modify

08.functions.md

@@ -8,14 +8,22 @@
 
 案例（保存为 `function1.py`）：
 
-```text
-{% include "./programs/function1.py" %}
+```python
+def say_hello():
+    # 该块属于这一函数
+    print('hello world')
+# 函数结束
+
+say_hello()  # 调用函数
+say_hello()  # 再次调用函数
 ```
 
 输出：
 
 ```text
-{% include "./programs/function1.txt" %}
+$ python function1.py
+hello world
+hello world
 ```
 
 **它是如何工作的**
@@ -32,14 +40,31 @@
 
 案例（保存为 `function_param.py`）：
 
-```text
-{% include "./programs/function_param.py" %}
+```python
+def print_max(a, b):
+    if a > b:
+        print(a, 'is maximum')
+    elif a == b:
+        print(a, 'is equal to', b)
+    else:
+        print(b, 'is maximum')
+
+# 直接传递字面值
+print_max(3, 4)
+
+x = 5
+y = 7
+
+# 以参数的形式传递变量
+print_max(x, y)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_param.txt" %}
+$ python function_param.py
+4 is maximum
+7 is maximum
 ```
 
 **它是如何工作的**
@@ -54,14 +79,27 @@
 
 案例（保存为 `function_local.py`）：
 
-```text
-{% include "./programs/function_local.py" %}
+```python
+x = 50
+
+
+def func(x):
+    print('x is', x)
+    x = 2
+    print('Changed local x to', x)
+
+
+func(x)
+print('x is still', x)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_local.txt" %}
+$ python function_local.py
+x is 50
+Changed local x to 2
+x is still 50
 ```
 
 **它是如何工作的**
@@ -80,14 +118,29 @@
 
 案例（保存为 `function_global.py`）：
 
-```text
-{% include "./programs/function_global.py" %}
+```python
+x = 50
+
+
+def func():
+    global x
+
+    print('x is', x)
+    x = 2
+    print('Changed global x to', x)
+
+
+func()
+print('Value of x is', x)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_global.txt" %}
+$ python function_global.py
+x is 50
+Changed global x to 2
+Value of x is 2
 ```
 
 **它是如何工作的**
@@ -104,14 +157,20 @@
 
 案例（保存为 `function_default.py`）：
 
-```text
-{% include "./programs/function_default.py" %}
+```python
+def say(message, times=1):
+    print(message * times)
+
+say('Hello')
+say('World', 5)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_default.txt" %}
+$ python function_default.py
+Hello
+WorldWorldWorldWorldWorld
 ```
 
 **它是如何工作的**
@@ -134,14 +193,22 @@
 
 案例（保存为 `function_keyword.py`）：
 
-```text
-{% include "./programs/function_keyword.py" %}
+```python
+def func(a, b=5, c=10):
+    print('a is', a, 'and b is', b, 'and c is', c)
+
+func(3, 7)
+func(25, c=24)
+func(c=50, a=100)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_keyword.txt" %}
+$ python function_keyword.py
+a is 3 and b is 7 and c is 10
+a is 25 and b is 5 and c is 24
+a is 100 and b is 5 and c is 50
 ```
 
 **它是如何工作的**
@@ -158,14 +225,33 @@
 
 有时你可能想定义的函数里面能够有_任意_数量的变量，也就是参数数量是可变的，这可以通过使用星号来实现（将下方案例保存为 `function_varargs.py`）：
 
-```text
-{% include "./programs/function_varargs.py" %}
+```python
+def total(a=5, *numbers, **phonebook):
+    print('a', a)
+
+    #遍历元组中的所有项目
+    for single_item in numbers:
+        print('single_item', single_item)
+
+    #遍历字典中的所有项目
+    for first_part, second_part in phonebook.items():
+        print(first_part,second_part)
+
+print(total(10,1,2,3,Jack=1123,John=2231,Inge=1560))
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_varargs.txt" %}
+$ python function_varargs.py
+a 10
+single_item 1
+single_item 2
+single_item 3
+Inge 1560
+John 2231
+Jack 1123
+None
 ```
 
 **它是如何工作的**
@@ -182,14 +268,23 @@
 
 案例（保存为 `function_return.py`）：
 
-```text
-{% include "./programs/function_return.py" %}
+```python
+def maximum(x, y):
+    if x > y:
+        return x
+    elif x == y:
+        return 'The numbers are equal'
+    else:
+        return y
+
+print(maximum(2, 3))
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_return.txt" %}
+$ python function_return.py
+3
 ```
 
 _它是如何工作的_
@@ -215,14 +310,32 @@ Python 有一个甚是优美的功能称作_文档字符串（Documentation Stri
 
 案例（保存为 `function_docstring.py`）：
 
-```text
-{% include "./programs/function_docstring.py" %}
+```python
+def print_max(x, y):
+    '''打印两个数值中的最大数。
+
+    这两个数都应该是整数'''
+    # 如果可能，将其转换至整数类型
+    x = int(x)
+    y = int(y)
+
+    if x > y:
+        print(x, 'is maximum')
+    else:
+        print(y, 'is maximum')
+
+print_max(3, 5)
+print(print_max.__doc__)
 ```
 
 输出：
 
 ```text
-{% include "./programs/function_docstring.txt" %}
+$ python function_docstring.py
+5 is maximum
+打印两个数值中的最大数。
+
+    这两个数都应该是整数
 ```
 
 **它是如何工作的**