def unpack()

in diffq/torch_pack.py [0:0]

• 12 lines of code
• 4 McCabe index (conditional complexity)

def unpack(packed: torch.Tensor, length: tp.Optional[int] = None):
    """Opposite of `pack`. You might need to specify the original length."""
    storage_size = _storage_size(packed.dtype)
    nbits, groups = packed.shape
    out = torch.zeros(storage_size, groups, dtype=torch.int16, device=packed.device)
    for in_bit in range(storage_size):
        for out_bit in range(nbits):
            bit_value = (packed[out_bit, :] >> in_bit) & 1
            out[in_bit, :] = out[in_bit, :] | (bit_value.to(out) << out_bit)
    out = out.view(-1)
    if length is not None:
        out = out[:length]
    return out