Re: What does "Singular matrix in routine LUDCMP" mean?
Gary Hall - (hall++at++vsl.ist.ucf.edu)
Thu, 27 Apr 95 14:51:10 EDT
>
> On Apr 27, 1:39pm, Robert Webb wrote:
> > Subject: What does "Singular matrix in routine LUDCMP" mean?
> :
> :When I run my Performer application, I sometimes get the message:
> :
> :"Singular matrix in routine LUDCMP"
> :
> :There is no mention of LUDCMP in any gl documentation I can find. It
> :probably just means I've got a matrix of all zeros on the stack or
> :something, but could someone clear this up for sure. Any pointers on why
> :this might be happening (sometimes) would also be ace.
>
> Good point. The warning was not sufficiently specific. This warning
> is from the "Lower-Upper-Decomposition" routine that's part of
> IRIS Performer's pfInvertMat() function. Not all matrices can be
> inverted, just as the scalar zero has no multiplicative inverse. In the
> case of matrices, it's those with one or more zeroes on the main
> diagonal. When we try to invert such a matrix, the function
> pfLUDecompMat() prints the warning and returns a failure notice
> to pfInvertMat(), which returns a failure notice in turn.
>
> :Has anyone else had this problem?
>
Sometimes I get the error:
gl_invert3d: ERR_SINGMATRIX
Which is a gl error, but happens in my Performer app.
Sounds similar to above error.
--
Gary Hall 407-658-0041
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on Mon Aug 10 1998 - 17:51:26 PDT