Function GrB_Col_extract 

pub unsafe extern "C" fn GrB_Col_extract(
    w: GrB_Vector,
    mask: GrB_Vector,
    accum: GrB_BinaryOp,
    A: GrB_Matrix,
    I: *const GrB_Index,
    ni: GrB_Index,
    j: GrB_Index,
    desc: GrB_Descriptor,
) -> GrB_Info