Fixing example code for BinaryFocalCrossentropy in losses.py file

The example mentioned for the Keras API binarycrossentropy was failing with the error AttributeError: 'list' object has no attribute 'shape'.

>>> # Example 2: (batch_size = 2, number of samples = 4)
>>> y_true = [[0, 1], [0, 0]]
>>> y_pred = [[-18.6, 0.51], [2.94, -12.8]]
>>> # Using default 'auto'/'sum_over_batch_size' reduction type.
>>> loss = keras.losses.BinaryFocalCrossentropy(
        gamma=3, from_logits=True)
>>> loss(y_true, y_pred)

It works if we change the input from list to arrays.

>>> # Example 2: (batch_size = 2, number of samples = 4)
>>> y_true = np.array([[0, 1], [0, 0]])
>>> y_pred = np.array([[-18.6, 0.51], [2.94, -12.8]])
>>> # Using default 'auto'/'sum_over_batch_size' reduction type.
>>> loss = keras.losses.BinaryFocalCrossentropy(
        gamma=3, from_logits=True)
>>> loss(y_true, y_pred)

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keras-team / keras

Fixing example code for BinaryFocalCrossentropy in losses.py file #20492

Codecov Report