Beispiel #1
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def test_model_backward(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        channel_axis=1)

    test_image = np.random.rand(channels, 5, 5).astype(np.float32)
    test_grad_pre = np.random.rand(num_classes).astype(np.float32)

    test_grad = model.backward_one(test_grad_pre, test_image)
    assert test_grad.shape == test_image.shape

    manual_grad = np.repeat(np.repeat(
        (test_grad_pre / 25.).reshape((-1, 1, 1)),
        5, axis=1), 5, axis=2)

    np.testing.assert_almost_equal(
        test_grad,
        manual_grad)
Beispiel #2
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def test_model_backward(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        channel_axis=1)

    test_image = np.random.rand(channels, 5, 5).astype(np.float32)
    test_grad_pre = np.random.rand(num_classes).astype(np.float32)

    test_grad = model.backward(test_grad_pre, test_image)
    assert test_grad.shape == test_image.shape

    manual_grad = np.repeat(np.repeat(
        (test_grad_pre / 25.).reshape((-1, 1, 1)),
        5, axis=1), 5, axis=2)

    np.testing.assert_almost_equal(
        test_grad,
        manual_grad)
Beispiel #3
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def test_model_forward_gradient(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable("images")
    logits = mean_brightness_net(images)

    preprocessing = (
        np.arange(num_classes)[:, None, None],
        np.random.uniform(size=(channels, 5, 5)) + 1,
    )

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        preprocessing=preprocessing,
        channel_axis=1,
    )

    test_images = np.random.rand(5, channels, 5, 5).astype(np.float32)
    test_labels = [7] * 5

    epsilon = 1e-2
    _, g1 = model.forward_and_gradient(test_images, test_labels)
    l1 = model._loss_fn(test_images - epsilon / 2 * g1, test_labels)
    l2 = model._loss_fn(test_images + epsilon / 2 * g1, test_labels)

    assert np.all(1e4 * (l2 - l1) > 1)

    # make sure that gradient is numerically correct
    np.testing.assert_array_almost_equal(
        1e4 * (l2 - l1),
        1e4 * epsilon *
        (np.linalg.norm(g1.reshape(len(g1), -1), axis=(-1))**2).sum(),
        decimal=1,
    )
Beispiel #4
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def test_model_gradient(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    preprocessing = (np.arange(num_classes)[:, None, None],
                     np.random.uniform(size=(channels, 5, 5)) + 1)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        preprocessing=preprocessing,
        channel_axis=1)

    test_images = np.random.rand(2, channels, 5, 5).astype(np.float32)
    test_image = test_images[0]
    test_label = 7

    epsilon = 1e-2
    _, g1 = model.predictions_and_gradient(test_image, test_label)
    l1 = model._loss_fn(test_image - epsilon / 2 * g1, test_label)
    l2 = model._loss_fn(test_image + epsilon / 2 * g1, test_label)

    assert 1e4 * (l2 - l1) > 1

    # make sure that gradient is numerically correct
    np.testing.assert_array_almost_equal(
        1e4 * (l2 - l1),
        1e4 * epsilon * np.linalg.norm(g1)**2,
        decimal=1)
Beispiel #5
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def test_model_gradient(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    preprocessing = (np.arange(num_classes)[:, None, None],
                     np.random.uniform(size=(channels, 5, 5)) + 1)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        preprocessing=preprocessing,
        channel_axis=1)

    test_images = np.random.rand(2, channels, 5, 5).astype(np.float32)
    test_image = test_images[0]
    test_label = 7

    epsilon = 1e-2
    _, g1 = model.forward_and_gradient_one(test_image, test_label)
    l1 = model._loss_fn(test_image - epsilon / 2 * g1, test_label)
    l2 = model._loss_fn(test_image + epsilon / 2 * g1, test_label)

    assert 1e4 * (l2 - l1) > 1

    # make sure that gradient is numerically correct
    np.testing.assert_array_almost_equal(
        1e4 * (l2 - l1),
        1e4 * epsilon * np.linalg.norm(g1)**2,
        decimal=1)
Beispiel #6
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def test_model(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        channel_axis=1)

    test_images = np.random.rand(2, channels, 5, 5).astype(np.float32)
    test_label = 7

    # Tests
    assert model.forward(test_images).shape \
        == (2, num_classes)

    test_logits = model.forward_one(test_images[0])
    assert test_logits.shape == (num_classes,)

    test_gradient = model.gradient_one(test_images[0], test_label)
    assert test_gradient.shape == test_images[0].shape

    np.testing.assert_almost_equal(
        model.forward_and_gradient_one(test_images[0], test_label)[0],
        test_logits)
    np.testing.assert_almost_equal(
        model.forward_and_gradient_one(test_images[0], test_label)[1],
        test_gradient)

    assert model.num_classes() == num_classes
Beispiel #7
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def test_model(num_classes):
    bounds = (0, 255)
    channels = num_classes

    def mean_brightness_net(images):
        logits = mx.symbol.mean(images, axis=(2, 3))
        return logits

    images = mx.symbol.Variable('images')
    logits = mean_brightness_net(images)

    model = MXNetModel(
        images,
        logits,
        {},
        ctx=mx.cpu(),
        num_classes=num_classes,
        bounds=bounds,
        channel_axis=1)

    test_images = np.random.rand(2, channels, 5, 5).astype(np.float32)
    test_label = 7

    # Tests
    assert model.batch_predictions(test_images).shape \
        == (2, num_classes)

    test_logits = model.predictions(test_images[0])
    assert test_logits.shape == (num_classes,)

    test_gradient = model.gradient(test_images[0], test_label)
    assert test_gradient.shape == test_images[0].shape

    np.testing.assert_almost_equal(
        model.predictions_and_gradient(test_images[0], test_label)[0],
        test_logits)
    np.testing.assert_almost_equal(
        model.predictions_and_gradient(test_images[0], test_label)[1],
        test_gradient)

    assert model.num_classes() == num_classes