~~~
i = 0
while i < len(my_list):
v = my_list[1]
print(v)
i += 1
~~~
~~~
for i in range(len(my_list)):
v = my_list[i]
print(v)
~~~
~~~
for v in my_list:
print(v)
~~~
#the for loop
~~~
for name in iterable:
statements
~~~
#list -> elements
~~~
for e in [1,2,3,4]:
print(e)
~~~
#strings ->characters
~~~
for c in 'hello':
print(c)
~~~
#dicts -> keys
~~~
for k in {'a':1,'b':2}:
print (k)
~~~
also
~~~
for v in d.itervalues():
pass
for k,v in d.iteritems():
pass
~~~
#file -> lines
~~~
with open('filename') as f:
for line in f:
print repr(line)
~~~
#stdlib has interesting iterables
~~~
for match in re.finditer(pattern, string):
pass
for root, dirs, files in os.walk('/some/dir'):
pass
~~~
~~~
for num in itertools.count():
pass
~~~
#other users for iterables
`new_list = list(iterable)`
~~~
results = [ f(x) for x in iterable ]
total = sum(iterable)
smallest = min(iterable)
largest = max(iterable)
~~~
#get index enumerate() makes useful pairs
~~~
names = ['a','b','c']
list(enumerate(names))
~~~
```
[(0,'a'),
(1,'b'),
(2,'c')
]
```
~~~
for num, name in enumerate(names):
print(num, name)
~~~
- python核心
- python27编译安装
- 原处修改以及拷贝
- loop
- 内置的变量
- 内置类型
- python内置方法
- 内置方法列表
- 求绝对值-abs
- 求商取余-divmod
- 交换输入-input
- [未完]文件打开函数-open
- staticmethod
- 判断迭代对象真假all
- 判断迭代对象真假any
- 枚举对象enumerate
- 整数转换类型int
- ascii码转换ord-chr-unichr
- 类型转换str
- python执行字符串表达式eval
- 类型判断isinstance
- 数学计算pow
- 数学计算和sum
- 不可变集合frozenset
- zip
- 比较cmp
- basestring类型判断
- 反转序列迭代器resversed
- python模块
- glob
- sys.argvgetopt-argparse
- os
- sys
- requests
- random
- time
- date
- zlib-gzip-bz2-zipfile-tarfile
- ftp
- paramiko
- pexpect
- 数据库模块
- redis
- mysql
- mongodb
- __builtin__
- 学生PYTHON分享
- 学生运维分享