Thread Subject: Matrix inversion

Am trying to learn MATLAB,i formed a matrix which has large values,zeros and ones,when i try to get the inverse it says matrix is singular.Question is how can i combine very small values with very large values to form one matrix?

"Katula " <ssengendo_ronald@yahoo.co.uk> wrote in message <geft5a$bbp$1@fred.mathworks.com>...
> Am trying to learn MATLAB,i formed a matrix which has large values,zeros and ones,when i try to get the inverse it says matrix is singular.Question is how can i combine very small values with very large values to form one matrix?

  There is no reason why a non-singular matrix cannot have both very small and very large values at the same time. It all depends on what those values are.

  When Matlab declares that it deems a matrix to be "singular" it means that within computable accuracy the matrix has a zero value for its determinant, which in turn means that it can possess no inverse. If it does in fact have an inverse in a mathematical sense, Matlab is unable to determine that inverse with any reasonable accuracy because of inherent round-off errors.

Roger Stafford