[LON-CAPA-dev] Installing Modules for LON-CAPA

GARRETT, DONNELL MAZON lon-capa-dev@mail.lon-capa.org
Mon, 26 Sep 2005 12:29:34 -0400


Hi

I've emailed Gerd Kortemeyer a few times about maybe trying to extend
LON-CAPA's math capabilities.  He emailed me back and said that LON-CAPA
does in fact have the concept of a library so that new
functions/subroutines can be added.  This is music to my ears, as I told
him.

Last week after a little prodding the Electrical Engineering department
got their own CAPA server off the ground and working.  Since then, I've
been playing around with making different types of problems and I think
it's awesome.

Now, this is what I'm trying to do.  We want to solve simultaneous
equations.  For example, if:

x + y = 10
x - y = 2

We would want to be able to put them into a matrix and solve for x and
y.  This example is very simple, but later on when we get into trying to
solve simultaneous equations with circuits with a lot of different
elements, we are going to need some way to solve matrices.  Also, since
the script for problems is basically just Perl, we could write out how
to solve for these equations every time, but that would be a pain for
someone who is not familiar with Perl at all (which will be anyone
except me here in the EE department).

What I'm really looking for is for how to add things to this library.  I
did some poking around on the internet, and I found that there is a
module called Math::Cephes:Matrix on CPAN
(http://search.cpan.org/~rkobes/Math-Cephes-0.42/lib/Math/Cephes/Matrix.
pm).  It solves for simultaneous equations automatically and also gives
a lot of other useful matrix type features.  Likewise, there is a
Math::Cephes:Complex on CPAN
(http://search.cpan.org/~rkobes/Math-Cephes-0.42/lib/Math/Cephes/Complex
.pm) that deals with complex numbers, something we'd also like to
calculate later on.  It'd be great if we could get these two modules so
that when we write the script we can access functions/subroutines from
these modules and make better problems.  Also, I noticed that in one of
your documents
(http://s10.lite.msu.edu/adm/help/Script_Functions.hlp#Script_Functions)
that you "support" a few statistical functions from Math::Cephes.  That
is great.  If you are already using it, then it must be possible to
obtain usage of the other parts of Math::Cephes.  

That's what I'm trying to do..  Just figure out how we can use the perl
script in problems to take the randomly generated inputs and use
matrix/complex number functions and produce the outputs/answers based on
the inputs.  

Thanks for helping me out,
Donnell