add optional and union cases

0515436f · BO ZHANG · c005808c · 0515436f
Commit 0515436f authored Sep 16, 2023 by BO ZHANG 🏀
--- a/docs/source/demo_type_annotation.ipynb
+++ b/docs/source/demo_type_annotation.ipynb
@@ -67,6 +67,28 @@
    "- Any表示任意类型"
   ]
  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "3b323abd-7689-4abd-aa02-049b1de7bfcb",
+   "metadata": {},
+   "outputs": [
+    {
+     "ename": "NameError",
+     "evalue": "name 'Optional' is not defined",
+     "output_type": "error",
+     "traceback": [
+      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
+      "\u001b[0;31mNameError\u001b[0m                                 Traceback (most recent call last)",
+      "Cell \u001b[0;32mIn[3], line 1\u001b[0m\n\u001b[0;32m----> 1\u001b[0m x0: Optional[\u001b[38;5;28mint\u001b[39m] \u001b[38;5;241m=\u001b[39m \u001b[38;5;28;01mNone\u001b[39;00m\n",
+      "\u001b[0;31mNameError\u001b[0m: name 'Optional' is not defined"
+     ]
+    }
+   ],
+   "source": [
+    "fx0: Optional[int] = None"
+   ]
+  },
  {
   "cell_type": "markdown",
   "id": "4906826b-2817-4a5b-b3ac-a993fa96b315",
@@ -80,7 +102,7 @@
  },
  {
   "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": null,
   "id": "d93f8b14-5f88-4579-a671-1693d04ce144",
   "metadata": {},
   "outputs": [],
@@ -92,7 +114,7 @@
  },
  {
   "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": null,
   "id": "14b83562-b6c6-4873-8936-ad9d0c9c0e6f",
   "metadata": {},
   "outputs": [],

 %% Cell type:markdown id:63584611-70c6-45e4-acfb-9bda5204fda0 tags:

 # How to do Python type annotation

 %% Cell type:markdown id:7cc03b6e-5bc4-47e4-b42c-3a22eb11539b tags:

 ## built-in types

 %% Cell type:code id:bfaf414a-40f8-4830-8be4-65f43a03d513 tags:

 ``` python
 a: int = 8 # 整数型标注
 b: float = 1.23 # 浮点型标注
 c: bool = True # 布尔型标注
 d: tuple = (1, 2) # 元组型标注
 e: tuple[int, float] = (1, 2.34) # 限定类型和元素个数的元组标注
 f: tuple[int, ...] = (1, 2, 3, 4, 5) # 限定类型但不定元素个数的元组型标注
 g: list = [1, 2, 3] # 一般的列表型标注
 h: list[int] = [1, 2, 3] # 对列表型来说不需要标元素个数，但可以明确要求元素类型
 ```

 %% Cell type:markdown id:ba646556-0bfa-4a8f-8767-9d76e5c44592 tags:

 ## `typing` 模块
 对于一些内建类型来说是可以直接用内建类型来标注的，例如以下两句是相等的

 %% Cell type:code id:8759dc5b-01e9-4583-ab27-114ea87315db tags:

 ``` python
 l1: list[int] = [1, 2, 3]

 from typing import List
 l2: List[int] = [1, 2, 3]
 ```

 %% Cell type:markdown id:8f2203cb-8e94-406e-b445-809d04f85e26 tags:

 ## Union, Optional和Any

 - Union表示并集，Union[float, int]表示可以是float也可以是int
 - Optional表示可选，Optional[int]表示可以是None也可以是int
 - Any表示任意类型

+%% Cell type:code id:3b323abd-7689-4abd-aa02-049b1de7bfcb tags:
+
+``` python
+fx0: Optional[int] = None
+```
+
+%% Output
+
+    ---------------------------------------------------------------------------
+    NameError                                 Traceback (most recent call last)
+Cell     In[3], line 1
+    ----> 1 x0: Optional[int] = None
+    NameError: name 'Optional' is not defined
+
 %% Cell type:markdown id:4906826b-2817-4a5b-b3ac-a993fa96b315 tags:

 ## numpy.typing
 我们经常会用到numpy.ndarray进行科学计算，可以有以下几种标注方式:

 1. 直接用np.ndarray进行标注, 此时不限定类型(dtype)

 %% Cell type:code id:d93f8b14-5f88-4579-a671-1693d04ce144 tags:

 ``` python
 import numpy as np

 x1: np.ndarray = np.arange(10)
 ```

 %% Cell type:code id:14b83562-b6c6-4873-8936-ad9d0c9c0e6f tags:

 ``` python
 import numpy.typing as npt

 x2: npt.NDArray = np.arange(10, dtype=float)
 x3: npt.NDArray[np.int_] = np.arange(10, dtype=int)
 x4: npt.NDArray[np.float_] = np.arange(10, dtype=float)
 x5: npt.NDArray[np.float32] = np.arange(10, dtype=np.float32)
 x6: npt.NDArray[np.bool_] = np.ones(10, dtype=bool)
 x7: npt.NDArray[np.complex_] = np.ones(10, dtype=np.complex_)
 ```

 %% Cell type:code id:cc6abe41-f8a1-4c9d-8deb-ba7dad66780f tags:

 ``` python
 ```