Function sparseCategoricalCrossentropy

tfjs-layers/src/losses.ts:136–148

(
    target: Tensor, output: Tensor, fromLogits = false)

 *   a tensor of logits.
 */
export function sparseCategoricalCrossentropy(
    target: Tensor, output: Tensor, fromLogits = false): Tensor {
  return tidy(() => {
    const flatTarget =
        tfc.cast(tfc.floor(K.flatten(target)), 'int32') as Tensor1D;
    output = tfc.clipByValue(output, epsilon(), 1 - epsilon());
    const outputShape = output.shape;
    const oneHotTarget = tfc.reshape(
        tfc.oneHot(flatTarget, outputShape[outputShape.length - 1]),
        outputShape);
    return categoricalCrossentropy(oneHotTarget, output, fromLogits);
  });
}

/**
 * From TensorFlow's implementation in nn_impl.py: