blas_sys::c::cblas_dgemv

pub unsafe extern fn cblas_dgemv(layout: CBLAS_LAYOUT, transa: CBLAS_TRANSPOSE, m: c_int, n: c_int, alpha: c_double, a: *const c_double, lda: c_int, x: *const c_double, incx: c_int, beta: c_double, y: *mut c_double, incy: c_int)