uptime, time since last reboot, not hibernation. Once the glitches started, I had to turn the computer off and leave it off for a few minutes. I suspected the video card - perhaps overheating? But temperature monitoring programs reported GPU temp at a nice cool 40 degrees Celsius. More recently (last week or two), when leaving the computer on overnight, I wake up to find it had BSoD'd, with a memory related error. I'm currently rerunning Memtest86+, so I can't dig up the exact error message/codes, if anyone really wants them. At the same time, some programs started crashing randomly ("xxxx has stopped working." with a close button). This would happen to Firefox and the aforementioned FPS game. I don't really run anything else, and the crashes are random. That is, they could crash immediately or run fine for the whole time I use them (several hours). The troubleshooter's nightmare. Memtest86+ On the first run, somewhere over 12 hours, I got the following results:  There's a few irregularities. Firstly, I have 2x 4GB DDR3-1333 modules in DIMM1 and DIMM3, dual channel. This is reporting DDR3-8247, whatever that is. Secondly, all the failing addresses are outside my total RAM capacity. That's not all that much help when trying to figure out which module may be failing. Evidently, at least one is failing. I reseated the modules and tried again:  As you can see, the frequencies and latencies are completely different. The latency values are much closer to what I vaguely recall seeing in CPU-Z (or was that HWiNFO32?). This test has only just started, so it's entirely possible those values changed sometime during the test. Also, considering errors only started cropping up in the later passes, is it possible that this is an overheating issue? Consider I've been using this computer for about a year now, and only in the last three or so months have things happened. My main question remains: Why is the failing addresses higher than my capacity?


The potion of clairvoyance says:  When you drink this potion, you gain the effect of the clairvoyance spell.  This is different than the potion of gaseous form and others:  When you drink this potion, you gain the effect of the gaseous form spell for 1 hour (no concentration required) or until you end the effect as a bonus action.  Emphasis mine. If a potion granting a spell effect doesn't say "(no concentration required)", must you concentration on it?

For example, is it possible to drink a flying potion and cast greater invisibility spell on myself (both spells would require concentration), so I can fly around invisible?


I have added a cube and changed its scale and position but not its rotation. I added a second cube as a child of that first cuboid.  I was hoping to rotate it but instead it just skews the second cuboid. The skew only happens in 2 out of 3 of the axes. Additionally the skew does not happen if the child cuboid is not a child of the first cuboid.  Screen shots attached below.  Skew happening in one of the two axes:    Rotation correctly occurring in third axis:    How do I rotate it in all axes? Also as Skew seems useful.  How do you control skewing it in all axes?

I'm not sure what's going on here. I have a cube which I have turned into a rectangle; it's a child of a plane which is the "ground" so that they share rotation (this is a pinball table).   To create these cubes, I just used the create => 3d shape => cube/plane option. No packages are used.   The issue is when I rotate the rectangle, the collider visibly becomes wrong.  This is before rotation:    This is after rotating on the y axis:    The collider does seem to rotate, but not at the correct amount. Can anyone shed some light as to what's going on here?  Here's the inspector and hierarchy:      I also tried making the plane a cube, it didn't change anything.


I'm trying to get my crontab to run a few rake tasks for a rails app, but it seems to always exit with the status of 127, in my syslog it look like this:  Jun  7 05:10:01 ip-10-170-122-226 CRON[15664]: (deploy) CMD (cd /home/deploy/apps/dashboard/current && bundle exec rake some:task Jun  7 05:10:01 ip-10-170-122-226 CRON[15662]: (CRON) error (grandchild #15664 failed with exit status 127)   It seems that 127 is like "command not found error" or something, so I've used the full paths to the bins even so like bundle was /usr/local/bin/bundle, The task runs fine outside of cron just running it in shell.  My crontab is simplily just:  */10 * * * * cd /home/deploy/apps/dashboard/current && bundle exec rake some:task   Does maybe my crontab need #!/usr/bin or something at the top?    update  To just test it, it does seem to run this just fine:  */1 * * * *  /usr/bin/touch /home/deploy/cron-test.txt   So that leads me to think its like a PATH varible thing, but I don't know how to get the right path vars in there, any thoughts?

This is a  about using cron & crontab.   You have been directed here because the community is fairly sure that the answer to your question can be found below. If your question is not answered below then the answers will help you gather information that will help the community help you. This information should be edited into your original question.  The answer for 'Why is my crontab not working, and how can I troubleshoot it?' can be seen below.  This addresses the cron system with the crontab highlighted.


public void  ZeichneFigur(String position) {     String[] parts = position.split("\\.");     String part0 = parts[0];     String part1 = parts[1];     int k = Integer.valueOf(part1);     if (part0.equals("gr"))         g.setColor(Color.GREEN); }           switch (k) {                  case 1:               g.fillOval(20,20,100,100);               Break;          case 2:              g.fillOval(20,30,100,100);               Break;          case 3:               g.fillOval(20,40,100,100);               Break;          case 4:              g.fillOval(20,50,100,100);               Break;          case 5:               g.fillOval(20,60,100,100); Break;}   First of all let me excuse my barbaric coding im a  beginner.  Im trying to write a short Method that takes strings of the format gr.2 that define values of the players color and the field that he is on, then paints ovals on the corresponding position. (Actually i have 40 cases, they are all the same). When i compile i get the ArrayINdexOutOfBoundsException, and i cant find out why, i understand that this means my index is out of range, but how does that happen when i enter gr.1 ?  EDIT: Changed if (part0.equals("gr")) and added break statements.

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?


On my main machine, a MacBook Pro, I have a .bash_profile file that I'd like to use unaltered on my Dreamhost linux machine. However, there's a few lines that are only applicable to macOS, such as alias mvim="/Applications/MacVim.app/Contents/MacOS/MacVim".  Is there a way in bash to test for whether it's running under macOS or Debian (or just not macOS) and only execute that above line, and a few others, when running under macOS? Whereas other questions here address how to find out which Linux distro is being used, here I only need to know if I'm running on macOS or Linux, and the solutions for knowing the Linux distro aren't available on macOS.

Say I am logged into a remote system, how can I know what it's running? On most modern Linuxes (Linuces?), you have the lsb_release command:  $ lsb_release -ic     Distributor ID: LinuxMint Codename:       debian   Which as far as I can tell just gives the same info as /etc/lsb-release. What if that file is not present? I seem to recall that the lsb_release command is relatively new so what if I have to get the OS of an older system?  In any case, lsb stands for Linux Standard Base so I am assuming it won't work on non-Linux Unices. As far as I know, there is no way of getting this information from uname so how can I get this on systems that do not use lsb_release?


It's the following part of a virtual host config that I need further clarification on:  <VirtualHost *:80>   # Admin email, Server Name (domain name), and any aliases   ServerAdmin example@example.com   ServerName  141.29.495.999   ServerAlias example.com ...   This is and example config, similar to what I currently have (I don't have a domain name at the moment).  <VirtualHost *:80> - Allow the following settings for all HTTP requests made on port 80 to IPs that this server can be contacted on. For instance, if the server could be accessed on more than one IP, you could restrict this directive to just one instead of both.  ServerName - If the host part of the HTTP request matches this name, then allow the request. Normally this would be a domain name that maps to an IP, but in this case the HTTP request host must match this IP.  ServerAlias - Alternate names accepted by the server.  The confusing part for me is, in the above scenario, if I set ServerAlias mytestname.com and then made an HTTP request to mytestname.com, there would have to be a DNS record pointing to the server's IP for this to work? In which case, is ServerAlias just basically EXTRA ServerName entries?  Say I had a DNS entry such that foobar.com = 141.29.495.999 but then I had ServerName = 141.29.495.999 and ServerAlias was empty, would that mean that although foobar.com gets resolved to the right IP, because there is no reference to accept foobar.com in ServerName or ServerAlias?  Or something. Man I'm confused.

I'm not quite clear on the difference between ServerName and ServerAlias. It looks like both of them work as host name settings, except that ServerAlias only works within the <VirtualHost> tag.  That is, I can do:  ServerName www.domain1.com ServerName www.domain2.com   or:  <VirtualHost *:80> ServerName www.domain1.com ServerName www.domain2.com </VirtualHost>   and both domains work on the same box. Can I use either ServerName or ServerAlias in this case?


Okay, so I needed to find the smallest value of n such that algorithm 100*n^2 is faster than 2^n.  [what I have tried]  So, I instantly thought '0'. But, I then realized it can't be 0, 0 implies that there are no digits being entered in the algorithm, it also implies that the program does not run or terminate.  I typed in 2^32 and got a number over 4 billion. Okay, this is good, I'm finding numbers that have 100*n^2 being faster than 2^n.  I halved that, n = 20.  I kept inserting values counting down until I got to n = 15.  I also counted up from n = 10, the answer is undoubtedly n = 15, but I have a problem . . . .I solved this using brute force and that isn't good. What if I was given a bigger number and a larger bredth of numbers?  [What I need]  I need a way of finding the value instantaneously by only doing the math, I tried using logarithms, but my answer was wrong, my knowledge of logs is a bit rusty and I need a little help.  Think of it as a student trying to solve a question on an SAT or having a timer for a test.


I have a Ruby on Rails app with two sub-sites, www.example.com/site1 and www.example.com/site2. For demonstration purpose, we need to disable site2 and only show site1. So I made some redirects in my apache virtual host conf like this  Redirect 301 http://www.example.com/site2 http://www.example.com/site1 Redirect 301 http://www.example.com http://www.example.com/site1   to be sure to always redirect to site1. Now, it would be great, if we could kinda strip out the site1 from the url http://www.example.com/site1 so that it only shows http://www.example.com, but also can handle sub sites (e.g. the "original" site is http://www.example.com/site1/cat1 and it should be displayed as http://www.example.com/cat1).   Is this possible using apache's rewrite engine? And how? I'm not sure if I have to change something inside my app, or is the request URL (that my router picks up) not modified by apache? Another solution would be, to only show the domain in the users address bar. Is this possible, and how?

