[cherry-pick] modified docs of group_norm and crop_tensor (#20339)

* [cherry-pick] modified doc of group_norm, test=release/1.6, test=document_fix (#20234)

* [cherry-pick] modified doc of crop_tensor, test=release/1.6, test=document_fix (#20203)

Author: zhangting2020

paddle/fluid/API.spec

@@ -188,7 +188,7 @@ paddle.fluid.layers.beam_search (ArgSpec(args=['pre_ids', 'pre_scores', 'ids', '
 paddle.fluid.layers.row_conv (ArgSpec(args=['input', 'future_context_size', 'param_attr', 'act'], varargs=None, keywords=None, defaults=(None, None)), ('document', '1d8a1c8b686b55631ba1b77805e4eacf'))
 paddle.fluid.layers.multiplex (ArgSpec(args=['inputs', 'index'], varargs=None, keywords=None, defaults=None), ('document', '2c4d1ae83da6ed35e3b36ba1b3b51d23'))
 paddle.fluid.layers.layer_norm (ArgSpec(args=['input', 'scale', 'shift', 'begin_norm_axis', 'epsilon', 'param_attr', 'bias_attr', 'act', 'name'], varargs=None, keywords=None, defaults=(True, True, 1, 1e-05, None, None, None, None)), ('document', '79797f827d89ae72c77960e9696883a9'))
-paddle.fluid.layers.group_norm (ArgSpec(args=['input', 'groups', 'epsilon', 'param_attr', 'bias_attr', 'act', 'data_layout', 'name'], varargs=None, keywords=None, defaults=(1e-05, None, None, None, 'NCHW', None)), ('document', '65231cc8281815124934b1439fbb750c'))
+paddle.fluid.layers.group_norm (ArgSpec(args=['input', 'groups', 'epsilon', 'param_attr', 'bias_attr', 'act', 'data_layout', 'name'], varargs=None, keywords=None, defaults=(1e-05, None, None, None, 'NCHW', None)), ('document', '87dd4b818f102bc1a780e1804c28bd38'))
 paddle.fluid.layers.spectral_norm (ArgSpec(args=['weight', 'dim', 'power_iters', 'eps', 'name'], varargs=None, keywords=None, defaults=(0, 1, 1e-12, None)), ('document', '9461e67095a6fc5d568fb2ce8fef66ff'))
 paddle.fluid.layers.softmax_with_cross_entropy (ArgSpec(args=['logits', 'label', 'soft_label', 'ignore_index', 'numeric_stable_mode', 'return_softmax', 'axis'], varargs=None, keywords=None, defaults=(False, -100, True, False, -1)), ('document', '54e1675aa0364f4a78fa72804ec0f413'))
 paddle.fluid.layers.smooth_l1 (ArgSpec(args=['x', 'y', 'inside_weight', 'outside_weight', 'sigma'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'cbe8940643ac80ef75e1abdfbdb09e88'))
@@ -223,7 +223,7 @@ paddle.fluid.layers.relu (ArgSpec(args=['x', 'name'], varargs=None, keywords=Non
 paddle.fluid.layers.selu (ArgSpec(args=['x', 'scale', 'alpha', 'name'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'f93c61f5b0bf933cd425a64dca2c4fdd'))
 paddle.fluid.layers.log (ArgSpec(args=['x', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '02f668664e3bfc4df6c00d7363467140'))
 paddle.fluid.layers.crop (ArgSpec(args=['x', 'shape', 'offsets', 'name'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'ba3621917d5beffd3d022b88fbf6dc46'))
-paddle.fluid.layers.crop_tensor (ArgSpec(args=['x', 'shape', 'offsets', 'name'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'cb855453e3506bf54c5c013616ffddfb'))
+paddle.fluid.layers.crop_tensor (ArgSpec(args=['x', 'shape', 'offsets', 'name'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'd460aaf35afbbeb9beea4789aa6e4343'))
 paddle.fluid.layers.rank_loss (ArgSpec(args=['label', 'left', 'right', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '8eb36596bb43d7a907d3397c7aedbdb3'))
 paddle.fluid.layers.margin_rank_loss (ArgSpec(args=['label', 'left', 'right', 'margin', 'name'], varargs=None, keywords=None, defaults=(0.1, None)), ('document', '6fc86ed23b420c8a0f6c043563cf3937'))
 paddle.fluid.layers.elu (ArgSpec(args=['x', 'alpha', 'name'], varargs=None, keywords=None, defaults=(1.0, None)), ('document', '9af1926c06711eacef9e82d7a9e4d308'))

python/paddle/fluid/layers/nn.py

@@ -4262,30 +4262,39 @@ def group_norm(input,
 
     Refer to `Group Normalization <https://arxiv.org/abs/1803.08494>`_ .
 
