Estimating Condition Number
The convergence of iterative methods like conjugate gradient depends highly on the condition number of the matrix. I use a preconditioned conjugate gradient (with a gauss-seidel preconditionner or ILU(0)) and I would like to know if there is a way to estimate the condition number of the matrix easily. The matrix system arises from the basic structural equations of mechanic in large deformation. Is there any estimate that can be easily computed (I have in mind a method which uses element aspect ratio for example...). My goal is to have more control on the solving process and to have the ability to predict when the solver will fail.
Thank you !
Moreover if someone knows how to estimate the condition number of the preconditioned system it would be great too (and more accurate)!