Sometimes there is a need to be sure that no identifier is processed twice – for example, when parsing a file into a database, with file potentially containing duplicate records. An obvious solution is to properly wrap the DB insertion code into try…except block, and process duplicate primary ID exceptions. Another, sometimes more desired solution is to maintain a set/list of processed IDs internally, and check against that list prior to attempting the insertion of anything. So is it a set or a list?

There are already quite a few internet resources discussing “python set vs list”, but probably the simplest while elegant way to test that is below.
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Phusion Passenger Apache users guide

Also as a PDF.

Inspired by video encoding with handbrake.

HandBrake is a very high-quality piece of software – next time you need recoding something into H.264/MPEG-4 (using MKV or MP4 containers) – try HandBrake. It easily saturated all my CPU cores – which I failed to achieve with ffmpeg, which even with threads=8 was only saturating 2 cores.

Attached to this post are 2 profiles for recoding movies for Nokia E71. The “_best” profile has exhaustive motion detection, otherwise is identical to the base profile.
E71.plist
E71_best.plist

Related:

• x264 ffmpeg mapping and options guide
• ffmpeg audio/video encoding cheat sheet

Amarok moodbar wiki page has 2 nice scripts to generate .mood files for your whole music collection (to be displayed by amarok when playing).

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Under a few assumptions (most importantly – you do not have any non-merged branches,), it is very easy to throw away git repository commits older than an arbitrarily-chosen commit.

Here’s a sample script (call it e.g. git-truncate and put into your ~/bin or whichever location you have in PATH).


#!/bin/bash
git checkout --orphan temp $1
git commit -m "Truncated history"
git rebase --onto temp $1 master
git branch -D temp
# The following 2 commands are optional - they keep your git repo in good shape.
git prune --progress # delete all the objects w/o references
git gc --aggressive # aggressively collect garbage; may take a lot of time on large repos


Invocation: cd to your repository, then git-truncate refspec, where refspec is either a commit’s SHA1 hash-id, or a tag.

Expected result: a git repository starting with “Truncated history” initial commit, and continuing to the tip of the branch you were on when calling the script.

If you truncate repositories often, then consider adding an optional 2nd argument (truncate-commit message) and also some safeguards against improper use – currently, even if refspec is wrong, the script will not abort after a failed checkout.

Thanks for posting any improvements you may have.

Source: Tekkub’s post on github discussions.
See also: how to remove a single file from all of git’s commits.

Imagine you need to install pycassa (which uses easy_install). Here are the 2 (at maximum) very simple steps to have it properly debianized and installed on your Debian/Ubuntu:

• if you don’t have the python-stdeb package: sudo aptitude install python-stdeb
• pypi-install pycassa

That’s it.

Refer to stdeb readme for more information. You will need that if there are dependencies – which might not be resolved automatically by stdeb.

Before stdeb, it wasn’t exactly trivial to make a .deb from python module.

wget ––continue ––mirror ––page-requisites ––adjust-extension ––convert-links ––backup-converted ––limit-rate=500k ––wait=2 URL

(short form: wget -cmpEkK ––limit-rate=500k -w 2 URL)
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