lapack
pub unsafe fn dsgesv( n: i32, nrhs: i32, a: &mut [f64], lda: i32, ipiv: &mut [i32], b: &[f64], ldb: i32, x: &mut [f64], ldx: i32, work: &mut [f64], swork: &mut [f32], iter: &mut i32, info: &mut i32)