2020-10-19 21:08:55

docs/da/071.md

@@ -10,7 +10,7 @@
 
 In [1]:
 
-```
+```py
 def square(x):
     """Square of x."""
     return x*x
@@ -25,7 +25,7 @@ def cube(x):
 
 In [2]:
 
-```
+```py
 funcs = {
     'square': square,
     'cube': cube,
@@ -37,7 +37,7 @@ funcs = {
 
 In [3]:
 
-```
+```py
 x = 2
 
 print square(x)
@@ -48,7 +48,7 @@ for func in sorted(funcs):
 
 ```
 
-```
+```py
 4
 8
 cube 8
@@ -62,7 +62,7 @@ square 4
 
 `Python` 中的函数传递方式是 `call by reference` 即引用传递，例如，对于这样的用法：
 
-```
+```py
 x = [10, 11, 12]
 f(x) 
 ```
@@ -71,7 +71,7 @@ f(x)
 
 In [4]:
 
-```
+```py
 def mod_f(x):
     x[0] = 999
     return x
@@ -84,7 +84,7 @@ print x
 
 ```
 
-```
+```py
 [1, 2, 3]
 [999, 2, 3]
 [999, 2, 3]
@@ -93,7 +93,7 @@ print x
 
 In [5]:
 
-```
+```py
 def no_mod_f(x):
     x = [4, 5, 6]
     return x
@@ -106,7 +106,7 @@ print x
 
 ```
 
-```
+```py
 [1, 2, 3]
 [4, 5, 6]
 [1, 2, 3]
@@ -121,7 +121,7 @@ print x
 
 In [6]:
 
-```
+```py
 def f(x = []):
     x.append(1)
     return x
@@ -132,7 +132,7 @@ def f(x = []):
 
 In [7]:
 
-```
+```py
 print f()
 print f()
 print f()
@@ -142,7 +142,7 @@ print f()
 
 ```
 
-```
+```py
 [1]
 [1, 1]
 [1, 1, 1]
@@ -156,7 +156,7 @@ print f()
 
 In [8]:
 
-```
+```py
 def f(x = None):
     if x is None:
         x = []
@@ -172,7 +172,7 @@ print f()
 
 ```
 
-```
+```py
 [1]
 [1]
 [1]
@@ -188,34 +188,34 @@ print f()
 
 `map(f, sq)` 函数将 `f` 作用到 `sq` 的每个元素上去，并返回结果组成的列表，相当于：
 
-```
+```py
 [f(s) for s in sq]
 
 ```
 
 In [9]:
 
-```
+```py
 map(square, range(5))
 
 ```
 
 Out[9]:
 
-```
+```py
 [0, 1, 4, 9, 16]
 ```
 
 `filter(f, sq)` 函数的作用相当于，对于 `sq` 的每个元素 `s`，返回所有 `f(s)` 为 `True` 的 `s` 组成的列表，相当于：
 
-```
+```py
 [s for s in sq if f(s)]
 
 ```
 
 In [10]:
 
-```
+```py
 def is_even(x):
     return x % 2 == 0
 
@@ -225,7 +225,7 @@ filter(is_even, range(5))
 
 Out[10]:
 
-```
+```py
 [0, 2, 4]
 ```
 
@@ -233,14 +233,14 @@ Out[10]:
 
 In [11]:
 
-```
+```py
 map(square, filter(is_even, range(5)))
 
 ```
 
 Out[11]:
 
-```
+```py
 [0, 4, 16]
 ```
 
@@ -248,7 +248,7 @@ Out[11]:
 
 In [12]:
 
-```
+```py
 def my_add(x, y):
     return x + y
 
@@ -258,7 +258,7 @@ reduce(my_add, [1,2,3,4,5])
 
 Out[12]:
 
-```
+```py
 15
 ```
 
@@ -268,7 +268,7 @@ Out[12]:
 
 In [13]:
 
