Putting background image in JFrame
Setting a background image on a JFrame using Swing
Sorting list based on values from another list How does the drift velocity of electrons in a conductor depend on the temperature? How does the drift velocity of electrons in a conductor depend on the temperature?  I have two contradicting views for this.    First, we can say that increasing the temperature of the conductor will increase the kinetic energy of the electrons. Hence, their drift velocity should increase with increase in temperature.  Or, from the relation $v_d = \frac{eE}{m}T$ ($T$ is the relaxation time) we can say that the drift velocity is directly proportional to the relaxation time. Increasing the temperature will obviously decrease the relaxation time - as collisions will become more frequent - and thus decrease the drift velocity. Hence, an increase in the temperature will cause a decrease in the drift velocity.   So which view is correct? How to Retrieve the Wi-Fi Password of a Connected Network on a Mac I need to find the password for a Wi-Fi network that I am already connected to. I'm using a MacBook Pro that's running OS X Lion. Any guidance is appreciated. I am a EE grad. student who has had one undergraduate course in real analysis (which was pretty much the only pure math course that I have ever done). I would like to do a self study of some basic functional analysis so that I can be better prepared to take a graduate course in that material in my university. I plan to do that next fall so I do have some time to work through a book fully. Could some one recommend some good books to start working on this?   Thanks in advance Permissions problems with /var/www/html and my own home directory for a website document root I'm trying to not give 777 permission in my /var/www/html folder, but I want to edit my files without sudo. So I though in create a symlink of a folder in my home directory within /var/www/html. I created it using sudo ln -sT /home/andre/www/moodle/ moodle , and the ls -la output is this:  andre@andre-270E5G:/var/www/html$ ls -la total 8 drwxr-xr-x 2 root root 4096 Mai  4 10:20 . drwxr-xr-x 4 root root 4096 Abr 29 14:29 .. lrwxrwxrwx 1 root root   23 Mai  4 10:20 moodle -&gt; /home/andre/www/moodle/   So, my moodle folder has read, write and execute permissions for everyone, and thats not what I want. I used the command sudo chmod -R 775 moodle/ trying to change it, but it stayed with read, write and execute permissions to all. I tried the same with the moodle folder in /home/andre/www/moodle, but it stayed the same. The output of ls -la in /home/andre/www/ is:  andre@andre-270E5G:~/www$ ls -la total 28 drwxrwxr-x  3 andre andre  4096 Mai  4 10:02 . drwx------ 49 andre andre 20480 Mai  4 10:01 .. drwxrwxr-x 41 andre andre  4096 Mai  4 10:02 moodle   So the folder moodle in /home/andre/www/ has the permissions I want.  As an additional problem, when I access localhost/moodle I get 403 Forbidden error.  What am I doing wrong here? How do I print all lines of a file with duplicate values in a certain column Cannot detect wireless driver intel ac wireless 9560 [logs included] Currently using Ubuntu 18.04, and my wireless driver is not being detected.  I've included a .  $ dmesg | grep iwl [    6.212724] Loading modules backported from iwlwifi [    6.212724] iwlwifi-stack-public:master:6988:0d8892f2 [    6.224583] iwlwifi 0000:00:14.3: enabling device (0000 -&gt; 0002) [    6.229811] iwlwifi 0000:00:14.3: Direct firmware load for iwl-dbg-cfg.ini failed with error -2 [    6.230540] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-39.ucode failed with error -2 [    6.230547] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-38.ucode failed with error -2 [    6.230552] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-37.ucode failed with error -2 [    6.230557] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-36.ucode failed with error -2 [    6.230562] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-35.ucode failed with error -2 [    6.236670] iwlwifi 0000:00:14.3: loaded firmware version 34.0.0 op_mode iwlmvm [    6.248314] iwlwifi 0000:00:14.3: Detected Intel(R) Dual Band Wireless AC 9560, REV=0x318 [    7.264081] iwlwifi 0000:00:14.3: SecBoot CPU1 Status: 0x3, CPU2 Status: 0x2477 [    7.264084] iwlwifi 0000:00:14.3: Failed to start INIT ucode: -110 [    7.276165] iwlwifi 0000:00:14.3: Failed to run INIT ucode: -110   sudo modprobe iwlwifi returns no output. Solve for $x$: $2^x=4x$ Given that $x$ is a positive integer. By using methods of trial and error as well as plotting two lines: $y=2^x$, $y=4x$ on a graph and find their intersection point, we can easily solve for $x$ which is equal to 4. However, I do not know how to solve this using only equation. Can anyone help me? Prevent malicious bots from posting spam I remember  due to misuse and I wonder if bots have a part of it. If the bot is POSTing something to my site what are ways I can combat it? I was thinking of setting some cookies and having the cookies changed via JavaScript + timestamp and sign (so yesterday's cookies can't be used today and next week).  