This is a  about Apache's mod_rewrite.   Changing a request URL or redirecting users to a different URL than the one they originally requested is done using mod_rewrite. This includes such things as:   Changing HTTP to HTTPS (or the other way around) Changing a request to a page which no longer exist to a new replacement. Modifying a URL format (such as ?id=3433 to /id/3433 ) Presenting a different page based on the browser, based on the referrer, based on anything possible under the moon and sun. Anything you want to mess around with URL   Everything You Ever Wanted to Know about Mod_Rewrite Rules but Were Afraid to Ask!  How can I become an expert at writing mod_rewrite rules?   What is the fundamental format and structure of mod_rewrite rules? What form/flavor of regular expressions do I need to have a solid grasp of? What are the most common mistakes/pitfalls when writing rewrite rules? What is a good method for testing and verifying mod_rewrite rules? Are there SEO or performance implications of mod_rewrite rules I should be aware of? Are there common situations where mod_rewrite might seem like the right tool for the job but isn't? What are some common examples?   A place to test your rules  The  web site is a great place to play around with your rules and test them. It even shows the debug output so you can see what matched and what did not.


Using Fermat's Little Theorem, prove $1^{p-1} + 2^{p-1} + 3^{p-1} +\ldots+(p-1)^{p-1} \equiv -1 \pmod p$ where $p$ is a prime.    So we would use Fermat's theorem: $a^{p-1}\equiv  1\pmod p$  Would the proof go something like this....?  $1^{p-1} + 2^{p-1} + 3^{p-1} +\ldots+(p-1)^{p-1} \equiv 1+\ldots+1$  There would be $p-1$ many $1$'s so (i.e. $p-1=5-1=4$ so $1+1+1+1=4$)  $p-1 \equiv -1\pmod p$  $p \equiv 0 \pmod p$  Would that be right?

Using Fermat's Theorem prove if $p$ is prime, prove $1^p + 2^p + 3^p +...+(p-1)^p \equiv 0 \bmod{p}$  The two definitions of Fermat's Little Theorem is $a^p \equiv a \bmod{p}$ and $a^{p-1} \equiv 1 \bmod{p}$ but I don't know how to use this solve the problem


I am using ArcView ArcMap10 and when I clip a raster using tools/data management tools/raster/clip. The Clipped file ends up much larger than the original file.  Specifically I am trying to clip a MrSID file that is 2.6gb, the clipped file ends up being 54.gb.  I have tried playing with the environment setting and compression rates trying to convert to a JP2 with no luck.  I am fairly new to GIS.

Does anyone have experience subsetting/clipping a large NAIP imagery file in MrSID format? Some of the NAIP files we have are by county and they have really large file sizes.  The files are from the FSA .  How does it work if you subset a MrSID file? Does ArcGIS has to uncompress it first before it can proceed to clip or subset an area of interest?


When new keyword is encountered in java an object is created and a constructor is called.  So which constructor is called when an array object is created.  Eg int[] a = new int[];  We know that array are Objects.

In Java, an array IS AN Object. My question is... is an Object constructor called when new arrays is being created? We would like to use this fact to instrument Object constructor with some extra bytecode which checks length of array being constructed. Would that work?


Your are given an equation $$ ax^2+(b+c)x+d+e=0 $$ whose roots are real and  greater than $1,$ show that the equation $$ ax^4+bx^3+cx^2+dx+e $$ has at least one real root. Note that $a,b,c,d,e$ are all real numbers. I have tried to solve this question using the method of contradiction. However I was not able to make great progress. Is there any way I can solve it using the method of contradiction or any other proof strategy. I would also love to see an approach using predicate logic (only if it's possible).

If $a, b, c, d ,e$ are real numbers such that the equation $ax^2 +(c+b)x+e+d = 0$ has real roots greater than $1$, show that the equation $ax^4 + bx^3 + cx^2 + dx + e$ has at least one real root.


I'm working with files on C#, my cose is supposed to delete some lines from a file as mentioned here:   var tmpFile = Path.GetTempFileName();   var LinesToKeep = File.ReadLines(path).Where(l => l.StartsWith("removeme")==false);              File.WriteAllLines(tmpFile, LinesToKeep);  File.Delete(path);  File.Move(tmpFile,path);   but I'm getting an exception: IOException was unhandled when running my code saying:     The process can not access the file because it is being used by another process   in the instruction: File.Delete(path); How can check which process is using file, or there is another reason for my problem?

I've seen several of answers about using  or , but I would like to be able to find out in my own code (C#) which process is locking a file. I have a nasty feeling that I'm going to have to spelunk around in the win32 API, but if anyone has already done this and can put me on the right track, I'd really appreciate the help. Update Links to similar questions


I have heard of the thought experiment where someone fly off in spaceships and come back younger than their twin on earth.  But a fundamental idea behind general relativity was that motion can only be described as relative to others. Therefore, the twins would have the same relative acceleration to each other.  If we think about them as floating in space, there should be no way to tell who is doing the accelerating. So how does physics determine which one ends up younger?

The paradox in the  is that the situation appears symmetrical so each twin should think the other has aged less, which is of course impossible.  There are a thousand explanations out there for why this doesn't happen, but they all end up saying something vague like it's because one twin is accelerating or you need general relativity to understand it.  Please will someone give a simple and definitive explanation for why both twins agree on which twin is younger when they meet for the second time?


I like setting reminders using Siri (e.g. "remind me to buy milk tomorrow at 8pm").  Siri understands what I am trying to say and pretty smoothly adds the reminder. I would like this reminder to appear on my google calendar (i.e. some event starting at 8pm ending 15 minutes or 30 minutes later, with my message on the reminder).  How can I do this? I set a ton of reminders using Siri, and this would be a great way for me to get a birds eye view (and maybe a leg up) on all the stuff I have to do.  Thanks in advance!

I can get Siri to show me events on my Google Apps calendar (which I have set up as an Exchange account, to get the benefits of push email), but I can't get her to make an event on that calendar; new events keep being created on my own calendar.


I wrote a small program in bash and would like to make it executable from anywhere on my computer using a custom command. In addition, my program uses a small internal database that I would also like to have "embedded" in the program. Below is an example of my problem and what I have tried so far. Suppose my program returns the capital of a Brazilian state selected by the user. The program folder has 3 files. An internal base called capitals.csv: Capitais,Estados,Siglas dos Estados,Regiões Rio Branco,Acre,AC,Norte Maceió,Alagoas,AL,Nordeste Macapá,Amapá,AP,Norte Manaus,Amazonas,AM,Norte Salvador,Bahia,BA,Nordeste Fortaleza,Ceará,CE,Nordeste Brasília,Distrito Federal,DF,Centro-Oeste Vitória,Espírito Santo,ES,Sudeste Goiânia,Goiás,GO,Centro-Oeste São Luís,Maranhão,MA,Nordeste Cuiabá,Mato Grosso,MT,Centro-Oeste Campo Grande,Mato Grosso do Sul,MS,Centro-Oeste Belo Horizonte,Minas Gerais,MG,Sudeste Belém,Pará,PA,Norte João Pessoa,Paraíba,PB,Nordeste Curitiba,Paraná,PR,Sul Recife,Pernambuco,PE,Nordeste Teresina,Piauí,PI,Nordeste Rio de Janeiro,Rio de Janeiro,RJ,Sudeste Natal,Rio Grande do Norte,RN,Nordeste Porto Alegre,Rio Grande do Sul,RS,Sul Porto Velho,Rondônia,RO,Norte Boa Vista,Roraima,RR,Norte Florianópolis,Santa Catarina,SC,Sul São Paulo,São Paulo,SP,Sudeste Aracaju,Sergipe,SE,Nordeste Palmas,Tocantins,TO,Norte  One python file: #get_capital.py import pandas as pd import sys from unidecode import unidecode  df=pd.read_csv("capitais.csv")  df["Estados"] = [unidecode(k.lower()) for k in df["Estados"]] user_state = unidecode(sys.argv[1].lower()) answer = df[df["Estados"]==user_state]["Capitais"].to_list()[0]  print("A capital de {} é {}".format(user_state.title(), answer))  And, finally, a bash file: #!/usr/bin/bash python get_capital.py $1  An example of execution would be: bash stack.sh bahia  Output: A capital de Bahia é Salvador  What I've tried so far: I read  that it is possible to create a kind of hyperlink to the bash file so that it can be called from anywhere on the computer. To do this, I just type:  sudo ln -s PATH / stack.sh /usr/bin/stack.sh  Where PATH is the path where my bash file is currently located. This works, but it's still not what I want for two reasons. First, I still need to use the word bash before the file name. I know I can create a binary using chmod +x stack.sh (see this  for more details on this). However, what I would like to do is just use a custom command as stack instead of ./stack. In addition, although the hyperlink works and I can access my bash file from anywhere on the computer, my program itself only works in its original folder since the csv file is only there. Anyway, how do I "package" these files in a folder that is accessible from anywhere on my computer and that can be called up using a custom command?

How do I get the path of the directory in which a  script is located, inside that script? I want to use a Bash script as a launcher for another application. I want to change the working directory to the one where the Bash script is located, so I can operate on the files in that directory, like so: $ ./application


I have got a table 'payments'  user_id amount 1       300 1       100 2       100 2       100 3       10 4       200   What query should I make to display result by groups:  diapason       number 0 -10          0 10 - 100       1 100 -200       3 more than 200  2   I think I should use 'having'?

Suppose I have a table with a numeric column (lets call it "score").  I'd like to generate a table of counts, that shows how many times scores appeared in each range.  For example:   score range  | number of occurrences -------------------------------------    0-9       |        11   10-19      |        14   20-29      |         3    ...       |       ...   In this example there were 11 rows with scores in the range of 0 to 9, 14 rows with scores in the range of 10 to 19, and 3 rows with scores in the range 20-29.  Is there an easy way to set this up?  What do you recommend?


Following the steps here:  to free some space in /boot I was lazy. So instead of deleting every file seperately with sudo apt-get remove linux-image-VERSION, I typed sudo apt-get remove linux-image-3* after some time I realized that this maybe was a huge mistake and i stopped it with ctrl-c.   After a reboot I find my system with no usb connectivity, no wlan, no sound and the lowest possible display resolution. Can someone explain what I have done wrong and/or how I can fix this?

I was trying to delete old kernels, but I must have deleted all of the kernels on my Ubuntu 11.04 laptop. Is there any way to fix this via USB boot or mounting hard drive on another system?


I want to know which one is the best way to implement autocomplete in aspx forms using jquery?  What is the difference between using bsn.autosuggest and jquery autocomplete.If possible pls explain Thanks in advance.

