Esempio n. 1
0
def test_integration_precision_recall_curve_with_activated_output_transform():
    np.random.seed(1)
    size = 100
    np_y_pred = np.random.rand(size, 1)
    np_y_pred_sigmoid = torch.sigmoid(torch.from_numpy(np_y_pred)).numpy()
    np_y = np.zeros((size,), dtype=np.long)
    np_y[size // 2 :] = 1
    np.random.shuffle(np_y)

    sk_precision, sk_recall, sk_thresholds = precision_recall_curve(np_y, np_y_pred_sigmoid)

    batch_size = 10

    def update_fn(engine, batch):
        idx = (engine.state.iteration - 1) * batch_size
        y_true_batch = np_y[idx : idx + batch_size]
        y_pred_batch = np_y_pred[idx : idx + batch_size]
        return idx, torch.from_numpy(y_pred_batch), torch.from_numpy(y_true_batch)

    engine = Engine(update_fn)

    precision_recall_curve_metric = PrecisionRecallCurve(output_transform=lambda x: (torch.sigmoid(x[1]), x[2]))
    precision_recall_curve_metric.attach(engine, "precision_recall_curve")

    data = list(range(size // batch_size))
    precision, recall, thresholds = engine.run(data, max_epochs=1).metrics["precision_recall_curve"]

    assert np.array_equal(precision, sk_precision)
    assert np.array_equal(recall, sk_recall)
    # assert thresholds almost equal, due to numpy->torch->numpy conversion
    np.testing.assert_array_almost_equal(thresholds, sk_thresholds)
    def _test(n_epochs, metric_device):
        metric_device = torch.device(metric_device)
        n_iters = 80
        size = 151
        y_true = torch.randint(0, 2, (size,)).to(device)
        y_preds = torch.randint(0, 2, (size,)).to(device)

        def update(engine, i):
            return (
                y_preds[i * size : (i + 1) * size],
                y_true[i * size : (i + 1) * size],
            )

        engine = Engine(update)

        prc = PrecisionRecallCurve(device=metric_device)
        prc.attach(engine, "prc")

        data = list(range(n_iters))
        engine.run(data=data, max_epochs=n_epochs)

        assert "prc" in engine.state.metrics

        precision, recall, thresholds = engine.state.metrics["prc"]

        np_y_true = y_true.cpu().numpy().ravel()
        np_y_preds = y_preds.cpu().numpy().ravel()

        sk_precision, sk_recall, sk_thresholds = precision_recall_curve(np_y_true, np_y_preds)

        assert precision.shape == sk_precision.shape
        assert recall.shape == sk_recall.shape
        assert thresholds.shape == sk_thresholds.shape
        assert pytest.approx(precision.cpu().numpy()) == sk_precision
        assert pytest.approx(recall.cpu().numpy()) == sk_recall
        assert pytest.approx(thresholds.cpu().numpy()) == sk_thresholds