It is possible to call SuperLU 3.0 (http://crd.lbl.gov/verb~xiaoye/SuperLU/) from Gmm++. The following function defined in the file gmm/gmm_superlu_interface.h is available:
SuperLU_solve(A, X, B, condest, permc_spec = 1)
solves the system AX = B where A is a sparse matrix of base type float, double, std::complex<float>, or std::complex<double>. permc_spec should be 0, 1 or 2 for respectively use the natural ordering, use minimum degree ordering on structure of A'A or use minimum degree ordering on structure of A'+A (1 is the default value), condest should be a reference on a double, it returns an estimate of the condition number of the matrix A.
To use these functions, you need to install SuperLU and compile your code with the additional options:
g++ ... -DGMM_USES_SUPERLU (dir_of_superlu)/superlu.a -lblas -I(dir_of_superlu)
Some other functionalities of SuperLU can be interfaced.