I could not find a solution for the following problem. That's why I address my problem now here.  I want to design a table without fancy libraries, just with some basic features like \hline and spacing commands. But this strategy does not lead me on the right way.  I attached a picture of the compiled latex code. You can see small white gaps in the vertical lines. How do I get rid of those? It is supposed to be a continuous line.  \begin{table}[ht] \centering \caption[bla]{bla } \begin{tabular}{| p{1.8cm} | p{3cm} | p{4.7cm} | p{3.5cm} |}     \hline \\[-1.0em]     bla     &amp; bla &amp; bla &amp; bla \\     \hline \hline \\[-1.0em]     bla &amp; bla  &amp; bla &amp; bla \\     \hline \\[-1.0em]     bla &amp; bla &amp; bla  &amp; bla \\     \hline \\[-1.0em]     bla &amp; bla &amp; bla &amp;bla\\     \hline \\[-1.0em]     bla &amp; bla &amp;bla Jahre &amp;  bla \\     \hline \\[-1.0em]     bla &amp;bla   &amp; bla &amp;bla \\     \hline \end{tabular}% \label{tab:bF}% \end{table}%     Thanks a lot for your support!
I have seen similar questions on the matter (, ) of adding vertical space and not breaking vertical lines, the solutions suggested are to add space after the \\ using \\[0.1cm] for example or changing the \arraystretch which I do not want to do. Using \\[0.1cm] allows me to add space just before a \hline but not after as well.  How can I add vertical space after a \hline without breaking vertical lines in a table?  Please find my MWE below:  \documentclass{scrreprt} \usepackage{setspace} \usepackage[left=2.5cm,right=2.5cm,top=3cm,bottom=3cm]{geometry} \usepackage{array,tabularx} \doublespacing  \begin{document} \begin{table}[htb]   \centering   \onehalfspacing   \caption{Table of info.}      \begin{tabular}{c | c c}  &amp; C/S Analyser &amp; O/N/H Analyser \\  &amp; EMIA 320 V2 &amp; EMGA 830 \\[0.1cm]    \hline    \noalign{\vskip 0.1cm} Sensitivity (ppm) &amp; 0.1 &amp; 0.001 \\ Furnace type &amp; Induction &amp; Impulse \\ Carrier gas &amp; Pure O2 &amp; Pure He \\[0.1cm]    \hline     \end{tabular}    \doublespacing   \label{tab:chem} \end{table} \end{document}
Can the Universe be deterministic and still allow free will? How do I search for available packages from the command-line? I have successfully installed some packages using the command line 'sudo apt-get install packagename' when I have known in advance that those packages are available.  But how can I search for or get a list of what is available in the repositories? What are the visa (or any other crucial) requirements of Bhutan for tourists? I heard that access to Bhutan is quite restricted for all people of outside South-Asian countries?  Can I have the details on that? The company I work for makes hardware that communicates to the computer though a serial port. Third party companies write software that communicates with our hardware.   There are times when I need to diagnose our hardware. However, a third party software app connects to the serial port when Windows starts up, blocking any other connection. 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I've looked for forums dedicated to these kinds of OCW courses but have not been able to find any.  This surprises me.  It seems like, with the advent of these free online educational resources, an online meeting place for those who take advantage of them would be a natural offshoot.  So this might be a bit of an experiment.  Unless I'm the 873rd person to post something like this here.  If that's the case, sorry for being so long winded.  Anyway, on with the question.  This one is assigned in the 4th lecture.     Let $V$ denote the Klein 4-group.  Show that $\operatorname{Aut}(V)$ is isomorphic to $S_3$.   (I've moved my solution below to keep this question from showing up in the unanswered list.)  Thanks... "Stay home" or "stay at home" – which is correct and why? What is the right ffmpeg output format for a v4l2-loopback device? 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If so, what should I use instead? I tried h264 but that crashes after ~1000 frames with following error message:  $ ffmpeg -f x11grab -r 15 -s 1280x720 -i :0.0+0,0 -vcodec rawvideo -pix_fmt yuv420p -threads 0 -f h264 /dev/video0 ffmpeg version 4.0 Copyright (c) 2000-2018 the FFmpeg developers ... [x11grab @ 0x55da61e29cc0] Stream #0: not enough frames to estimate rate; consider increasing probesize ... File '/dev/video0' already exists. Overwrite ? [y/N] y .... Error writing trailer of /dev/video0: Invalid argument .... Conversion failed! Why does ( exit 1 ) not exit the script? How do I make Subversion (SVN) send email on checkins? I've always found checkin (commit) mails to be very useful for keeping track of what work other people are doing in the codebase / repository. How do I set up SVN to email a distribution list on each commit?  