-    Args:
-        input(Variable): The input tensor variable.
-        groups(int): The number of groups that divided from channels.
-        epsilon(float): The small value added to the variance to prevent
-            division by zero.
-        param_attr(ParamAttr|None): The parameter attribute for the learnable
-            scale :math:`g`. If it is set to False, no scale will be added to the output units.
-            If it is set to None, the bias is initialized one. Default: None.
-        bias_attr(ParamAttr|None): The parameter attribute for the learnable
-            bias :math:`b`. If it is set to False, no bias will be added to the output units.
-            If it is set to None, the bias is initialized zero. Default: None.
-        act(str): Activation to be applied to the output of group normalizaiton.
-        data_layout(string, default NCHW): NCHW(num_batch, channels, h, w) or NHWC(num_batch, h, w, channels).
-        name (str): The name of this layer. It is optional.
+    Parameters:
+        input(Variable): 4-D Tensor, the data type is float32 or float64.
+        groups(int): The number of groups that divided from channels, the data type
+            is int32.
+        epsilon(float, optional): The small value added to the variance to prevent
+            division by zero, the data type is float32. Default: 1e-05.
+        param_attr(ParamAttr|bool, optional): ParamAttr object that specifies weight parameter
+            attribute. If a bool type, only False is supported, which means there is no weight parameter.
+            Default: None, the default weight parameter attribute is used. For more information, please
+            refer to :ref:`api_guide_ParamAttr` .
+        bias_attr(ParamAttr|bool, optional): ParamAttr object that specifies bias parameter
+            attribute. If a bool type, only False is supported, which means there is no bias parameter.
+            Default: None, the default bias parameter attribute is used. For more information, please
+            refer to :ref:`api_guide_ParamAttr` .
+        act(str, optional): Activation to be applied to the output of group normalizaiton.
+        data_layout(str, optional): The data format of the input and output data. An optional string
+            from: `"NCHW"`, `"NHWC"`. When it is `"NCHW"`, the data is stored in the order of:
+            `[batch_size, channels, height, width]`. Default: "NCHW".
+        name (str, optional): The default value is None. Normally there is no need for user to set this
+            property. For more information, please refer to :ref:`api_guide_Name` .
 
     Returns:
-        Variable: A tensor variable which is the result after applying group normalization on the input.
+        Variable: A 4-D Tensor has same data type and data format with `input`.
+
+    Raises:
+        ValueError: If `data_layout` is neither 'NCHW' nor 'NHWC'.
 
     Examples:
+       .. code-block:: python
 
-        >>> import paddle.fluid as fluid
-        >>> data = fluid.layers.data(name='data', shape=[8, 32, 32],
-        >>>                          dtype='float32')
-        >>> x = fluid.layers.group_norm(input=data, groups=4)
+            import paddle.fluid as fluid
+            data = fluid.data(name='data', shape=[None, 8, 32, 32], dtype='float32')
+            x = fluid.layers.group_norm(input=data, groups=4)
     """
     helper = LayerHelper('group_norm', **locals())
     dtype = helper.input_dtype()
@@ -10206,59 +10215,57 @@ def crop_tensor(x, shape=None, offsets=None, name=None):
 
     .. code-block:: text
 
-        * Case 1:
-            Given
-                X = [[0, 1, 2, 0, 0]
-                     [0, 3, 4, 0, 0]
-                     [0, 0, 0, 0, 0]],
-            and
-                shape = [2, 2],
-                offsets = [0, 1],
-            output is:
+        * Case 1 (input is a 2-D Tensor):
+            Input:
+                X.shape = [3. 5]
+                X.data = [[0, 1, 2, 0, 0],
+                          [0, 3, 4, 0, 0],
+                          [0, 0, 0, 0, 0]]
+            Parameters:
+                shape = [2, 2]
+                offsets = [0, 1]
+            Output:
                 Out = [[1, 2],
-                       [3, 4]].
-        * Case 2:
-            Given
-                X =  [[[0, 1, 2, 3]
-                       [0, 5, 6, 7]
-                       [0, 0, 0, 0]],
-
-                      [[0, 3, 4, 5]
-                       [0, 6, 7, 8]
-                       [0, 0, 0, 0]]].
-            and
-                shape = [2, 2, 3],
-                offsets = [0, 0, 1],
-            output is:
-                Out = [[[1, 2, 3]
+                       [3, 4]]
+        * Case 2 (input is a 3-D Tensor):
+            Input:
+                X.shape = [2, 3, 4]
+                X.data =  [[[0, 1, 2, 3],
+                            [0, 5, 6, 7],
+                            [0, 0, 0, 0]],
+                           [[0, 3, 4, 5],
+                            [0, 6, 7, 8],
+                            [0, 0, 0, 0]]]
+            Parameters:
+                shape = [2, 2, 3]
+                offsets = [0, 0, 1]
+            Output:
+                Out = [[[1, 2, 3],
                         [5, 6, 7]],
-
-                        [[3, 4, 5]
-                         [6, 7, 8]]].
-
-    Args:
-        x (Variable): The input tensor variable.
-        shape (Variable|list|tuple of integer): The output shape is specified
-            by `shape`. It can be a 1-D tensor Variable or a list/tuple. If a 
-            1-D tensor Variable, it's rank must be the same as `x`. If a 
-            list/tuple, it's length must be the same as the rank of `x`. Each 
-            element of list can be an integer or a tensor Variable of shape: [1].
+                       [[3, 4, 5],
+                        [6, 7, 8]]]
+
+    Parameters:
+        x (Variable): 1-D to 6-D Tensor, the data type is float32 or float64.
+        shape (list|tuple|Variable): The output shape is specified
+            by `shape`. Its data type is int32. If a list/tuple, it's length must be
+            the same as the dimension size of `x`. If a Variable, it shoule be a 1-D Tensor.
+            When it is a list, each element can be an integer or a Tensor of shape: [1].
             If Variable contained, it is suitable for the case that the shape may 
             be changed each iteration. Only the first element of list/tuple can be 
-            set to -1, it means that the first dimension of the output is the same 
+            set to -1, it means that the first dimension's size of the output is the same 
             as the input.
-        offsets (Variable|list|tuple of integer|None): Specifies the cropping
-            offsets at each dimension. It can be a 1-D tensor Variable or a list/tuple.
-            If a 1-D tensor Variable, it's rank must be the same as `x`. If a list/tuple, 
-            it's length must be the same as the rank of `x`. Each element of list can be
-            an integer or a tensor Variable of shape: [1]. If Variable contained, it is 
-            suitable for the case that the offsets may be changed each iteration. If None, 
-            the offsets are 0 at each dimension.
-        name(str|None): A name for this layer(optional). If set None, the layer
-                        will be named automatically.
+        offsets (list|tuple|Variable, optional): Specifies the cropping
+            offsets at each dimension. Its data type is int32. If a list/tuple, it's length
+            must be the same as the dimension size of `x`. If a Variable, it shoule be a 1-D
+            Tensor. When it is a list, each element can be an integer or a Tensor of shape: [1].
+            If Variable contained, it is suitable for the case that the offsets may be changed
+            each iteration. Default: None, the offsets are 0 at each dimension.
+        name(str, optional): The default value is None. Normally there is no need for user to set
+            this property. For more information, please refer to :ref:`api_guide_Name` .
 
