Function decode

nodedb-array/src/coord/zorder.rs:28–39

Inverse of [`encode`].

(idx: u64, n: usize, bits: u32)

/// Inverse of [`encode`].
pub fn decode(idx: u64, n: usize, bits: u32) -> ArrayResult<Vec<u64>> {
    check_shape(n, bits)?;
    let mut out = vec![0u64; n];
    for b in (0..bits).rev() {
        for (i, slot) in out.iter_mut().enumerate().take(n) {
            let shift = b * n as u32 + (n as u32 - 1 - i as u32);
            let bit = (idx >> shift) & 1;
            *slot = (*slot << 1) | bit;
        }
    }
    Ok(out)
}

fn check_shape(n: usize, bits: u32) -> ArrayResult<()> {
    if n > MAX_DIMS {