Function GxB_Matrix_select 

pub unsafe extern "C" fn GxB_Matrix_select(
    C: GrB_Matrix,
    Mask: GrB_Matrix,
    accum: GrB_BinaryOp,
    op: GxB_SelectOp,
    A: GrB_Matrix,
    Thunk: GrB_Scalar,
    desc: GrB_Descriptor,
) -> GrB_Info