Backing up CDs in Linux

1) Sound Juicer to copy as OGGs.
2) Sound converter to convert OGGs to mp3.

Here's a link to the latter, as it's an install option.

Line-by-line Sorting of a list in bash

Take "collab.lis" as the file with the list to sort, and route it to a file called "junk.lis"

less collab.lis | tr "" "\n" | sort > junk.lis

Simple as that.

CCfits

CCfits is a wrapper for the cfitsio C routines that are useful for manipulating fits images. I would like to see how useful C++ might be for astro applications, and maybe eventually adopt Python for prototyping code and C++ for writing fast, efficient code.

To install cfitsio and CCfits, I just followed the documentation with the normal configure/make/install steps. The only minor hitch was getting the CCfits ./configure script to point at the right cfitsio library locations.

I had to dust off my C++ books and remember a few things to actually get the gcc/g++ compiler up and running. For gcc/g++, I spent most of my time remembering the header/library system of doing things. Not sure my terminology is kosher here, but you need to point the compiler to the right "include" path (containing function declarations) correctly link to the library (containing the actual definitions). I ended up using something like:

g++ -I/usr/local/include/CCfits -lCCfits cookbook.cpp

to successfully compile and run the CCfits test routine. Without the include path, all kinds of errors involving the std:: namespace were returned, and with the "-lCCfits", the CCfits:: were compiled with numerous errors.

Finally, if you try to run the executable without setting the "LD_LIBRARY_PATH" environmental variable to the location of the shared library, it complains about not finding "lCCfits.so.0" during runtime.

Use Wget through a proxy

This worked really well:
http://blog.taragana.com/index.php/archive/how-to-use-wget-through-proxy/

Since I'm in tcsh, I just used
setenv http_proxy ......

I'll make sure when I get home that it doesn't screw things up when not using the proxy, in which case we have to remember to comment things out.

apply pixel mask

This is going to be an on-going post about making this piece of code run, . I'm just going to add to it bit-by-bit until I have something complete. Usually the first thing to check is:

setenv LD_LIBRARY_PATH /usr/local/lib/

in your .cshrc. There are other steps required, but on my current libraries, installed on a new machine, this is the thing I forget to add most often. /usr/local/lib is where I usually keep all the needed C/C++ libraries, but it certainly change if you move to other machines.

IDL color tables

It often happens that when I go to a new computer and run IDL, the color tables don't work. The simplest fix to try is usually the following:

IDL> device,decomposed=0

Then loading the color table is as simple as:

IDL> loadct,1 ;; or no number will list the available color tables

Running after Logout

I've had different levels of success with this. If you just place a command in the background with bg, it will still die after logout. Sometimes 'nohup' works, but I'm not sure when or why. It probably has something to do with display type or somthing.

The reason I'm so interested in this is that I often issue 'wget' commands from my laptop that transfer large amounts of data between two remote computers. This was where I got most of my help.

I used "screen", but I didn't do everything smoothly, which probably isn't smart. Screen opened up a different looking terminal in the shell, from which I issued the command. I couldn't get out of the window, so I just clicked "close" on my laptop. After logging back in, I saw that the command continued to run. I'm sure there's a more graceful way to do this, using some screen commands, etc.