I searched all over this site and the web for a good and simple example of autocomplete using jQuery and ASP.NET. I wanted to expose the data used by autocomplete with a webservice (and will probably do that next). In the meantime, I got this working, but it seems a little hacky...  In my page I have a text box:  <input id="txtSearch" type="text" />   I am using jQuery autocomplete, set up per their example:  <link rel="stylesheet" href="js/jquery.autocomplete.css" type="text/css" /> <script type="text/javascript" src="js/jquery.bgiframe.js"></script> <script type="text/javascript" src="js/jquery.dimensions.pack.js"></script> <script type="text/javascript" src="js/jquery.autocomplete.js"></script>   Here is where it starts to get hacky... I call a page instead of a webservice:    <script type="text/javascript">     $(document).ready(function(){         $("#txtSearch").autocomplete('autocompletetagdata.aspx');     });         </script>   In the page I stripped out ALL of the html and just have this (otherwise, various HTML bits show up in the autocomplete dropdown):  <%@ Page Language="C#" AutoEventWireup="true" CodeFile="autocompletetagdata.aspx.cs" Inherits="autocompletetagdata" %>   And in my autocompletetagdata.aspx, I am using SubSonic to query, format and return data from the database (one data item per line):  protected void Page_Load(object sender, EventArgs e) {     // Note the query strings passed by jquery autocomplete:     //QueryString: {q=a&limit=150&timestamp=1227198175320}      LookupTagCollection tags = Select.AllColumnsFrom<LookupTag>()         .Top(Request.QueryString["limit"])         .Where(LookupTag.Columns.TagDescription).Like(Request.QueryString["q"] + "%")         .OrderAsc(LookupTag.Columns.TagDescription)         .ExecuteAsCollection<LookupTagCollection>();      StringBuilder sb = new StringBuilder();      foreach (LookupTag tag in tags)     {         sb.Append(tag.TagDescription).Append("\n");     }      Response.Write(sb.ToString()); }   If you don't do a LIKE query, then it returns everything that contains a match for the character(s) you type -- e.g., typing "a" will include "Ask" and "Answer" as well as "March" and "Mega." I just wanted it to do a starts with match.  Anyway, it works and it's pretty easy to set up, but is there a better way?


I want to prove that $\sqrt{p\over p+1}$ is irrational where $p$ is any prime number.   I have been thinking about this problem for several hours without any progress.  To show that $\sqrt{p\over p+1}$ is irrational, I assume that it is rational. So there are integers $m$ and $n$ (which have no common divisors) such that $\sqrt{p\over p+1}=\frac{m}{n}$. By squaring and rearranging, I get $pn^2=(p+1)m^2$ but I am not sure how to proceed from here. I can say that $(p+1)m^2$ is divisible by $p$ and then I do not know what to do!

I would like to show that  $$\forall n\in\mathbb{N}^*, \quad \sqrt{\frac{n}{n+1}}\notin  \mathbb{Q}$$  I'm interested in more ways of proofing this.  My method :  suppose that $\sqrt{\frac{n}{n+1}}\in  \mathbb{Q}$ then there exist $(p,q)\in\mathbb{Z}\times \mathbb{N}^*$ such that $\sqrt{\frac{n}{n+1}}=\frac{p}{q}$ thus   $$\dfrac{n}{n+1}=\dfrac{p^2}{q^2} \implies nq^2=(n+1)p^2 \implies n(q^2-p^2)=p^2$$ since $p\neq q\implies p^2\neq q^2$ then  $$n=\dfrac{p^2}{(q^2-p^2)}$$  since $n\in \mathbb{N}^*$ then $n\in  \mathbb{Q}$   I'm stuck here and I would like to see different ways to prove $\sqrt{\frac{n}{n+1}}\notin  \mathbb{Q}$


I have a new SSD and used Gparted to format it to the ext3 filesystem - that went smoothly but now I can't access it.   I right click on the drive icon in Nautilus under "Devices" and check the permissions - it says that the owner is root and I don't know how to change that.

I've recently installed Ubuntu 11.10 on my laptop, but I can't do anything with my 1.5TB external drive, and my 500GB because I don't have write permission. Are there any specific commands I can use in the terminal to set the read/write permissions?  The external is NTFS, and the 500GB is ext4.


Are all the phrases below correct and if they are , what are the differences? Car's window / car window / the window of  car

Possible Duplicate:          If someone owns something I would say: Mom's car.  But if the owner is not a person, does it actually own it according to English rules or common usage? Which phrase is right?         The house windows.   The house's windows.   The windows of the house. (Or something like that.)      (Feel free to modify this question so it would be clear for other people.)


I am trying to get mods on my minecraft but the folder isn't there and so I can't get to my minecraft.jar folder... and I even looked in the version folder where someone told me the bin folder would be and it wasn't there. is there any way to get the bin folder so I can get to the minecraft.jar folder?

I have looked all over the Internet for solutions but I have got nothing.  I want to install the minepainter mod but I need a META-INF folder and a minecraft.jar.


How can I see that the maximum likelihood approach finds the parameter values of the probability distribution that maximize the probability of the observed sample? Maximum likelihood is not the maximum of probability in general because for, say, two continuous random variables $X_1, X_2$ we have $P(X_1=x_1,X_2=x_2)=0$.

In general we maximize a function   $$ L(\theta; x_1, \ldots, x_n) =  \prod_{i=1}^n f(x_i \mid \theta) $$  where $f$ is probability density function if the underlying distribution is continuous, and a probability mass function (with summation instead of product) if the distribution is discrete.  How do we specify the likelihood function if the underlying distribution is a mixture between a continuous and a discrete distribution, with the weights on each depending on $\theta$ ?


I have a form, a Google form, and I'd like to post the user's responses to a specific sheet in the Google spreadsheet. Is this possible?

I have a Google Form. I had all of my Google Form responses linked to a specific tab in my Google Spreadsheet. Somehow my form responses were unlinked from my tab. When I go to re-link my form responses to my already existing tab it only gives me the option to create a new tab in my spreadsheet.   How do I simply re-link my Google Form responses to my already existing tab in my Google Spreadsheet?


Recently I came across the concept of a , which is a smooth function $f:\mathbb{R}\to\mathbb{R}$ all of whose derivatives vanish at a given point $x_0\in\mathbb{R}$, the canonical example being  $$ f(t) = \begin{cases} e^{-1/t^2},& t\neq 0\\ 0,& t=0. \end{cases} $$  Now I wonder if such a function can in any way describe the trajectory of a physical object where $t$ is time and $f(t)$ is its position. The reason why I am not sure is as follows: If I throw a ball in the air, its velocity becomes zero at the highest point. Naively I could reason that it must stay there, because it cannot move anymore once the velocity is zero. But we all know that this reasoning is flawed, because the 2n derivative, acceleration, is not zero at this point, which is why the ball starts picking up speed again and comes down to earth.   But what if the 2nd derivative, acceleration, would vanish too, and the third, and so on infinitely. Would this mean that the ball comes to a halt at this point. And, by generalizing from the ball to any particle, that the $f(t)$ shown above cannot be the trajectory of a physical object? Rather the function would have to be constant at least on one side of the flat point?

Suppose you have an object with zero for the value of all the derivatives of position. In order to get the object moving you would need to increase the value of the velocity from zero to some finite value. A change is velocity is acceleration, so the value of the acceleration would have to increase from zero to some value. You would also need to increase the jerk from zero to some value to have a change in acceleration.  Is there an infinite series of higher derivatives of position for this to work? Or am I missing something?


How should I fix the following problem? (vision) mona@goku:~/research/code/vision/integration$ sudo apt-get install libopencv-dev python-opencv Reading package lists... Done Building dependency tree        Reading state information... Done libopencv-dev is already the newest version (4.2.0+dfsg-5). python-opencv is already the newest version (2.4.9.1+dfsg-1.5ubuntu1). You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  libopencv-highgui2.4v5 : Depends: libpng12-0 (>= 1.2.13-4) but it is not going to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution). (vision) mona@goku:~/research/code/vision/integration$ sudo apt-get --fix-broken install libopencv-dev python-opencv Reading package lists... Done Building dependency tree        Reading state information... Done libopencv-dev is already the newest version (4.2.0+dfsg-5). python-opencv is already the newest version (2.4.9.1+dfsg-1.5ubuntu1). You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  libopencv-highgui2.4v5 : Depends: libpng12-0 (>= 1.2.13-4) but it is not going to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution). (vision) mona@goku:~/research/code/vision/integration$ sudo apt-get --fix-broken install libpng12-0 Reading package lists... Done Building dependency tree        Reading state information... Done The following packages were automatically installed and are no longer required:   cpp-7 libpython-dev libpython2.7-dev libpython3-dev python2.7-dev python3-decorator python3-ipython-genutils   python3-jupyter-core python3-traitlets python3.8-dev Use 'sudo apt autoremove' to remove them. The following NEW packages will be installed:   libpng12-0 0 upgraded, 1 newly installed, 0 to remove and 92 not upgraded. 31 not fully installed or removed. Need to get 0 B/116 kB of archives. After this operation, 285 kB of additional disk space will be used. (Reading database ... 408548 files and directories currently installed.) Preparing to unpack .../libpng12-0_1.2.54-1ubuntu1_amd64.deb ... Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1) ... dpkg: error processing archive /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1_amd64.deb (--unpack):  unable to install new version of '/lib/x86_64-linux-gnu/libpng12.so.0': No such file or directory No apport report written because the error message indicates an issue on the local system                                                                                Errors were encountered while processing:  /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  I am using the solution in  in order to solve the problem in

