message: Add example code for tf.math.scalar_mul
diff: @@ -593,9 +593,15 @@ def _neg(x, name=None):
  def scalar_mul(scalar, x, name=None):
  """Multiplies a scalar times a `Tensor` or `IndexedSlices` object.
  - Intended for use in gradient code which might deal with `IndexedSlices`
  - objects, which are easy to multiply by a scalar but more expensive to
  - multiply with arbitrary tensors.
  + This is a special case of `tf.math.multiply`, where the first value must be a
  + `scalar`. Unlike the general form of `tf.math.multiply`, this is operation is
  + guaranteed to be efficient for `tf.IndexedSlices`.
  +
  + >>> x = tf.reshape(tf.range(30, dtype=tf.float32), [10, 3])
  + >>> with tf.GradientTape() as g:
  + ... g.watch(x)
  + ... y = tf.gather(x, [1, 2]) # IndexedSlices
  + ... z = tf.math.scalar_mul(10.0, y)
  Args:
  scalar: A 0-D scalar `Tensor`. Must have known shape.
  