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Information Visualization

Since I had done the visualization class at grad school, the world wans't the same anymore. To look at informational illustrations and graphic plots is being a real cool exercise. And when I have to use some software to plot some chart, quickly come back to my mind when our professor were telling us if we went to his office, he will receive us with a box of paper tissue to wipe our tears away...

So, when I read the slashdot article about a Ronald Knief collecting charts of nuclear reactors, originally published in issues of Nuclear Engineering International, I became very curious.

But after reading those articles I had reached the BibliOdissey blog, which has much more digitized illustrations, from artistic illustrations, through info charts, to puzzles. It is really awesome... It has lots of illustrations. They are all hires illustrations, the BibliOdissey has a Flickr gallery with them in 5156 x 3244.

Here are some of my favorites:



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uSleep on windows (win32)

I am facing a terrible issue regarding timing on windows.

Googling arround, I've found those infos:
Using QueryPerformanceCounter and QueryPerformanceFrequency APIs in Dev-C++
(http://yeohhs.blogspot.com/2005/08/using-queryperformancecounter-and_13.html)
QueryPerformanceCounter() vs. GetTickCount()
http://www.delphifaq.com/faq/delphi_windows_API/f345.shtml
How to time a block of code
http://www.cryer.co.uk/brian/delphi/howto_time_code.htm
And Results of some quick research on timing in Win32 http://www.geisswerks.com/ryan/FAQS/timing.html
With that I'm trying to write something like a uSleep function for windows:


#include<windows.h>

voiduSleep(int waitTime){
__int64 time1 = 0, time2 = 0, sysFreq = 0;

QueryPerformanceCounter((LARGE_INTEGER *)&time1);
QueryPerformanceFrequency((LARGE_INTEGER *)&freq);
do{
QueryPerformanceCounter((LARGE_INTEGER *)&time2);

// }while((((time2-time1)*1.0)/sysFreq)<waitTime);
}while( (time2-time1) <waitTime);
}

There is also already a nanosleep…

More trickery with gnuplot dumb terminal

In my post "Plotting memory usage on console" the chart doesn't pan the data.
Now, using a named pipe, the effect got a little bit nicer.
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./memUsage.sh > memUsage.dat &
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mkfifo pipe
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while [ 1 ]; do tail -64 memUsage.dat> pipe; done &
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watch -n 1 'gnuplot -e "set terminal dumb;p \"pipe\" with lines"'
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First I did a grep for fail at the /var/log/auth.log. (grep -i /var/log/auth.log)

And I got lots of lines with the string "fail". With [grep -i /var/log/auth.log | wc -l] I figured out that were 1164 fail entries at auth.log

With an [grep -i fail auth.log | cut -d " " -f 6 | sort | uniq] I checked that were two kind of failed attempts:
Failed
pam_unix(sshd:auth):

So I wrote the following line to check with which users they were attempting to log:
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Here, the field position (the number 11 at the above command lines [-f 11]) may change in some systems. At my desktop at work, the username came at the position 9.

Here are the "top ten":
root 2922
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