Various code snipplets below are all under BSD-license, so you can integrate them in any commercial project. We would appreciate if you send us back any bug fixes or extensions. We will mention your contribution on this page.

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Ruby hack to get a linux standard printer to print windows stuff

Stefan's daughter Helena complained that she can't print out any pictures on the windows notebook, as only his linux box has a printer attached (no network printing configured). Therefore the following script allows to forward the stuff to a standard printer. Only set up a ps-printer with raw-connection on the windows box and set the correct IP and port in the script. Version 0.02 can listen on a vmware ip-address -- which first needs to configured manually (depending on what ifconfig says about vmnet).

printerproxy.rb (Version: 0.02) last changes: 15/01/2003

Ruby code for Cholesky Decomposition

If certain conditions are met, one can write a matrix A as A=L * transpose(L). The code below works out L. If the code fails, check first whether your matrix can be Cholesky decomposed using real numbers only.

Download code and tests: Cholesky (Version: 0.01) last changes: 12/24/02