I'm sure most people/bots would just use another site instead of enabling JavaScript in their bot.  What else can I do? I'm thinking daily POST limit and a honeypot for generic bots who just randomly post spam. Filter a Python list by predicate I would want to do something like:  &gt;&gt;&gt; lst = [1, 2, 3, 4, 5] &gt;&gt;&gt; lst.find(lambda x: x % 2 == 0) 2 &gt;&gt;&gt; lst.findall(lambda x: x % 2 == 0) [2, 4]   Is there anything nearing such behavior in Python's standard libraries?  I know it's very easy to roll-your-own here, but I'm looking for a more standard way. What are some alternatives to "hover" on touch-based devices? Came up recently in a 37signals podcast:    The straightforward, "brute-force" solution is to just use the first touch on a UI object as the hover.    It works. But are there other, more elegant solutions? For instance, could the hardware ever be made to support actual finger hovering? Incorrect bookmarks and page number in table of contents I have problem with table of contents and with bookmarks. In pdf file   table of contents shows wrong page number of Introduction and Bibliography, Bookmarks: introduction and bibliography don't bring me to the correct page.   Part of my code  \documentclass[12pt,a4paper]{book}  \usepackage[polish]{babel} \usepackage{polski} \usepackage[cp1250]{inputenc} \usepackage[pdftex,pagebackref=false,draft=false,pdfpagelabels=false,pdfstartview=FitH,pdfstartpage=1,bookmarks=true,pdfauthor={LiN},pdftitle={PD},pdfsubject={Titlei},pdfkeywords={words},unicode=true]{hyperref}  \usepackage{tocloft}  \begin{document} \tableofcontents \addcontentsline{toc}{chapter}{Introduction} \chapter*{Introduction} \chapter{Chapter1} \section{Section} \addcontentsline{toc}{chapter}{Bibliography} \begin{thebibliography}{9999999}% \bibitem{1}Author, \emph{Title of book}, Publisher. \end{thebibliography} \end{document}   How can I change that? How to make a pattern follow a stroke, path or line? Here is my MS Paint job on a real bad attempt at what I'm trying to achieve:    I have access to Photoshop and Illustrator CS6, and I want to be able to draw a thick line (that is not straight) and have a pattern within the line show arrowheads within the line to indicate the direction of the line. What are the basics of commands in Minecraft Java Edition? What are the basics of Minecraft commands? If I were to start from scratch, with no knowledge on the topic, what are some things that I need to know? About multi-root search in Mathematica for transcendental equations How does QGIS Zonal Statistics handle partially overlapping pixels? Proof of a basic $AC_\omega$ equivalence On  it is mentioned that "...  in order to prove that every accumulation point $x$ of a set $S\subseteq \mathbf R$ is the limit of some sequence of elements of $S\setminus \{x\}$, one uses (a weak form of) the axiom of countable choice. When formulated for accumulation points of arbitrary metric spaces, the statement becomes equivalent to $AC_\omega$. ..."  I have Herrlich's paper "Choice principles in elementary topology and analysis" where in theorem 2.4. it is stated that these are indeed equivalent. Then I looked up the reference he quotes, [4], which are Bentley H.L., Herrlich H., Countable choice and pseudometric spaces which does not contain the proof and  does also not contain the proof, hence my question:   Where can I see a proof of      "if $S$ is a set in a metric space $X$ with accumulation point $s$   then there exists a sequence $s_n$ in $S$ converging to $s$"   $\implies$ $AC_\omega$   ? (the other implication is clear to me). Thanks. Trouble Viewing Whole HDR Image as cycles world When I load an HDR image into an environment texture using Cycles Render, only a small fraction of the image appears. I have a feeling it's an easy fix, but I can not find what needs to be changed. My current idea is to use the dual graph, and prove that that is a bipartite graph, and so proving the statement. But I can't seem to figure out how even degree for all verticies means that it is bipartite.  Any help is appreciated. Thanks! How do I add newlines between lines printed on the command line? Mail logs are incredibly difficult to read. How could I output a blank line between each line printed on the command line? For example, say I'm grep-ing the log. That way, multiple wrapped lines aren't being confused.