How should I solve this problem in Ubuntu 20.04? Invalid MIT-MAGIC-COOKIE-1 keyqt.qpa.xcb: could not connect to display :0 qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found. This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.     Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.     Aborted (core dumped) Invalid MIT-MAGIC-COOKIE-1 keyqt.qpa.xcb: could not connect to display :0 qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found. This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.     Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.     Aborted (core dumped) 2224/31772MB(vision)   and $ echo $DISPLAY :0  and $ python Python 3.8.5 (default, Jul 28 2020, 12:59:40) [GCC 9.3.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import inspect >>> from PyQt5 import Qt >>> vers = ['%s = %s' % (k,v) for k,v in vars(Qt).items() if k.lower().find('version') >= 0 and not inspect.isbuiltin(v)] >>> print('\n'.join(sorted(vers))) PYQT_VERSION = 331522 PYQT_VERSION_STR = 5.15.2 QOpenGLVersionProfile = <class 'PyQt5.QtGui.QOpenGLVersionProfile'> QOperatingSystemVersion = <class 'PyQt5.QtCore.QOperatingSystemVersion'> QT_VERSION = 331522 QT_VERSION_STR = 5.15.2 QVersionNumber = <class 'PyQt5.QtCore.QVersionNumber'>  As a minimal code to reproduce this error, you can run this: $ cat test_qt.py  ''' ==================== 3D plots as subplots ====================  Demonstrate including 3D plots as subplots. '''  import matplotlib.pyplot as plt from mpl_toolkits.mplot3d.axes3d import Axes3D, get_test_data from matplotlib import cm import numpy as np   # set up a figure twice as wide as it is tall fig = plt.figure(figsize=plt.figaspect(0.5))  #=============== #  First subplot #=============== # set up the axes for the first plot ax = fig.add_subplot(1, 2, 1, projection='3d')  # plot a 3D surface like in the example mplot3d/surface3d_demo X = np.arange(-5, 5, 0.25) Y = np.arange(-5, 5, 0.25) X, Y = np.meshgrid(X, Y) R = np.sqrt(X**2 + Y**2) Z = np.sin(R) surf = ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap=cm.coolwarm,                        linewidth=0, antialiased=False) ax.set_zlim(-1.01, 1.01) fig.colorbar(surf, shrink=0.5, aspect=10)  #=============== # Second subplot #=============== # set up the axes for the second plot ax = fig.add_subplot(1, 2, 2, projection='3d')  # plot a 3D wireframe like in the example mplot3d/wire3d_demo X, Y, Z = get_test_data(0.05) ax.plot_wireframe(X, Y, Z, rstride=10, cstride=10)  plt.show()  $ python test_qt.py  Invalid MIT-MAGIC-COOKIE-1 keyqt.qpa.xcb: could not connect to display :0 qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found. This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.  Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.  Aborted (core dumped)  Also, $ python Python 3.8.5 (default, Jul 28 2020, 12:59:40)  [GCC 9.3.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> from PyQt5 import QtCore, QtGui, QtWidgets >>>


So my linux experience started off by abandoning windows for a week and trying ubuntu 17.04.  then i wanted to switch back to windows so i downloaded an iso file to put it on my flash drive using etcher and when i tried to boot the flash drive it always booted ubuntu instead.  so idiot me had the idea of deleting the ubuntu partition so i did that and then rebooted and im stuck in grub rescue it says:  error: file'/boot/grub/i386-pc/normal.mod' not found. entering rescue mode... grub rescue>

I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.


Does the applicability of VIF vary based on the parameter estimation process? For example, can I use VIF to check for multicollinearity if the parameters in my logistic regression are estimated using the Maximum Likelihood method or non-linear least squares for example?  When I look at the VIF formula it appears to me that it should be applicable for any regression, linear or non-linear given that the dependent variable itself isn't in the actual equation. However, surely the parameter estimation process plays a part in whether is multicollinearity or not?

Say we have a binary classification problem with mostly categorical features. We use some non-linear model (e.g. XGBoost or Random Forests) to learn it.    Should one still be concerned about multi-collinearity? Why? If the answer to the above is true, how should one fight it considering that one is using these types of non-linear models?


I plot a graph using pgfplots package. I want to change the location and size of the legends in the plotted graph. The code and graph are attached.  \begin{figure} \begin{tikzpicture} \begin{axis}[     xlabel={Nodes},     ylabel={Power (m/W)},     width=9.6cm,height=8cm,     xmin=0, xmax=7.7,     ymin=0, ymax=1.80,     xtick={0,2.2,3.3,4.4,5.5,6.6,7.7},     ytick={0,.20,.40,.60,.80,1.00,1.20,1.40,1.60},     legend pos=north west,     ymajorgrids=true,     grid style=dashed, ] \addplot[     color=red,     mark=square,     line width=2pt     ]     coordinates {     (2.2,.15)(3.3,.15)(4.4,.15)(5.5,.15)(6.6,.15)(7.7,.15)};     \addplot[     color=blue,     mark=triangle, line width=2pt     ]     coordinates {     (2.2,.52)(3.3,.49)(4.4,.52)(5.5,.51)(6.6,.48)(7.7,.49)};     \addplot[     color=green,     mark=*, line width=2pt     ]     coordinates {     (2.2,.97)(3.3,.93)(4.4,.96)(5.5,.98)(6.6,.93)(7.7,.96)};     \addplot[     color=yellow,     mark=x, line width=2pt     ]     coordinates {     (2.2,1.22)(3.3,.98)(4.4,1.01)(5.5,1.10)(6.6,1.02)(7.7,1.09)};     \legend{LPM, CPU, Radio Listen,Radio Transmit} \end{axis} \end{tikzpicture} \caption{Analysis of Power Consumption} \label{} \end{figure}

I have the following code that produces a line chart:  \begin{figure}[p]     \centering \begin{tikzpicture}     \begin{axis}[     use units,     cycle list name=exotic, %This defines the color. It produces nicer colors         width=15cm, height=8cm,     % size of the image         grid = major,         grid style={dashed, gray!30},         %xmode=log,log basis x=10,         %ymode=log,log basis y=10,         xmin=0,     % start the diagram at this x-coordinate         ymin=0,     % start the diagram at this y-coordinate         %/pgfplots/xtick={0,5,...,60}, % make steps of length 5         %extra x ticks={23},         %extra y ticks={0.507297},         axis background/.style={fill=white},         ylabel=Time,         xlabel=Number of Datapoints (n),         y unit=s,y unit prefix=m,         tick align=outside]        % import the correct data from a CSV file       \addplot table [col sep=comma,trim cells=true,y=Best Case (Ascending)] {datasets/time_mergesort.txt};           \addplot table [col sep=comma,trim cells=true,y=Average Case (Random)] {datasets/time_mergesort.txt};                     \addplot table [col sep=comma,trim cells=true,y=Worst Case (Descending)] {datasets/time_mergesort.txt};                      \legend{Ascending,Random,Descending}     \end{axis}  \end{tikzpicture}     \caption{Mergesort Run Time for Sorting Random Data}     \label{fig:merge_sort_from_csv} \end{figure}   And at the moment the legend appears on the chart on the upper right corner. I need to move that below the chart, or even to leave that on the chart but to move that on the upper left corner.   I have tried the solution mentioned at , but it did not work for me.  How can I move the axis in a different position?


I want to grab multiple lines in a file with a pattern that has a starting and an ending tag in an ungreedy way.  For example I have the following input:  file.txt  START test1 test2 foo END some more text  START test3 bar test4 test5 END even more  START baz test6 END   Now I want to look for bar and print out everything between START and END, so that I will get:  START test3 bar test4 test5 END   What I have so far is the following grep command:  grep -Pzo '(?s)START.*?bar.*?END' file.txt   The problem is, that this expression is greedy and prints out:  START      # starts at first "START"-tag, not the next one test1      # test2      # foo        # END        # some       # more text  #  START test3 bar test4 test5 END   It's not done with the grep flags --before-context / --after-context, because the count of lines before and after can differ.  The tool used by text-processing doesn't matter. It should work on a general RedHat system. Also the faster the tool grabs the lines, the better it will be. Because I have big logfiles of each about 150MB.  Can someone tell me, how to achieve my goal the best way?    Update:  Okay, I got it. I just had to think about how to construct my command from don_crisstis link. Here's the solution:  ed -s file.txt <<< $'g/bar/?START?,/END/p\nq\n'   Thank you very much for all your very fast help!  And yes, finally it's a duplicate...

I have this file:  sometext1{ string1 }  sometext2{ string2 string3 }  sometext3{ string4 string5 string6 }   I want to search this file for a specific string and print everything before this string up to the opening { and everything after this string up to the closing }. I tried to achieve this with sed but if I try to print everything in the range /{/,/string2/ for example sed prints this:  sometext1{ string1 }  sometext2{ string2 sometext3{ string4 string5 string6 }   If I search for the string "string2" I need the output to be:   sometext2{ string2 string3 }   Thanks.


This question has not been asked before.  That link above is no help.  When trying to pass TXTurl variable in URL everything after the hashtag does not pass as the variable because it is a fragment.  I was doing some reading, and it the variable does pass as %23.  I have been trying to change the # to a %23 before it goes into the database.    I have tried urldecode() urlencode() - I have tried the below myUrlEncode function I found.  function myUrlEncode($TXTurl) {     $entities = array('%21', '%2A', '%27', '%28', '%29', '%3B', '%3A', '%40', '%26', '%3D', '%2B', '%24', '%2C', '%2F', '%3F', '%25', '%23', '%5B', '%5D');     $replacements = array('!', '*', "'", "(", ")", ";", ":", "@", "&", "=", "+", "$", ",", "/", "?", "%", "#", "[", "]");     return str_replace($entities, $replacements, urlencode($TXTurl)); }   try {     $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);     // set the PDO error mode to exception     $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);      // prepare sql and bind parameters     $stmt = $conn->prepare("INSERT IGNORE INTO MyFAQlist (TXTurl, TXTlinkname)      VALUES (:TXTurl, :TXTlinkname)");     $stmt->bindParam(':TXTurl', $TXTurl);     $stmt->bindParam(':TXTlinkname', $TXTlinkname);     myUrlEncode($TXTurl);       // insert a row      $TXTurl = "$TXTurl";     // insert a row     $TXTlinkname = "$TXTlinkname";     $stmt->execute();   I want to replace # with %23 when inserting TXTurl into database.  Also Tried to use rawurlencode. ddint' work  $stmt = $conn->prepare("INSERT IGNORE INTO MyFAQlist (TXTurl, TXTlinkname)  VALUES (:TXTurl, :TXTlinkname)"); $stmt->bindParam(':TXTurl', $TXTurl); $stmt->bindParam(':TXTlinkname', $TXTlinkname); $TXTurl = rawurlencode($TXTurl);

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


What does "as good a film as the Coen brothers...have ever made" mean?  Does it mean  that the film is their best? what is the underlying structure?

Nosey Flynn was sitting up in his usual corner of Davy Byrne's and,   when he heard the story, he stood Farrington a half-one, saying it   was as (1) smart a thing as (2) ever (3) he heard. (James   Joyce, Dubliners)   The meanings of the (1), (2), and (3) seem like:  (1) as : “to the same degree or amount” () : this meaning requires “indirect complement (’s term)”, i.e. as ever ~. (2) as : “used to make comparisons” () : in “as A as ever B,” A has equal importance as ever B. (3) ever : “used as an intensive” () : the best  so, I suspect the highlighted part means: ‘it was as smart a thing as the smartest ones he’d heard.’ Is that a way to understand the construction?


