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There is a lesser known command, jpilot-dump, to print portions of J-Pilot files. Here is an example to print category, first name, last name: jpilot-dump -A +A"%C %f %l" | less And here is another command: jpilot-merge.
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Recently I installed an additional SATA drive on my Lenovo laptop. Without much ado I formatted the drive to ext4. Unfortunately, I quickly realized that the hard drive is spinning almost twice a second. My first drive on the laptop is also formatted with ext4, so using ext4 was a natural choice. A…
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I wanted to see what files and when J-Pilot accesses its pdb and pc3 files. In my case strace produces much more output than actually needed. But inotifywait shows what and when files are accessed. inotifywait -m .jpilot/ inotifywait is in Debian/Ubuntu package inotify-tools. Here is an example…
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My other son had a practical training at Fraunhofer IGD. He wrote an OpenGL/C++ program in Windows where one views the earth rotating around the sun, thereby with its rotating moon, see picture below. openglSunEM-X I ported this program to Gtk/Linux. You'll find the code in openglSunEM.c. The link…
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A couple of years ago I went through Otto Forster's Analysis 3 book for self study of differential forms. I thought the presentation could be leaned more towards matrices and determinants, which since Bourbaki's time got a difficult stand in mathematics. Here is the document: On Differential…
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Very inspirational and motivating speech held by Dean Kamen:
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Since using Alpenfoehn Gotthard CPU cooling has improved and the whole PC is more silent. On an otherwise idle PC, just xterm and Chrome running: $ modprobe it87 $ iostat avg-cpu: %user %nice %system %iowait %steal %idle 1.25 0.00 0.25 0.17 0.00 …
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I was asked by a colleague of mine how many combinations are possible for the German tax id. The German tax id is built entirely from eleven digits. Its specification is given in Pruefziffernberechnung, see Steueridentifikationsnummer in the German Wikipedia. Every person reported to live in…
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According the Bloomberg interview as of March 28, 2011, with Matt Mullenweg, https://wordpress.tv/2011/03/28/bloomberg-mullenweg/, it costs 300-400.000$ per month to maintain 1.300 servers operating WordPress.
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I wanted to write a short benchmark for my son to demonstrate that the AMD Bulldozer 8 core CPU is better than a 6 core CPU from AMD when computing with integers. So I wrote a short C program to compute a recurrence relation using integers only, see C code below. When I ran this program on one…
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Mein erster Eindruck von WordPress ist sehr gut. Die Schrift ist angenehm groß, die Bedienung einfach.
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