add illustration for reshape API

python/paddle/tensor/manipulation.py

@@ -4345,11 +4345,16 @@ def reshape(x, shape, name=None):
 
         - 3. Given a 3-D tensor x with a shape [2, 4, 6], and the target shape is [-1, 0, 3, 2], the reshape operator will transform x into a 4-D tensor with shape [2, 4, 3, 2] and leaving x's data unchanged. In this case, besides -1, 0 means the actual dimension value is going to be copied from the corresponding dimension of x.
 
+    The following figure illustrates the first example -- a 3D tensor of shape [2, 4, 6] is transformed into a 2D tensor of shape [6, 8], during which the order and values of the elements in the tensor remain unchanged. The elements in the two subdiagrams correspond to each other, clearly demonstrating how the reshape API works.
+
+    .. image:: ../../../../docs/docs/images/api_legend/reshape.png
+        :alt: legend of reshape API
+
     Args:
         x (Tensor): An N-D Tensor. The data type is ``float16``, ``float32``, ``float64``, ``int16``, ``int32``, ``int64``, ``int8``, ``uint8``, ``complex64``, ``complex128``, ``bfloat16`` or ``bool``.
         shape (list|tuple|Tensor): Define the target shape. At most one dimension of the target shape can be -1.
                         The data type is ``int32`` . If ``shape`` is a list or tuple, each element of it should be integer or Tensor with shape [].
-                        If ``shape`` is an Tensor, it should be an 1-D Tensor .
+                        If ``shape`` is a Tensor, it should be an 1-D Tensor .
         name (str, optional): Name for the operation (optional, default is None). For more information, please refer to :ref:`api_guide_Name`.
 
     Returns: