我試過用Rust的LAPACK綁定,當我找到一些我找不到的語法時。函數參數旁邊的兩個單引號括起來的字母是什麼意思?
從https://github.com/stainless-steel/lapack的示例代碼:
let n = 3;
let mut a = vec![3.0, 1.0, 1.0, 1.0, 3.0, 1.0, 1.0, 1.0, 3.0];
let mut w = vec![0.0; n];
let mut work = vec![0.0; 4 * n];
let lwork = 4 * n as isize;
let mut info = 0;
lapack::dsyev(b'V', b'U', n, &mut a, n, &mut w, &mut work, lwork, &mut info);
for (one, another) in w.iter().zip(&[2.0, 2.0, 5.0]) {
assert!((one - another).abs() < 1e-14);
}
是什麼b'V '和b'U'是什麼意思?