On 12/17/2012 12:45 PM, Toon Van Assche wrote:
Dear all,

Running Stage 4.1.1 & Player v.3.1.0-svn @ Ubuntu 12.04 LTS.
I would like to take the inverse of a nxn matrix to use in my GraphSlam.

The issues that I encountered:
- .inverse() Eigen-library (3.1.2) doesn't allow zero values, returns NaN
- The LAPACK (3.4.2) library doesn't allow to use negative values, allows zero values 
(used this example code http://stackoverflow.com/questions/3519959/computing-the-inverse-of-a-matrix-using-lapack-in-c
- Pseudo inversion doesn't seem to allow negative values either
- Seldon (5.1.2) wouldn't compile for some reason 

Did anyone successfully implemented an nxn matrix inversion code that allows negative and zero-values.
Any good library recommendations?

All help would be appreciated,

Regards,

Toon


Can you provide an example of a matrix you're trying to invert that isn't working?  The presence of zeros or negative numbers doesn't necessarily have any bearing on a matrix's invertiblity, but if you're trying to invert a singular matrix or a matrix that isn't full rank then you're going to have issues no matter what library you use.

Rich