Dear all,

I am trying to solve a matrix of "mtype = 13", however, by the parameters given in example code, I can't get a good solution. For a case with size about100,000, the residual error ||A*x-b||/||b|| is larger than 1.e-4 which is not acceptable, where ||b||>1. Could anyone tell me how to set the parameters to get a better solution (for real value matrix, the residual error could reach to 1.e-10~1.e-13)?

Thanks,

Zhanghong Tang