[PYTHON MATRIX-SIG] Bug in LinearAlgebra

Doug Heisterkamp drh@cse.unl.edu
Wed, 16 Oct 1996 09:04:22 -0500 (CDT)


> 

I added the determinant function to LinAlg.py as an afterthought just before 
sending it to Jim.  It was a very poor thought, considering it was wrong and
the name was not even spelled right!

Just want people to know that Jim did not mess up the determinate.

Doug Heisterkamp
drh@cse.unl.edu


> > > Here's the fixed (but not really tested) version of determinant:
> > > 
> > > def determinate(a):
> > >     _assertRank2(a)
> > >     _assertSquareness(a)
> > >     ev = eigenvalues(a)
> > >     return Numeric.product(ev)
> > 
> > If somebody more LA familiar than myself can confirm and test this I'll
> > make the change in the standard distribution.
> 
> That is indeed a correct way to calculate the determinant, although
> not the most efficient one (LU decomposition is faster). If I find the
> time I'll do something better, but this one is of course much
> preferable to the current (wrong) function. But please also correct
> the name to "determinant"!
> 
> Konrad.
> -- 
> -------------------------------------------------------------------------------
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