fixed bug for split (#694)

docs/pytorch_project_convertor/API_docs/ops/README.md

@@ -28,7 +28,7 @@
 | 23   | [torch.narrow](https://pytorch.org/docs/stable/generated/torch.narrow.html?highlight=narrow#torch.narrow) | [paddle.slice](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/slice_cn.html#slice) | [差异对比](https://github.com/PaddlePaddle/X2Paddle/tree/develop/docs/pytorch_project_convertor/API_docs/ops/torch.narrow.md)                              |
 | 24   | [torch.nonzero](https://pytorch.org/docs/stable/generated/torch.nonzero.html?highlight=nonzero#torch.nonzero) | [paddle.nonzero](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/nonzero_cn.html#nonzero) | 功能一致，参数名不一致                                       |
 | 25   | [torch.reshape](https://pytorch.org/docs/stable/generated/torch.reshape.html?highlight=reshape#torch.reshape) | [paddle.reshape](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/reshape_cn.html#reshape) | 功能一致，参数名不一致                                       |
-| 26   | [torch.split](https://pytorch.org/docs/stable/generated/torch.split.html?highlight=split#torch.split) | [paddle.split](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/split_cn.html#split) | 功能一致，参数名不一致                                       |
+| 26   | [torch.split](https://pytorch.org/docs/stable/generated/torch.split.html?highlight=split#torch.split) | [paddle.split](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/split_cn.html#split) | [差异对比](https://github.com/PaddlePaddle/X2Paddle/tree/develop/docs/pytorch_project_convertor/API_docs/ops/torch.split.md)                                       |
 | 27   | [torch.squeeze](https://pytorch.org/docs/stable/generated/torch.squeeze.html?highlight=squeeze#torch.squeeze) | [paddle.squeeze](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/squeeze_cn.html#squeeze) | 功能一致，参数名不一致                                       |
 | 28   | [torch.stack](https://pytorch.org/docs/stable/generated/torch.stack.html?highlight=stack#torch.stack) | [paddle.stack](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/stack_cn.html#stack) | 功能一致，参数名不一致                                       |
 | 29   | [torch.t](https://pytorch.org/docs/stable/generated/torch.t.html) | [paddle.t](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/t_cn.html#t) | 功能一致，参数名不一致                                       |

docs/pytorch_project_convertor/API_docs/ops/torch.split.md

+## torch.split
+### [torch.split](https://pytorch.org/docs/stable/generated/torch.split.html?highlight=torch%20split#torch.split)
+
+```python
+torch.split(tensor,
+            split_size_or_sections,
+            dim=0)
+```
+
+### [paddle.split](https://www.paddlepaddle.org.cn/documentation/docs/zh/api/paddle/split_cn.html#split)
+
+```python
+paddle.split(x,
+             num_or_sections,
+             axis=0,
+             name=None)
+```
+
+### 参数差异
+| PyTorch       | PaddlePaddle | 备注                                                   |
+| ------------- | ------------ | ------------------------------------------------------ |
+| tensor        | x        | 表示输入Tensor。                                     |
+| split_size_or_sections           | num_or_sections            | 当类型为int时，torch表示单个块大小，paddle表示结果有多少个块 |
+| dim        | axis            | 表示需要分割的维度。                   |
+
+
+### 功能差异
+
+#### 使用方式
+***PyTorch***：第二个参数split_size_or_sections类型为int或者list(int)。  
+***PaddlePaddle***：第二个参数num_or_sections类型为int、list(int)或者tuple(int)。
+
+
+### 代码示例
+``` python
+# PyTorch示例：
+a = torch.arange(10).reshape(5,2)
+# 输出
+# tensor([[0, 1],
+#         [2, 3],
+#         [4, 5],
+#         [6, 7],
+#         [8, 9]])
+torch.split(a, 2, 1)
+# 输出
+# (tensor([[0, 1],
+#         [2, 3],
+#         [4, 5],
+#         [6, 7],
+#         [8, 9]]),)
+```
+
+``` python
+# PaddlePaddle示例：
+b = paddle.arange(10).reshape([5,2])
+# 输出
+# Tensor(shape=[5, 2], dtype=int64, place=CPUPlace, stop_gradient=True,
+#        [[0, 1],
+#         [2, 3],
+#         [4, 5],
+#         [6, 7],
+#         [8, 9]])
+paddle.split(b, 2, 1)
+# 输出
+# [Tensor(shape=[5, 1], dtype=int64, place=CPUPlace, stop_gradient=True,
+#        [[0],
+#         [2],
+#         [4],
+#         [6],
+#         [8]]), Tensor(shape=[5, 1], dtype=int64, place=CPUPlace, stop_gradient=True,
+#        [[1],
+#         [3],
+#         [5],
+#         [7],
+#         [9]])]
+```