How do you declare a variable as global once it has been created inside a function? This is my example code (not what it is being used for): def function():     pancakes = input("pancakes input")     pancakes = global(pancakes) #i don't know how to do this part  def function2(pancakes):     print(pancakes)      function() function2(pancakes)  By the way I know that returning the variable also works but it will not with my program.

How can I create or use a global variable in a function?  If I create a global variable in one function, how can I use that global variable in another function? Do I need to store the global variable in a local variable of the function which needs its access?


I know the Formula V=IR.  Many years ago I  had a sony walkman.  This unit ran on 2AA batteries and the label said it used 200ma.  I wanted to hook it up to my car.  12VDC I attempted to build something to do this.  Using resistors, and only resistors,  1/4 Watt resistors I put in 60 ohms, and hooked the thing up.  I estimate that the resistor got up to the temperature of about 500 degrees.  The resistor was so hot it would start fires! I went to Radio Shack and bought something that worked 1 week later.  The device appeared to have a transformer (size of dime), capacitors, and resistors.  It got warm about 80 degrees. What did I do wrong in my circuit design?  Why would something like this need capacitors? I asked my father and he told me that the 9Volts from 12V to 3V has to be converted to heat.  It never made seance to me. Note:  I did this over 25 years ago and it still bothers me that I do not understand this basic concept.  I was making 2.11 per hour, and spending 30 bucks was a big deal.

When would you use a voltage regulator vs a resistor voltage divider?  Are there any uses for which a resistor divider is particularly bad?


I have two wooden blocks, one facing up and one facing the side as you can see in the image, I do not want the block to be vertical, I want it to be horizontal when I give the command //set <block>  Does the //set <block> command have more than one argument to do this? Or is there another command to rotate an already placed block?  The command I am using is this: //set 17:1   The server version is 1.5.2, so the WorldEdit plugin version is 5.5.6

What command should I use to rotate wood to S,N,W,E,D and U?  I read the entire world edit guide and tried some things but all the results are not satisfactory.


I have a paragraph starting with the below sentence. "it" is not referring to any specific noun. Is there any problem with that?  It  has been estimated that health care costs accounted for 11.6% of Canada’s GDP in 2019, the majority of which were spent in hospitals.  Best, Amir

I am very confused. Unless I am mistaken, I know "it" has to be a noun of some sort, but I am unable to figure out what noun "it" is referring to.   What is "it" in the following sentence:      It is clear that Bob likes doughnuts.   Heres another couple of examples:     It is impossible to fly.


The series involves two groups of aliens who have been fighting an interstellar war for many years before the first book.  The war is started by a race of jellyfish-like telepaths who have used their powers to control several species which they use as soldiers.  The jellyfish aliens have declared a holy war against all sapient vertebrates.  The only species on their side that aren't being actively controlled through their telepathy are invertebrate species who have joined the holy war.  In this series, humans are immune to telepathy--what's more, a completely unconscious reflex tends to destroy the mind of anything even attempting to affect their minds.  One of the central themes of the series is how well suited humanity is to warfare, and all the sacrifices forced on humanity as they become nothing but soldiers fighting against the jellyfish, losing almost all culture not in some way related to being soldiers, as the other races in their alliance take over the other roles.  Other species I recall include a bird race that is gifted at linguistics but can be sent into shock by even seeing a low quality recording of a human walking around a room.  They just cannot handle the hide or flee reflexes triggered by seeing such an obvious predator.  Another race is a crab like group that is so antisocial they all keep suicide buttons at hand when working with other races, and only work to help the human alliance's side because the jellyfish won't leave them alone.  There is a race that bears a faint resemblance to large rats who were previously the best soldiers on their side, and another renowned for their intellect.

I recall there were two warring alien empires, one of which was led by a race that could telepathically inflict pain on others, but when they tried to do it to humans, it would backfire. something about human's animal instincts being much closer to the surface than the other species.  Humans made the most aggressive and dangerous fighters, so both empires tried to reruit humanity, since the other races involved in the war were fairly monolithic and sided all with one empire or the other. Humanity was all splintered though.  The empire led by the telepathic race claimed that everyone in it was equal but in reality the telepathic race was in charge.


I want to know whether there is a way to tell who views my Timeline/Profile/pics on Facebook if we aren't friends.  Is there an app or a log or something?

Is there any way we can know who viewed our profile recently on Facebook?  I remember Friendster had (has?) this function, but I'm not sure whether Facebook does.


I want to install panda via terminal. I tried  sudo pip install panda    But it shows the error below:   sudo: pip: command not found

I have installed numpy and pandas using pip. After executing my python code it shows the following error:  Traceback (most recent call last):   File "demo.py", line 1, in <module>     import numpy as np   File "/home/tauhid/.local/lib/python3.6/site-packages/numpy/__init__.py", line 142, in <module>     from . import core   File "/home/tauhid/.local/lib/python3.6/site-packages/numpy/core/__init__.py", line 59, in <module>     from . import numeric   File "/home/tauhid/.local/lib/python3.6/site-packages/numpy/core/numeric.py", line 3093, in <module>     from . import fromnumeric   File "/home/tauhid/.local/lib/python3.6/site-packages/numpy/core/fromnumeric.py", line 17, in <module>     from . import _methods   File "/home/tauhid/.local/lib/python3.6/site-packages/numpy/core/_methods.py", line 158, in <module>     _NDARRAY_ARRAY_FUNCTION = mu.ndarray.__array_function__ AttributeError: type object 'numpy.ndarray' has no attribute '__array_function__'   I have tried uninstalling and reinstalling the packages, but same error reoccurs.


If I have multiple constructors in a class, how do I avoid duplicate code for those fields which are initialized identically for all constructors, or is this not preferable?  For example:  class ComparableThing<K extends Comparable<K>> {   private int someField;   private Comparator<K> comparator;    public ComparableThing() {     this.someField = 0;     this.comparator = Comparator.naturalOrder();   }    public ComparableThing(Comparator<K> comp) {     this.someField = 0;     this.comparator = comp;   } }   Is there a way to avoid the duplicate code in initializing someField, or is this duplicate code considered acceptable/preferable?

Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? And what could be the best way to call another constructor (if there are several ways to do it)?


I'm trying to compare a value from a cell in a JTable and a value returned from an SQL ResultSet, but it always return FALSE even if I know they are equal.  Their content equals "1" I also checked for the length of each string which is 1.      boolean test = (myJTable.getValueAt(0, 0).toString() == rs.getString("ID"))     //test equals to false.   What makes them different??  Thank you in advance for your help.

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?


Context: I am a Romanian who wants to make a "Eurotrip" this summer. To make the situation a bit simple, I am referring to motorway traffic only.  The Romanian law makes a clear difference between overtaking and passing.  In Romania, you can overtake on the left lane only, but you can pass on all lanes.  Overtaking (is the same as in The US and all the countries of the EU): signal left, change lane, move in front.  Passing (as being described by the Romanian legislation): you cruise on the motorway and you encounter a vehicle on your left or right lane moving slower than you and you simply keep your lane and pass him.  The difference between passing and overtaking is that when you overtake you move from one lane to another and the distance to the vehicle in front of you is smaller than 100m. When you change lanes and the distance between cars is bigger than 100m you legally execute the change lane maneuver. After you execute a change lane maneuver, you encounter a vehicle moving slower than you on your left or right lane and you cruise along him, you would be executing the passing maneuver, NOT overtaking.  The situation described  is perfectly legal in Romania.  I know for sure that in Germany passing is the same as overtaking, so you can't pass on the right lane.  My question is what other countries in EU, or around the globe, make this difference between overtaking and passing and legally allow you to cruise along slower vehicles on all lanes, not only the left lane?

I've got a question about how to drive the car in Europe on Highways. In the US, I can overtake another car on either side, and I am fine.  In Europe I was told that I have to drive on the right side (Germany), and to overtake on the left side of the other driver.  Now I had following situation, and I did not know how to handle this properly: I was driving along on the right lane, the Autobahn was 3 lanes wide on my side, and was going around 110 km/h. Someone overtook me, but he stayed on the middle lane, and suddenly got slower. He wasn't really in front of me, so I could not change to the left lane, but I was told I may not overtake on the right side.  Would I have to brake in such a situation, or should I just ignore it, and overtake him again on the right side?  (I overtook him, and he was on the phone, so I guess that was why he got distracted and slowed down that much).


Is there any section cut addon. In sketchup there is option we can cut the section mean time or show inner render parts.   This is the  of sketchup how it works and what i need. Is there any addon or how can i make a section view in Blender.

I'm trying to create animated  on multiple objects in my scene. For example, in my car model, the seats and other interior objects are separate objects.    talks about using an animated bisecting technique. However, it involves adding a solidify and boolean modifier to every object.  Is there an easier solution?


Is there any formal salutation to greet someone when you meet them at night? A prefix such as 'Good' with morning, afternoon and evening works well but implies altogether a diferent meaning when used with night. To be specific, what can be prefixed with night here or any better way of 'greeting' will also work. P. S:-Informal greetings like hello and hi won't work here.

Possible Duplicate:          I am in the process of creating a software application which displays a greeting to users based on the time of day. I have come to a blank on what to display to the user when it is late at night. 'Good night, [user's name]' just doesn't seem right.  So, what is an appropriate greeting to use at night time?


I have vivid 15.04. I tries the comments how to update and upgrade from the EOL versions such as vivid. I still get 404 error for repositories. I deactivatd PPAs , still the same problem. I get "fail to update repository information check your internet"?

I am currently using Ubuntu 10.04. I know there is a 10.10 release, but can I upgrade directly to 11.04? Could you walk me through the steps please?


Why does the Newton-Raphson method for solving equations always work?   What I know:   I know that if $f(x) = 0$, then the Newton-Raphson method may be applied. It states that $$x_{n+1}=x_n-\frac{f(x_n)}{f'(x_n)}$$ where the solution to $f(x) = 0$ is $x_\infty$ I also know that you can select a point on the graph of $f(x)$ (your first estimate $x_1$), and Newton-Raphson takes the gradient of that point, and where that gradient meets the $x$-axis, and the x value is where $x_2$ is.      I know how it works, but why the $$\frac{f(x)}{f'(x)} ?$$  It seems that the curve is divided by the gradient, but what does this give?   I would just like an explanation of why this works.

