Function _check_input_backprop

test/test_models.py:202–228

(model, inputs)

def _check_input_backprop(model, inputs):
    if isinstance(inputs, list):
        requires_grad = list()
        for inp in inputs:
            requires_grad.append(inp.requires_grad)
            inp.requires_grad_(True)
    else:
        requires_grad = inputs.requires_grad
        inputs.requires_grad_(True)

    out = model(inputs)

    if isinstance(out, dict):
        out["out"].sum().backward()
    else:
        if isinstance(out[0], dict):
            out[0]["scores"].sum().backward()
        else:
            out[0].sum().backward()

    if isinstance(inputs, list):
        for i, inp in enumerate(inputs):
            assert inputs[i].grad is not None
            inp.requires_grad_(requires_grad[i])
    else:
        assert inputs.grad is not None
        inputs.requires_grad_(requires_grad)


# If 'unwrapper' is provided it will be called with the script model outputs