Warning singular matrix.

I am using \ to solve a system of linear equations. I get a warning telling me the matrix is singular or ill conditioned. This only happens sometimes as my program is recursive. In the event that this happens, there is a 'fall back value I would like to assign as the solution. How could I implement something like an if statement like:

if(warning) x=this instead end

I was reading about dbstop, but that doesn't seem to do what I want.

Thanks,

Chris

Answer 1

[the cyclist]

There is the try() command, as part of the try-catch structure, but I think that only works for error-trapping, not warning-trapping. That would be a nice feature.

You should be able to use the lastwarn() command to create something like the same thing. Specifically, I am thinking you could execute the lastwarn() command just after your code, and use the output to determine whether to assign your "fall back" value.

Answer 2

[Sean de Wolski]

You could check if any of the result isinf

if any(isinf(result(:))) %is it singular?
  x = this_instead; %yeah, doh!
end