     Returns:
-        Variable: The cropped tensor variable.
+        Variable: The cropped Tensor has same data type with `x`.
 
     Raises:
         ValueError: If shape is not a list, tuple or Variable.
@@ -10269,31 +10276,31 @@ def crop_tensor(x, shape=None, offsets=None, name=None):
         .. code-block:: python
 
             import paddle.fluid as fluid
-            x = fluid.layers.data(name="x", shape=[3, 5], dtype="float32")
+            x = fluid.data(name="x", shape=[None, 3, 5], dtype="float32")
             # x.shape = [-1, 3, 5], where -1 indicates batch size, and it will get the exact value in runtime.
 
-            # shape is a 1-D tensor variable
-            crop_shape = fluid.layers.data(name="crop_shape", shape=[3], dtype="int32", append_batch_size=False)
+            # shape is a 1-D Tensor
+            crop_shape = fluid.data(name="crop_shape", shape=[3], dtype="int32")
             crop0 = fluid.layers.crop_tensor(x, shape=crop_shape)
             # crop0.shape = [-1, -1, -1], it means crop0.shape[0] = x.shape[0] in runtime.
 
             # or shape is a list in which each element is a constant
             crop1 = fluid.layers.crop_tensor(x, shape=[-1, 2, 3])
             # crop1.shape = [-1, 2, 3]
 
-            # or shape is a list in which each element is a constant or variable
-            y = fluid.layers.data(name="y", shape=[3, 8, 8], dtype="float32")
-            dim1 = fluid.layers.data(name="dim1", shape=[1], dtype="int32", append_batch_size=False)
-            crop2 = fluid.layers.crop_tensor(y, shape=[-1, 3, dim1, 4])
-            # crop2.shape = [-1, 3, -1, 4]
+            # or shape is a list in which each element is a constant or Variable
+            y = fluid.data(name="y", shape=[3, 8, 8], dtype="float32")
+            dim1 = fluid.data(name="dim1", shape=[1], dtype="int32")
+            crop2 = fluid.layers.crop_tensor(y, shape=[3, dim1, 4])
+            # crop2.shape = [3, -1, 4]
 
-            # offsets is a 1-D tensor variable
-            crop_offsets = fluid.layers.data(name="crop_offsets", shape=[3], dtype="int32", append_batch_size=False)
+            # offsets is a 1-D Tensor
+            crop_offsets = fluid.data(name="crop_offsets", shape=[3], dtype="int32")
             crop3 = fluid.layers.crop_tensor(x, shape=[-1, 2, 3], offsets=crop_offsets)
             # crop3.shape = [-1, 2, 3]
 
-            # offsets is a list in which each element is a constant or variable
-            offsets_var =  fluid.layers.data(name="dim1", shape=[1], dtype="int32", append_batch_size=False)
+            # offsets is a list in which each element is a constant or Variable
+            offsets_var =  fluid.data(name="dim1", shape=[1], dtype="int32")
             crop4 = fluid.layers.crop_tensor(x, shape=[-1, 2, 3], offsets=[0, 1, offsets_var])
             # crop4.shape = [-1, 2, 3]