Smooth

I wanted to be able to generate Gnuplot images of my SPH results for an arbitrary number of state files. Thanks to the magic of shell scripting, I can!

Here is a bash script:


#! /bin/bash
ls sphstate.* > list
for i in `cat list` ; do
echo item: $i
sed -e "s/INPUTFILE/$i/" -e "s/OUTPUTFILE/$i/" sphplot.plt | gnuplot
done


Here is a gnuplot script:

set term png small
set output "OUTPUTFILEtemp.png"
plot "INPUTFILE" using 1:7 title "temperature"


Here are a few URLS:
Sed tutorial
Gnuplot IFAQs (recommended)
Bash scripting guide

rsync -av username@host:sourcedir/ destdir/

e.g.

rsync -av andy@apac.com:~/ ~/mybackupfolder/monday1/

The slashes on the ends specify to copy the contents of the folders and not the folders themselves.

To use wildcards, use –include and –exclude flags e.g. rsync -avtubz –include=’/sa_*’ –exclude=’/*’ ac@source.com:~/ ~/backup/

Include arguments override subsequent exclude arguments.

http://blogs.warwick.ac.uk/chrismay/entry/idiots_guide_to/

I just wasted hours as a result of a “feature” of Edgy, the distro of Ubuntu I’ve installed on my new deck. The developers have replaced bash with dash as the shell that is invoked by scripts using #! /bin/sh

This has the effect of breaking scripts that rely on bash extensions. Apparently it is the script writers who are to blame – thing is I don’t care! What bugs me is that the process of installing my fortran compiler, so that I can get to work, was made more difficult. The developers who’ve stuck by this change have decided that trying to enforce a standard is more important than the usability of their software. One more truly annoying Ubuntu experience like this and I will start shopping for another distro.

https://launchpad.net/ubuntu/+source/dash/+bug/61463

There are several solutions to this – you can modify the scripts that fail such that they use bash (change #! /bin/sh to #! /bin/bash), or more simply you can change the symbolic link sh, found in the /bin directory, to point to /bin/bash. I went as far as uninstalling the dash shell on principle.

*Edit* Now that I’ve cooled down, I’ve reinstalled dash. The argument in favour of the change is a speedup of shell script execution, which it’s claimed leads to significantly faster startup times. Might as well make the most of it.

My shell skills are a little rusty. Now that I’m relying on Ubuntu to be my main OS for development and writing, I better sharpen, cut and buff them.