Before I am told, I want to clarify that I searched first, and I don't believe this to be a repost. I understand the formula in terms of how to apply it, and I've seen graphical representations and everything. I get that we are finding where the tangent line has a root, then choosing a new $f(x)$ at that point and finding the root of its tangent line, effectively closing the distance between x and the root r.   What I do not understand, is what $\frac{f(x)}{f'(x)}$ is actually doing. I know it can be used to find the root x, as it is derived from $y=mx+b$, but how is dividing $f(x)$ by its derivative getting me the root? Why does this work? My intuition is telling me (before I actually tried it) that I was getting some y value, then seeing how many times the slope goes into it; but this would give me the $x$ coordinate, wouldn't it? I can use it, but it's not clicking as to why, and I'd like to fix that so I can actually understand what is going on.


I am new to PyQGIS. I have a Geodatabase that contains feature classes. I am trying to get those feature classes into PyQGIS but how do I loop a Geodatabase?

I can access ESRI .GDB data using OSGeo's OGR. The following code gives feature class names embedded in .GDB...  from osgeo import ogr  driver = ogr.GetDriverByName("FileGDB") data = driver.Open(r"D:\pycharm_development\turkiye_db.gdb", 0)  feature_class_list = []  for i in data:     foo = i.GetName()     feature_class_list.append(foo)     feature_class_list.sort()  print feature_class_list   But I cannot access ESRI .GDB data in PyQGIS environment, unfortunately. PyQGIS works properly in my PC and .SHP files can be loaded successfully...  Is QgsVectorLayer() approach true or should QgsDataSourceURI() class be used to handle that?  P.S. I installed from OSGeo4W 64-bit installer. I'm using PyCharm IDE.


I currently run Ubuntu 20.04 Desktop server. And I am using the SFTP function by installing OpenSSH on the server. For testing purposes, I temporarily created a directory called /home/mydirectory/storage, where I created subfolders, each of which had folder-name privileges. For example I have named A,B,C folders and each A,B,C folders has A,B,C groups privilege. And I expected that if A group person has access to /home/mydirectory/storage folder with SFTP client, it should only show A folder. And also the B, C folder should be hidden and cannot access. But the current situation shows A,B,C all folders and cannot access to B,C folder. How can I hide the B,C folder?

I'm setting up ACL permissions in CENTOS.  I'm getting close to the structure that I have in mind however one piece is missing for completing the puzzle.  Is there any way to HIDE a file/directory from a specific user/group?  I'm not talking about not being able to read, change dir to it. I want to completely hide it from the specific user/group (not to show up on ls -la).


It seems common for MacBookPros2018 overheating when connected to external display (see other info about the general problem , or ).  Despite there is no risk for HW, it's quite uncomfortable for who works on them.  I noticed that if I connect my MBP to an external display when it runs with battery, it does not get (so) hot.  I suppose that the MBP uses another configuration of its graphics framework when it is not connected to power adapter. Therefore, I hypothesize that if it used the same graphics configuration when it's plugged to the power, then the overheating would be reduced.  Is there a way to make the MPB use the same graphics configuration for external displays also when it is connected to the power?

I'm on a MacBook Pro (15-inch, 2018) with Mojave 10.14.1. When I connect MBP to a external displays (either via HDMI or via Thunderbolt 2 adapters), the temperature raises sensibly (i.e., CPU temperature lies constantly over 90°) and fans start running fast (i.e., more than 50%) frequently, even if I am doing very simple tasks (e.g., writing in Word with a couple of Chrome tabs open with stackoverflow).  I'm not sure that the problem started with Mojave or if it isn't actually related to the OS version.  I'm wondering if there is a way to limit this annoying overheating as well as fans activity, while using external monitors.


I would like to check if the input has any character in it, then I sould add an active class to it and when it's empty then I should remove the active class. It's working only if the input only has the active class. Could you help me to improve my code to be able to remove ONLY the active class even if it has more?
     <input type="text" id="lastname" onblur="checkInput(this)" />     Lastname

     <input type="text" id="invalid" class="invalid" onblur="checkInput(this)" />     Firstname

How can I change the class of an HTML element in response to an onclick or any other events using JavaScript?


I am  an  almost layman  in  physics,  and  don't  know much in math (only basic  knowledge  upto  trig ), and want  to  learn physics . .  As  I am  completely inexperienced, and considering most  of  the  textbook  in  physics  are  Hallday  Resnic styled  plug  and chug, somewhere  I found  the  suggestion  to  struggle with Feynman. Crazily most  of  the  places  suggested you  would go astray with  Feynman  (I went astray,  It took  me  two  weeks to  partially understand the Gravitational  Energy, probably fourth chapter) unless you  have  a good  intuitive grasp of basic  ideas  in  physics.   Are there  any  good (not pop sci)  introductory physics books? I'm willing  to struggle to get good understanding,  and (there is no cramming exam pressure to rush) and the book should must be fun and  interesting*.    Measurement by Paul Lockhart is  an excellent  example of  such  book,  but  it  is  in  mathematics - I want in physics.

Every once in a while, we get a question asking for a book or other educational reference on a particular topic at a particular level. This is a meta-question that collects all those links together. If you're looking for book recommendations, this is probably the place to start.  All the questions linked below, as well as others which deal with more specialized books, can be found under the tag  (formerly ).  If you have a question to add, please edit it in. However, make sure of a few things first:   The question should be tagged  It should be of the form "What are good books to learn/study [subject] at [level]?" It shouldn't duplicate a topic and level that's already on the list   Related Meta:


I am trying to create an array of an object inside a class. Unfortunately I am keep running into nullpointerexception. This is my code, what could be wrong?    /////Init Buttons/////     //      button[] Buttons=new button[nButtons];    for (int i=0; i<nButtons-1; i++)       Buttons[i]=new button();     /////End/////       /////Set Button information/////       for (int n=0; index < nButtons*4-1; index+=4, n++) {        ////////       if (debug)         print("Index ");         println(index);         print("N ");         println(n);       ////////           String[] pieces = split(lines[0], ' ');        ////////       if (debug)       {         print("Button name ");         println(pieces[index]);         print("Button X ");         println(pieces[index+1]);         print("Button Y ") ;         println(pieces[index+2]);         print("Button size ");         println(pieces[index+3]);       }       ///////        Buttons[n].setInfo(pieces[index], Float.parseFloat(pieces[index+1]), Float.parseFloat(pieces[index+2]), Float.parseFloat(pieces[index+3]));     }

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


My background is not in stats but I did do some in school. You're help is really appreciated.  I'm wondering what is the best way to find some correlation between a binary variable and a discrete variable with a range between 1 and 5 (inclusive).  For example, let's say the binary variable is whether an employee was working at a lemonade stand at a specific time.  The discrete variable ranges from 1 to 5 and equates to how a customer rated the lemonade at a specific time.  Data example:  Time  | Rating | Bill Worked? | Susy Worked?  10:00 |   5    |       0      |       1  10:35 | 3 | 1 | 0  etc.  I'd like to see if certain employees impact the rating of the lemonade by a significant amount.  Not even sure if correlation is the best way to do this...  Thanks very much in advance!  Edit: The distribution of the "customer rating" appears to be lognormal...  1: 300  2: 70 3: 330 4: 1100 5: 3000  I ran a linear regression but I'm worried that the results will be insignificant.

There are two Boolean vectors, which contain 0 and 1 only. If I calculate the Pearson or Spearman correlation, are they meaningful or reasonable?


I added one conflicting repository by   sudo add-apt-repository ppa:obsproject/obs-studio   and now I would like to remove the repository in my Debian 8.1.  I cannot find it in /etc/apt/sources.list.   How can you remove the repository in Debian 8.1?

I run   sudo add-apt-repository ppa:noobslab/indicators   to install my-weather-indicator but it requires GTK3 and I don't want to proceed.  So I'd like to undo that command. I'd checked my /etc/apt/source.list but I didn't find any line related to it.   What should I do now?


A folder (not the disk itself) containing misc. things in my flash drive turned into a single USBC[]ÇNY file when I was running the Sublime Text app. It has no modified-date, nothing, looks like something corrupted and the file manager says it's both 3.42 GB and 0 GB large.  My question is now how can that happen? I rant disk-check (dskchk) and a tool like Recuva and yet nothing got back. The best I got is, thanks to dskchk, disrupt that file, but it just had a USBC... header with most content nulled, and were just 32 KB., meaning it had nothing! How could I at least avoid that to happen?    Before I tried dskchk and Recuva, I used WinRaR to open the USBC file and it said the file doesn't exist. I've tried renaming it too and it were still n't existing. Only the command prompt found it:    Yet more, that _Self folder just had a ascargo folder. That ascargo folder was open in Sublime Text (a workspace), so maybe that could be the issue?  Now I doubt I can really recover the content, but lucky it was just an experiment... I'd like to know how that happens.

I have a USB flash drive which is no longer recognized by my computer. Windows Disk Management and DiskPart report No Media with no storage space (0 bytes) on the drive and I cannot partition or format the drive:     If the drive appears in Windows Explorer, trying to access it returns an error message indicating that there is no disk inserted, such as the following:     Please insert a disk into drive X:.   Various disk partitioning and data recovery utilities don't recognize the drive or only give a generic name for the drive and cannot access the contents of the drive.  What can I do? How do I recover data from the drive?     This question comes up often and the answers are usually the same. This post is meant to provide a definitive, canonical answer for this problem. Feel free to edit the answer to add additional details.


I have a problem getting a correct/accurate string representation of float/double/long double values.  I have this function that attempts to get a string representation of a floating point value:  template <typename T> std::string double_to_string(const T& v) {   static_assert(std::is_floating_point<T>::value,                 "T is not a floating point type");   std::stringstream sstr;   sstr.setf(std::ios::fixed | std::ios::showpoint);   sstr << v << std::ends;   return sstr.str(); }   I invoke it with float, double and long double values, but do not get a correct/accurate string representation of the actual value I pass in to the function:  // float: std::cout << double_to_string(77777777777777.7777777f) << std::endl; // double: std::cout << double_to_string(77777777777777.7777777) << std::endl; // long double: std::cout << double_to_string(77777777777777.7777777L) << std::endl;   The output I get is as below:  // float:  77777780867072.000000  // double: 77777777777777.781250  // long double: 77777777777777.777779   Is there any way I can get an accurate string representation of float/double/long double values in C++?  (p.s. I'm using g++ 7.2.0)  Thanks.

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


In theoretical physics, the  refers to the discovery made in 1968 by Italian theoretical physicist Gabriele Veneziano that the Euler beta function, when interpreted as a scattering amplitude, has many of the features needed to explain the physical properties of strongly interacting mesons  Is Veneziano amplitude able to explain the physical properties of strongly interacting s (Proton, Neutron...)?

