Add documentation clarifying the differences between tf.fill and tf.constant.

PiperOrigin-RevId: 208998330

1 files changed, 11 insertions, 0 deletions

diff --git a/tensorflow/python/framework/constant_op.py b/tensorflow/python/framework/constant_op.py
index b3eb57d067..8fab6528e7 100644
--- a/tensorflow/python/framework/constant_op.py
+++ b/tensorflow/python/framework/constant_op.py
@@ -145,6 +145,17 @@ def constant(value, dtype=None, shape=None, name="Const", verify_shape=False):
                                                [-1. -1. -1.]]
   ```
 
+  `tf.constant` differs from `tf.fill` in a few ways:
+
+  *   `tf.constant` supports arbitrary constants, not just uniform scalar
+      Tensors like `tf.fill`.
+  *   `tf.constant` creates a `Const` node in the computation graph with the
+      exact value at graph construction time. On the other hand, `tf.fill`
+      creates an Op in the graph that is expanded at runtime.
+  *   Because `tf.constant` only embeds constant values in the graph, it does
+      not support dynamic shapes based on other runtime Tensors, whereas
+      `tf.fill` does.
+
   Args:
     value:          A constant value (or list) of output type `dtype`.