I'm running clients on Windows and the Apache Subversion server on Linux. The answers below for various platforms will likely be useful to other people though. Why does find -mtime +1 only return files older than 2 days? I'm struggling to wrap my mind around why the find interprets file modification times the way it does.  Specifically, I don't understand why the -mtime +1 doesn't show files less than 48 hours old.   As an example test I created three test files with different modified dates:   [root@foobox findtest]# ls -l total 0 -rw-r--r-- 1 root root 0 Sep 25 08:44 foo1 -rw-r--r-- 1 root root 0 Sep 24 08:14 foo2 -rw-r--r-- 1 root root 0 Sep 23 08:14 foo3   I then ran find with the -mtime +1 switch and got the following output:  [root@foobox findtest]# find -mtime +1 ./foo3   I then ran find with the -mmin +1440 and got the following output:   [root@foobox findtest]# find -mmin +1440 ./foo3 ./foo2   As per the man page for find, I understand that this is expected behavior:   -mtime n         File’s  data was last modified n*24 hours ago.  See the comments         for -atime to understand how rounding affects the interpretation         of file modification times.   -atime n        File  was  last  accessed n*24 hours ago.  When find figures out        how many 24-hour periods ago the file  was  last  accessed,  any        fractional part is ignored, so to match -atime +1, a file has to        have been accessed at least two days ago.   This still doesn't make sense to me though.  So if a file is 1 day, 23 hours, 59 minutes, and 59 seconds old, find -mtime +1 ignores all that and just treats it like it's 1 day, 0 hours, 0 minutes, and 0 seconds old?  In which case, it's not technically older that 1 day and ignored?   Does... not... compute. Integral inequality with a strange condition Let $f$ be a continuously differentiable real valued function on $[0,1]$.  It is given that $\displaystyle \int_{\frac{1}{3}}^{\frac{2}{3}}f(x) dx=0$     Find the minimum value of $\dfrac{\int_{0}^{1} (f'(x))^2 dx}{\left( \int_{0}^{1} f(x) dx \right)^2}$   I tried to use Cauchy-Schwarz to show that  $$\frac{\int_{0}^{1} (f'(x))^2 dx}{\left( \int_0^1 f(x) dx \right)^2} \ge \frac{\left( \int_0^1 \bigl| f(x)f'(x) \bigr| dx \right)^2}{ \left( \int_0^1 f(x) dx \right)^2} \ge \frac{ f(1)^2 - f(0)^2}{2 \left( \int_0^1 f^2 (x) dx \right)^2}$$ But I can't proceed from here.  Also, I don't know how to use the condition  $\int_{1/3}^{2/3}f(x) dx=0$ I need to echo a string containing angle brackets (&lt; and >) to a file on a Windows machine.  Basically what I want to do is the following: echo some string &lt; with angle &gt; brackets &gt;&gt;myfile.txt  This doesn't work since the command interpreter gets confused with the angle brackets.  I could quote the whole string like this: echo "some string &lt; with angle &gt; brackets" &gt;&gt;myfile.txt  But then I have double quotes in my file that I don't want.    Escaping the brackets ala unix doesn't work either: echo some string \&lt; with angle \&gt; brackets &gt;&gt;myfile.txt  Ideas? Can you nest html forms? Disk Utility cannot erase USB drive (error -69877: couldn't open device) Disk Utility (macOS Catalina 10.15.2) fails to erase my USB drive (64GB key, currently formatted in exFAT).  /dev/disk2 (external, physical):    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:      GUID_partition_scheme                        *64.1 GB    disk2    1:                        EFI EFI                     209.7 MB   disk2s1    2:       Microsoft Basic Data Lexar                   63.9 GB    disk2s2   I've tried a bunch of commands that I've found here and there in the terminal, but none of them worked, like:  ➜  ~ diskutil eraseVolume exFAT MyName /dev/disk2 Started erase on disk2 Unmounting disk Error: -69888: Couldn't unmount disk   ➜  ~ diskutil eraseVolume exFAT MyName /dev/disk2s2     Started erase on disk2s2 Lexar Unmounting disk Erasing Error: -69760: Unable to write to the last block of the device   ➜  ~ diskutil eraseDisk FAT32 MYSD MBRFormat /dev/disk2 Started erase on disk2 Unmounting disk Creating the partition map Error: -69877: Couldn't open device   ➜  ~ diskutil eraseDisk free EMPTY /dev/disk2 Started erase on disk2 Unmounting disk Creating the partition map Error: -69877: Couldn't open device   My USB drive appears as read only when i do CMD+I, I tried repairing the permissions but that failed too.  ➜  ~ diskutil resetUserPermissions /dev/disk2 `id -u` Ready to reset user permissions on disk2 Error encountered attempting to reset permissions for user 501 home directory on disk2: Permissions are not enabled on the disk (-69861)   Thx in advance for the help :) Is there any quality difference between PNG vs BMP image formats? 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