-```
+```py
 def make_logger(target):
     def logger(data):
         with open(target, 'a') as f:
@@ -283,12 +283,12 @@ foo_logger('World')
 
 In [14]:
 
-```
+```py
 !cat foo.txt
 
 ```
 
-```
+```py
 Hello
 World
 
@@ -296,7 +296,7 @@ World
 
 In [15]:
 
-```
+```py
 import os
 os.remove('foo.txt')
 
@@ -306,7 +306,7 @@ os.remove('foo.txt')
 
 在使用 `map`， `filter`，`reduce` 等函数的时候，为了方便，对一些简单的函数，我们通常使用匿名函数的方式进行处理，其基本形式是：
 
-```
+```py
 lambda <variables>: <expression> 
 ```
 
@@ -314,12 +314,12 @@ lambda <variables>: <expression>
 
 In [16]:
 
-```
+```py
 print map(square, range(5))
 
 ```
 
-```
+```py
 [0, 1, 4, 9, 16]
 
 ```
@@ -328,12 +328,12 @@ print map(square, range(5))
 
 In [17]:
 
-```
+```py
 print map(lambda x: x * x, range(5))
 
 ```
 
-```
+```py
 [0, 1, 4, 9, 16]
 
 ```
@@ -342,13 +342,13 @@ print map(lambda x: x * x, range(5))
 
 In [18]:
 
-```
+```py
 s1 = reduce(lambda x, y: x+y, map(lambda x: x**2, range(1,10)))
 print(s1)
 
 ```
 
-```
+```py
 285
 
 ```
@@ -357,13 +357,13 @@ print(s1)
 
 In [19]:
 
-```
+```py
 s2 = sum(x**2 for x in range(1, 10))
 print s2
 
 ```
 
-```
+```py
 285
 
 ```
@@ -374,7 +374,7 @@ print s2
 
 In [20]:
 
-```
+```py
 x = 15
 
 def print_x():
@@ -384,7 +384,7 @@ print_x()
 
 ```
 
-```
+```py
 15
 
 ```
@@ -393,7 +393,7 @@ print_x()
 
 In [21]:
 
-```
+```py
 x = 15
 
 def print_newx():
@@ -407,7 +407,7 @@ print x
 
 ```
 
-```
+```py
 18
 18
 
@@ -417,7 +417,7 @@ print x
 
 In [22]:
 
-```
+```py
 x = 15
 
 def print_newx():
@@ -430,7 +430,7 @@ print x
 
 ```
 
-```
+```py
 18
 15
 
@@ -444,7 +444,7 @@ Fibocacci 数列：
 
 In [23]:
 
-```
+```py
 def fib1(n):
     """Fib with recursion."""
 
@@ -459,7 +459,7 @@ print [fib1(i) for i in range(10)]
 
 ```
 
-```
+```py
 [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
 
 ```
@@ -468,7 +468,7 @@ print [fib1(i) for i in range(10)]
 
 In [24]:
 
-```
+```py
 def fib2(n):
     """Fib without recursion."""
     a, b = 0, 1
@@ -480,7 +480,7 @@ print [fib2(i) for i in range(10)]
 
 ```
 
-```
+```py
 [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
 
 ```
@@ -489,13 +489,13 @@ print [fib2(i) for i in range(10)]
 
 In [25]:
 
-```
+```py
 %timeit fib1(20)
 %timeit fib2(20)
 
 ```
 
-```
+```py
 100 loops, best of 3: 5.35 ms per loop
 100000 loops, best of 3: 2.2 µs per loop
 
@@ -507,7 +507,7 @@ In [25]:
 
 In [26]:
 
-```
+```py
 def fib3(n, cache={0: 1, 1: 1}):
     """Fib with recursion and caching."""
 
@@ -525,7 +525,7 @@ print [fib3(i) for i in range(10)]
 
 ```
 
-```
+```py
 [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
 100 loops, best of 3: 5.37 ms per loop
 100000 loops, best of 3: 2.19 µs per loop