From ba5c351f216ca63e4f46230db683224fd6d26355 Mon Sep 17 00:00:00 2001 From: Geoff Liu Date: Fri, 31 Oct 2014 15:40:49 -0600 Subject: A bit of section 2, 3, 4 --- zh-cn/python3-cn.html.markdown | 90 +++++++++++++++++++++--------------------- 1 file changed, 45 insertions(+), 45 deletions(-) (limited to 'zh-cn') diff --git a/zh-cn/python3-cn.html.markdown b/zh-cn/python3-cn.html.markdown index e297a7ce..78ecb4af 100644 --- a/zh-cn/python3-cn.html.markdown +++ b/zh-cn/python3-cn.html.markdown @@ -140,60 +140,60 @@ bool({}) #=> False ## 2. 变量和集合 #################################################### -# Python has a print function +# print是内置的打印函数 print("I'm Python. Nice to meet you!") -# No need to declare variables before assigning to them. -# Convention is to use lower_case_with_underscores +# 在给变量赋值前不用提前声明 +# 传统的变量命名是小写,用下划线分隔单词 some_var = 5 some_var # => 5 -# Accessing a previously unassigned variable is an exception. -# See Control Flow to learn more about exception handling. -some_unknown_var # Raises a NameError +# 存取未赋值的变量会抛出异常 +# 下面流程控制一段更深入讲解异常处理 +some_unknown_var # 抛出NameError -# Lists store sequences +# 用列表(list)储存序列 li = [] -# You can start with a prefilled list +# 创建列表时也可以同时赋给元素 other_li = [4, 5, 6] -# Add stuff to the end of a list with append -li.append(1) # li is now [1] -li.append(2) # li is now [1, 2] -li.append(4) # li is now [1, 2, 4] -li.append(3) # li is now [1, 2, 4, 3] -# Remove from the end with pop -li.pop() # => 3 and li is now [1, 2, 4] -# Let's put it back -li.append(3) # li is now [1, 2, 4, 3] again. - -# Access a list like you would any array +# 用append在列表最后追加元素 +li.append(1) # li现在是[1] +li.append(2) # li现在是[1, 2] +li.append(4) # li现在是[1, 2, 4] +li.append(3) # li现在是[1, 2, 4, 3] +# 用pop从列表尾部删除 +li.pop() # => 3 且li现在是[1, 2, 4] +# 把3再放回去 +li.append(3) # li变回[1, 2, 4, 3] + +# 列表取值跟数组一样 li[0] # => 1 -# Look at the last element +# 取出最后一个元素 li[-1] # => 3 -# Looking out of bounds is an IndexError -li[4] # Raises an IndexError +# 越界读取会造成IndexError +li[4] # 抛出IndexError -# You can look at ranges with slice syntax. +# 列表的切割语法 # (It's a closed/open range for you mathy types.) li[1:3] # => [2, 4] -# Omit the beginning +# 取尾 li[2:] # => [4, 3] -# Omit the end +# 取头 li[:3] # => [1, 2, 4] -# Select every second entry +# 每两个取一个 li[::2] # =>[1, 4] -# Revert the list +# 倒排列表 li[::-1] # => [3, 4, 2, 1] # Use any combination of these to make advanced slices # li[start:end:step] -# Remove arbitrary elements from a list with "del" +# 用del删除任何一个元素 del li[2] # li is now [1, 2, 3] -# You can add lists -# Note: values for li and for other_li are not modified. +# 列表可以相加 +# 注意:li和other_li的值都不变 li + other_li # => [1, 2, 3, 4, 5, 6] # Concatenate lists with "extend()" @@ -211,7 +211,7 @@ tup = (1, 2, 3) tup[0] # => 1 tup[0] = 3 # Raises a TypeError -# You can do all those list thingies on tuples too +# 列表允许的操作元组也可以 len(tup) # => 3 tup + (4, 5, 6) # => (1, 2, 3, 4, 5, 6) tup[:2] # => (1, 2) @@ -301,17 +301,17 @@ filled_set | other_set # => {1, 2, 3, 4, 5, 6} ## 3. 流程控制和迭代器 #################################################### -# Let's just make a variable +# 先随便定义一个变量 some_var = 5 -# Here is an if statement. Indentation is significant in python! -# prints "some_var is smaller than 10" +# 这是个if语句。注意缩进在Python里是有意义的 +# 印出"some_var比10小" if some_var > 10: - print("some_var is totally bigger than 10.") -elif some_var < 10: # This elif clause is optional. - print("some_var is smaller than 10.") -else: # This is optional too. - print("some_var is indeed 10.") + print("some_var比10大") +elif some_var < 10: # elif句是可选的 + print("some_var比10小") +else: # else也是可选的 + print("some_var就是10") """ @@ -399,16 +399,16 @@ list(filled_dict.keys()) #=> Returns ["one", "two", "three"] ## 4. 函数 #################################################### -# Use "def" to create new functions +# 用def定义新函数 def add(x, y): print("x is {} and y is {}".format(x, y)) - return x + y # Return values with a return statement + return x + y # 用return语句返回 -# Calling functions with parameters -add(5, 6) # => prints out "x is 5 and y is 6" and returns 11 +# 调用函数 +add(5, 6) # => 印出"x is 5 and y is 6"并且返回11 -# Another way to call functions is with keyword arguments -add(y=6, x=5) # Keyword arguments can arrive in any order. +# 也可以用关键字参数来调用函数 +add(y=6, x=5) # 关键字参数可以用任何顺序 # You can define functions that take a variable number of -- cgit v1.2.3