Intel
DSYSV Example
The routine solves the real system of linear equations for X: A*X = B
http://software.intel.com/sites/products/documentation/hpc/mkl/lapack/mkl_lapack_examples/dsysv.htm#top
DSYSV computes the solution to a real system of linear equations
A * X = B,
where A is an N-by-N symmetric matrix and X and B are N-by- NRHS matrices.
http://www.physics.orst.edu/~rubin/nacphy/lapack/routines/dsysv.html