The  claims that the  can be interpretted as a scattering amplitude. Why is this?  In another word, when the  Euler beta function is interpreted as a scattering amplitude, what features does it have that make it able to explain strong force of ?  What properties of (or why) the Euler beta function (when interpreted as scattering amplitude) has string behavior?


Given the following cruise scenario, how many days would be counted again a Schengen 90 day count? DAY 1   Southampton UK DAY 2   At Sea DAY 3   Kirkwall, Orkney Islands (UK) DAY 4   Tórshavn Faroe Islands (Denmark protectorate) DAY 5   At Sea DAY 6   Akureyri (Iceland) DAY 7   Isafjörður (Iceland) DAY 8-9 Reykjavik (Iceland) overnight DAY 10-12   At Sea DAY 13  Honningsvåg, Norway DAY 14  Tromsø, Norway DAY 15  Leknes, Lofoten Island (Norway) DAY 16  Narvik (Norway) DAY 17  At Sea DAY 18  Trondheim (Norway) DAY 19  Kristiansund (Norway) DAY 20  Alesund (Norway) DAY 21  Skjolden (Norway) DAY 22-23   At Sea DAY 24  Southampton (UK) I am expecting every day from day 4 through day 21, i.e. first Schengen port to last, but if this can be confirmed I'd be most appreicative as we try to count the days for multiple vacations.

I am planning on spending 90 days in Schengen zone countries.  I will be taking a cruise between Lisbon and Barcelona.  Do the days at sea count against the 90 days allowed for staying in the Schengen zone?


I decided to make an experiment. I created two hash maps in Java. One hash map with 100 entries and a second hash map with 10000000 entries.  public class MainJava {  private static int NUMBER_OF_ITERATIONS = 1000000; private static int SMALL_MAP_SIZE = 100; private static int BIG_MAP_SIZE = 10000000;  public static void main(String[] args) {     Map<Integer, String> smallMap = createSmallHashMap();     long start = System.currentTimeMillis();     for (int i = 0; i < NUMBER_OF_ITERATIONS; i++) {         smallMap.get(i % SMALL_MAP_SIZE);     }     long end = System.currentTimeMillis();     System.out.println("small: " + (end - start));      Map<Integer, String> bigMap = createBigHashMap();     start = System.currentTimeMillis();     for (int i = 0; i < NUMBER_OF_ITERATIONS; i++) {         bigMap.get(i % BIG_MAP_SIZE);     }     end = System.currentTimeMillis();     System.out.println("big: " + (end - start)); }  private static Map<Integer, String> createSmallHashMap() {     Map<Integer, String> smallMap = new HashMap<>();     for (int i = 0; i < SMALL_MAP_SIZE; i++) {         smallMap.put(i, "small-map" + i);     }     return smallMap; }  private static Map<Integer, String> createBigHashMap() {     Map<Integer, String> bigMap = new HashMap<>();     for (int i = 0; i < BIG_MAP_SIZE; i++) {         bigMap.put(i, "big-map" + i);     }     return bigMap; }   }  I retrieved values from both hashmaps and measured the time it took in both cases. I ran the code several and saw that the time to retrieve values from the big hashmap was almost ALWAYS longer than the small hashmap.   How is it possible? Retrieval time complexity of a hash map is 0(1). I'd expect similar time values for both maps.

How do you write (and run) a correct micro-benchmark in Java?  I'm looking for some code samples and comments illustrating various things to think about.  Example: Should the benchmark measure time/iteration or iterations/time, and why?  Related:


public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.beta);      ed_code = (EditText) findViewById(R.id.et_beta_01);     bu_ok = (Button) findViewById(R.id.bu_beta);      bu_ok.setOnClickListener(new OnClickListener() {             @Override         public void onClick(View v) {                 // TODO Auto-generated method stub             String code = ed_code.getText().toString();             String target = "vsi8";              Log.v(TAG, code+"="+target);              if(code == target){                     Intent intent = new Intent(BetaCheck.this, AppMenu.class);                 startActivity(intent);             }             else {                     Toast.makeText(getApplicationContext(), "wrong", Toast.LENGTH_SHORT).show();                     ed_code.setText("");             }         }     }); }   It seems that the the if statement does not understand that the 2 values are equal.  Thanks for the help

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?


I have downloaded python 2.7 installer. After downloading the installer, I executed the following command in the terminal: /home/najam/Downloads/Anaconda2-4.2.0-Linux-x86_64.sh The execution resulted in the following error: bash: /home/najam/Downloads/Anaconda2-4.2.0-Linux-x86_64.sh: Permission denied    What am I doing wrong? It'll be much helpful if step-by-step sequence of commands is posted for Anaconda's installation. Thanks.

How to install  on Ubuntu?   Is there a way to use apt-get install?   I only have command line access to my server. How do I install Anaconda on Ubuntu 14.04 from the command line?


I'm searching for a solution to capture my desktop and output it as a live stream for clients in a local network. I already tried ffmpeg and VLC, but the results were that it was not a live-stream.  It became a kind of recording that always started from the beginning when trying to watch.  I'm trying my luck now with WebcamStudio, but I haven't had any success yet.  Does anyone know a solution for my problem?

I wish to execute a video in my PC and stream it in the LAN so anybody can connect to it and watch it. What steps do I need to do to accomplish this in an easy manner.


This cartoon is animated and not in CGI or old animation like the 90s. I think it was made in 2009-2014 by Cartoon Network or Kix. The only things I know is that the cartoon involves a group of 3 people who have magical powers (the team consist of 2 boys and 1 girl and an orange alien with an antenna). One of the boys has blond hair and white and the girl is dark-skinned. They go around fighting rival teams with their magic and in the second fight they turn into the magical creatures they gained their powers from. I remember the blond character saying "freeze ray- what the, freeze ray is a blue attack not a green attack" and the girl character says "you can't hit what you can't see- ha missed". I remember the orange alien saying "don't eat me- I'm sweaty and my antenna is chewy". I remember the characters saying the name of the creature and rising up into the air with the image of the creatures behind them (this is in the first fights they do and in the second fights they turn into their creatures) The orange alien character can use this "magic" as well but he only does it for one or two episodes (one of the rival team characters who is female turns into a spider during their fights).

Looking for a show about a group of three kids/teens who, using cards to change into monsters, fight and recover relics. I believe there are two or three other groups of three also trying to get the relics.  In the main group there are two boys and a girl. The boys were both white, one is from a farm and I don't know where the other is from. The girl was dark skinned and either black or blue hair. The three travelled around the world using a red plane.  I think they only use one monster primarily. The girl uses a monster created from gas and at one point is green. One of the boys uses a metal robot most of the time and at one point is given another better version of that card to use. I believe the episode for this was called something like green with envy.  All I'm getting from the internet is that it may be Chaotic, but that isn't the right show.  I also believe the girl's name was Mai and one of the boys were Ky, but I may be wrong.


I have installed wordpress in localhost and now trying to install a jQuery-slider-plugin to it. But when I try to install the plugin, it prompts me to enter the ftp details. Is there any solution to install the wordpress plugins without providing the ftp details? Thanks in advance...

I am using  on my live server which only uses  using an  key.    I want to install and upgrade plugins, but it appears that you are required to enter your FTP login to install the plugins. Is there a way to install and upgrade plugins by manually uploading the files instead of having WordPress handle the entire process?


I want to upgrade my laptop's RAM but I doubt wether the combination will work. Are there any risks of damage?  Here are the specifications of my laptop:   Processor         : Core i3 M380 @ 2.53 GHz Ram Installed     : 2 GB DDR3 532.1 MHz, CL7. Operating System  : Windows-7 Ultimate (64-bit)   The RAM I want to install: 4 GB DDR3 1333 MHz CL9.  If it works will I get 6 gigabytes of RAM?

I have two PC3200U modules and two PC2700 DDR modules. My mainboard supports both types and has 4 slots which are each color coded. So if I put each pair in the slots of the same color I'm good right? Would there be a performance increase if I used the exact same RAM modules like 4x PC3200 or 4x PC2700?


I am trying to understand an elementary idea in the transpose of a linear operator, namely that if $S \in L_K(U,V)$ and $T \in L_K(V,W)$ for vector spaces $U,V,W$ over a field $K$ that   $(S \circ T)^t = T^t \circ S^t$.   So it seems I should first take a linear form say $g:W^* \rightarrow U^*$ then $(S \circ T)^t (g) = g(S \circ T)$. Here is where I am stuck. Any hints/tips appreciated.

Let $T : V \longrightarrow W$ and $U : W \longrightarrow Z$ be linear maps. How do I prove that $(U\circ T)^{*} = T^{*}\circ U^{*}$? I'm used to seeing $V^{*}$ not $(U\circ T)^{*}$. Any help is appreciated.  $^{*}$ denotes the dual map (transpose).


For many months the Review Queue list at the  had been showing me the "Low Quality Posts" as very busy (with the red dot), but when I visit the queue, the list is empty.     It's been  at the Portuguese Meta that the queue indeed has posts, but probably only ones on which I have already voted, so they aren't visible to me any more. The latter is expected behavior, but then the queue list shouldn't show itself as busy either - I consider that a bug (or at least ill-adjusted thresholds).  I know the system , but right now it's really only getting people to ignore the queue completely.  Update: right now it's back to normal, after a local mod emptied the queue. This probably means it's not a solution, just a temporary respite.

I just noticed that the Close Votes review-needed indicator is red for me on ELL:    When I click on it, however, it shows that the queue has been cleared:    I've read the explanation about how the review-needed indicators work, but I didn't see anything that could explain what's happening:    I've tried refreshing the page in Firefox, and I've tried loading the page in Chrome, all with the same results.  Any idea what's going on?


I have a table cell with a text and icon:    .icon {   float: right;   margin-right: 5px; }         Some text         	     Chrome displays them vertically aligned to each other, Firefox display the text on the upper left and icon lower right corner.  How can I fix that, thanks!!

I have a div with two images and an h1. All of them need to be vertically aligned within the div, next to each other. One of the images needs to be absolute positioned within the div. What is the CSS needed for this to work on all common browsers?

testing...


