Scilab

kronecker.sci

A scilab script that transformes a real matrix pencil B*s-A into a lower triangular block matrix pensil Bt*s-At. The four diagonal blocks of this pencil have the following structure:

the first one has the same Kronecker column indices as B*s-A
the second one has the same finite eigenvalues as B*s-A
the third one has the same infinite eigenvalues as B*s-A
the fourth one has the same Kronecker row indices as B*s-A

A first test is provided in kronecker-test.sci.

Note, that there is also a Kronecker-pencil algorithm called kroneck built into Scilab (see the Scilab-documentation for more details).

Thanks to Ricardo Zavala Yoe for testing the package and reporting a bug (which is already fixed).

nonlin_string.sci

A scilab script that computes the motion of a sustained string.

The string is assumed to have linear elastic properties but the geometrical nonlinearities are regarded.

To run the script download it to a local directory, change to that directory, launch scilab and run the command

exec("nonlin_string.sci");

After some computing time a graphics window with the moving string should pop up.

A snapshoot is shown in the following picture:

Enjoy the show!