[comp.theory] matrices

clc8347@tamunix (Cheryl Cato) (02/27/90)

I realize this is a very elementary problem, which probably
has been answered many times here -- but I'm new to the news
groups and am in desparate need of some help....

I need to find the determinants of a 4 x 4 (or less)
matrix - program to be written in C.  The Gaussian
Elimination, I've been told, is very unreliable and
very hard to code.  My ultimate goal is to solve for
loop currents in an RLC circuit.

Any help available?

Thanks!

Cheryl Cato
clc8347@tamunix.tamu.edu

bs@linus.UUCP (Robert D. Silverman) (02/27/90)

In article <4411@helios.TAMU.EDU> clc8347@tamunix.tamu.edu (Cheryl Cato) writes:
:I realize this is a very elementary problem, which probably
:has been answered many times here -- but I'm new to the news
:groups and am in desparate need of some help....
:
:I need to find the determinants of a 4 x 4 (or less)
:matrix - program to be written in C.  The Gaussian
:Elimination, I've been told, is very unreliable and
:very hard to code.  My ultimate goal is to solve for
:loop currents in an RLC circuit.

You have been grossly misinformed. Gaussian elimination is both simple
and easy to code - it takes less than a page of C code. It is numerically
reliable when done with partial pivoting.

See the following:

"Numerical Recipes", by Press, Flannery, Teukolsky, & Vettering

or 

"Matrix Computations" by Golub and Van Loan.

-- 
Bob Silverman
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