I am new to the world of linux and I've installed a Xubuntu 12.04 on my desktop computer. I am learning web development (Php, html, CSS, javaScript, JQuery etc...) so I need to establish an Apache server on my machine. With synaptic package manager I already installed some packages that seem to work so when I type localhost to my browser it gives an html site that says:   "It works! This is the default web page for this server. The web server software is running but no content has been added, yet."  I have read a few things on the internet on this topic, and now I know that I should be able to write my php in documents that are stored in filesystem/var/www/ but I cannot create documents in there - apparently because I am not logged in as root. Could somebody help me with that?   Also please note that I have very little (if any at all) knowledge of linux so please make it comprehesnible for such an uninitiated user as I am.

I want to stop having to use sudo everytime I work in /var/www. How can I do that? I simply want to put all of my sites into this directory and work with them without too much pain.


Is there an easy way to write a generator to generate all lists that are k elements long, where each element ranges from 1 to n?  So if k=3 and n=3, it would generate  [1,1,1] [1,1,2] [1,1,3] [1,2,1] [1,2,2] [1,2,3] [1,3,1] ... [3,3,1] [3,3,2] [3,3,3]

How can I get the Cartesian product (every possible combination of values) from a group of lists?  Input:   somelists = [    [1, 2, 3],    ['a', 'b'],    [4, 5] ]   Desired output:  [(1, 'a', 4), (1, 'a', 5), (1, 'b', 4), (1, 'b', 5), (2, 'a', 4), (2, 'a', 5) ...]


I am trying to understand some code I found which reads command line arguments (attached below). My concern is what purpose of the "if __name__ == __main__"line is...  Why would I use that line instead of just using the code below, main(sys.argv[1:]). What extra use does it provide?  import sys, getopt  def main(argv):    inputfile = ''    outputfile = ''    try:       opts, args = getopt.getopt(argv,"hi:o:",["ifile=","ofile="])    except getopt.GetoptError:       print 'test.py -i <inputfile> -o <outputfile>'       sys.exit(2)    for opt, arg in opts:       if opt == '-h':          print 'test.py -i <inputfile> -o <outputfile>'          sys.exit()       elif opt in ("-i", "--ifile"):          inputfile = arg       elif opt in ("-o", "--ofile"):          outputfile = arg    print 'Input file is "', inputfile    print 'Output file is "', outputfile  if __name__ == "__main__":    main(sys.argv[1:])

Given the following code, what does the if __name__ == "__main__": do?  # Threading example import time, thread  def myfunction(string, sleeptime, lock, *args):     while True:         lock.acquire()         time.sleep(sleeptime)         lock.release()         time.sleep(sleeptime)  if __name__ == "__main__":     lock = thread.allocate_lock()     thread.start_new_thread(myfunction, ("Thread #: 1", 2, lock))     thread.start_new_thread(myfunction, ("Thread #: 2", 2, lock))


I want to install printer Cannon I-Sensys MF212W on Ubuntu can anyone help me, please

I tried to install the MP190 drivers, but appeared a message show me that requires to have libcupsys2. I understand that libcup2 is an update of libcupsys2.   How do I solve this? Are there proprietary drivers for my Canon printer or scanner?


Nautilus doesn't show up in the Alt + Tab program icons although I have it open.  You can see Nautilus open in the back and it doesn't show up in the tab.    What happened? How can I fix it?

When I press alt+tab to change between windows, the  "Files" window doesn't appear. It's really annoying because when I try to access the previously opened "Files" window, I have to minimize everything or open another "Files" process so I end the day with a lot of opened "Files" instances.


I know that words like  cuppa, fella, attaboy and attagirl  are contractions of, respectively,  cup of tea, fellow, that's the/a boy and that's the/a girl.  I wonder if there is a term which would describe the process through which the orthography of these contracted words changed to what they call  (writing words as they are pronounced). For example, the British  comes from cup of tea but it renders just cup of. As for attaboy, it comes from , but there were stages ("That's the boy"—"'at's a boy"—"atta boy" – there is even a variant of at her, boy!) Also, cuz just popped into my mind because (!) it became so short. Kinda seems to be kind of (!) in between. So from a proper English orthography there is a shift towards phonemic orthography in informal English. Is there a term for this? Does anyone know of any reliable investigations of this process? Edit: The question indicated as already existing does shed some light, but the accepted answer is relaxed pronunciation. And the question seems to focus on speech and pronunciation. My question is rather about this tendency to write in this way in informal writing. It may be though that such term does not exist in orthography. The result is phonemic orthography; just wondered if the process leading to it has a name.

Some examples: "never" might be written as "neva" "I don't know" is sometimes written as "iono" or "I dunno" on various internet media. My question is: is there a word for this particular technique of spelling a term in the way it is (sometimes) pronounced?


On many, many occasions in Skyrim, I fight an enemy and get them to low health. At this point, by far the most common thing they say is:     No more! I yield! I yield!   I have, of course, learned better. But originally I figured "eh, what the hell, I've already pickpocketed him for everything, I'll let him live". As soon as he'd recovered enough to stand, he attacked me again (so I cut his head off).  Point is, are there any enemies that will actually yield when defeated (excluding Brawls), or is there really no honour among bandits?

I was fighting bandits in the sewers when one of them went into a "cower" animation, and began screaming about how he had given up.  Given that I found his terror endearing, I deigned to spare him. I tried talking to him, to no effect. Then I tried sheathing my weapon - upon which the brigand thought he had a chance, and resumed hostilities with due haste!  Sadly, he did not offer to yield again before I slew him.  And so, the question remained unanswered: do enemies actually surrender, or was this just a clever ploy to catch me with my pants down?


Do you consider the subject in the following to be compound, justifying a singular verb?  "His impact and influence is undeniable."  On the one hand, the nouns do not form a common phrase; on the other hand, they have a similar meaning so might be considered a unit. What are you views? And do you know if usage is shifting?

Can anyone tell me if I should use inspire or inspires in this phrase?     An extraordinary leader whose vision, values, integrity and boundless curiosity inspires all who follow in his footsteps.


It is the first law of thermodynamics for a very small change in the state of the system.    It is in Heat thermodynamics and statistical physics by Brij Lal, Dr. N. Subrahmanyam, and P.S. Hemne.

What is the exact use of the symbols $\partial$, $\delta$ and $\mathrm{d}$ in derivatives in physics? How are they different and when are they used? It would be nice to get that settled once and for all.  $$\frac{\partial y}{\partial x}, \frac{\delta y}{\delta x}, \frac{\mathrm{d} y}{\mathrm{d} x}$$   For what I know, $\mathrm{d}$ is used as a small infinitisemal change (and I guess the straight-up letter $\mathrm{d}$ is usual notation instead of italic $d$, simply to tell the difference from a variable). Of course we also have the big delta $\Delta$ to describe a finite (non-negligible) difference. And I have some vague idea that $\partial$ is used for partial derivatives in case of e.g. three-dimensional variables. Same goes for $\delta$, which I would have sworn was the same as $\partial$ until reading this answer on Math.SE:    Then to make the confusion total I noticed an equation like $\delta Q=\mathrm{d}U+\delta W$ and read in a physics text book that:     The fact that the amount of heat [added between two states] is dependent on the path is indicated by the symbol $\delta$...   So it seems $\delta$ means something more? The text book continues and says that:     a function [like the change in internal energy] is called a state function and its change is indicated by the symbol $\mathrm{d}$...   Here I am unsure of exactly why a $\mathrm d$ refers to a state function.   So to sum it up: down to the bone of it, what is $\delta$, $\partial$ and $\mathrm{d}$ exactly, when we are talking derivatives in physics.  Addition  Especially when reading a mathematical process on a physical equation like this procedure:  $$\delta Q=\mathrm{d}U+p\mathrm{d}V \Rightarrow\\ Q=\Delta U+\int_1^2 p \mathrm{d}V$$  It appears that $\delta$ and $\mathrm{d}$ are the same thing. An integral operation handles it the same way apparently?


I can't seem to figure this out.  Using HttpWebRequest, how do you post a form which was one of the inputs as type="file"?  Usually when posting regular fields, I do something like this:  "username={0}&password={1}", username, password"   But I don't know what to put in the type="file" field.

Is there any class, library or some piece of code which will help me to upload files with HTTPWebrequest?   Edit 2:  I do not want to upload to a WebDAV folder or something like that. I want to simulate a browser, so just like you upload your avatar to a forum or upload a file via form in a web application. Upload to a form which uses a multipart/form-data.   Edit:  WebClient is not cover my requirements, so I'm looking for a solution with HTTPWebrequest.


using Ubuntu 12.04 I got the  message in my Update manager. After trying to install I got an error-message that the Package dependencies cannot be resolved:    I tried to install libglapi-mesa-lts-trusty and the other two manually, but I aborted the install because it would have uninstalled too many things I don't know and I didn't want to risk to uninstall.  Is this a known bug? Or what else could be the reason for this error?

From yesterday my update manager gives me this message:     Your current Hardware Enablement Stack (HWE) is going out of support   on 07/08/2014.  After this date security updates for critical parts (kernel   and graphics stack) of your system will no longer be available.      For more information, please see:    But when I try to upgrade the HWE with the command suggested by hwe-support-status --verbose that is  sudo apt-get install linux-generic-lts-trusty libgl1-mesa-glx-lts-trusty xserver-xorg-lts-trusty linux-image-generic-lts-trusty   I get dependency errors:  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:  libgl1-mesa-glx-lts-trusty : Depends: libglapi-mesa-lts-trusty (= 10.1.3-0ubuntu0.1~precise1) but it is not going to be installed  xserver-xorg-lts-trusty : Recommends: xserver-xorg-input-all-lts-trusty but it is not going to be installed                            Recommends: xserver-xorg-video-all-lts-trusty but it is not going to be installed                            Recommends: x11-xserver-utils-lts-trusty but it is not going to be installed                            Conflicts: libglapi-mesa:i386 (>= 0~) E: Unable to correct problems, you have held broken packages.   How can I solve this?  I'm running Ubuntu 12.04.4 LTS 64 bit with kernel 3.5.0-53-generic.


This is my code. It fills the Date when I have this  =Updating_Date(B5) typed in C5. What it is supposed to do is fill the Date ONLY when data is present in B5, and remove the Date when No data is present. Currently it displays Date no matter what. I need to write in a condition to make it ONLY display Date when data is present in Column B.     Below is what I have typed into a module, thanks to another user, with =Updating_Date(B5) entered in C5.  Function Updating_Date(dependent_cell as Range) As Date   Updating_Date = Date End Function  Again, this displays the Date no matter if data is in column B or not.   Thanks.

I would like to have cells C5-C39 auto fill today's date whenever data is entered into cells B5-B39.  I have tried to get it to work using =TODAY() but don't how to structure the formula.