字符编码
编程规范（PEP8）
变量1.常量（用大写）
2.变量
常用类型：str 、int、float、 long、bool
字串格式化：
%d 整数
%2d占两位 %02d占两位用0填充%f 浮点数%.2f取两位小数%s字符串%x十六进制整数%%表示 %#单行注解'''多行注解
>>>n = "abc"
>>>print('i can say %s' %n)
结果：i can say abc
字符串常用功能：
清除空格 strip
分割 split
获得长度 len(obj)
索引 obj[1]
切片 obj[1:10]
列表创建
>>> n = ["abc"]>>> n['abc']
>>> n = list('abc')>>> n['a', 'b', 'c']
列表常见方法
Eng是一个list
>>>Eng = ['a','b','c']>>>Eng
>>>['a','b','c']
用索引来访问list
>>>Eng[0]
>>>['a']
用len来获得list元素个数
>>> len(Eng)
结果：3
追加一个元素
Eng.append('d')
删除最后一个元素
Eng.pop()
删除类表种的指定位置的一个元素
Eng.pop(1)
删除一个指定元素
Eng.remove('b')
获得列表的最后一个元素[-1]依此类推[-2]..可以获得倒是第2...个元素
>>> all_item = 95>>> pager =10>>> result = all_item.__divmod__(pager)>>> result(9, 5)
>>> age = 18>>> result = age.__eq__(19)>>> resultFalse
>>> age = 18>>> result = age.__float__()>>> result18.0
>>> age.__floordiv__(9)2>>> age.__floordiv__(19)0>>> 18//190
>>> dir(name)['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
>>> print(type(name))<class 'str'>
>>> name = 'eric'>>> name.capitalize()'Eric'
>>> name="Alen">>> result = name.center(20)>>> print(result) Alen
>>> result = name.center(20,'_')>>> print(result)________Alen________
>>> s = 'abcdabcddcfbgklmlllc'>>> s.count('d')3>>> s.count('d',1,5)1
>>> name = 'Alan'>>> result = name.endswith('d')>>> resultFalse>>> result = name.endswith('n')>>> resultTrue
>>> result = name.endswith('a',0,3)>>> resultTrue
>>> name = 'a\tl\tan'>>> result = name.expandtabs()>>> result'a l an'
>>> name = 'abcdefgabcdefggg'>>> result = name.find('e')>>> result4>>> result2 = name.index('e')>>> result24>>> result2 = name.index('p')Traceback (most recent call last): File "<stdin>", line 1, in <module>ValueError: substring not found
>>> w = 'i would like {0} {1}'>>> result = w.format('a','coffe')>>> result'i would like a coffe'>>>
>>> w = 'i would like {id} {name}'>>> result = w.format(id='a',name='Alan')>>> result'i would like a Alan'
>>> name = list('Alan')>>> name['A', 'l', 'a', 'n']>>> result ="".join(name)>>> result'Alan'
>>> w = 'youareright'>>> result = w.partition("are")>>> result('you', 'are', 'right')
>>> w = 'you are right'>>> result = w.replace('right','wrong')>>> result'you are wrong'
>>> a = 'one two three four'>>> result.replace('o', 'i',1)'y-u are right'>>> result=a.replace('o', 'i',1)>>> result'ine two three four'>>> result=a.replace('o', 'i',2)>>> result'ine twi three four'
>>> l1 = ['a','b','c']>>> l1.extend(['d','e',])>>> l1['a', 'b', 'c', 'd', 'e']
>>> l1.append('A')>>> li>>> l1['a', 'b', 'c', 'd', 'e', 'A']
['a', 'b', 'c', 'd', 'e', 'A']>>> l1.insert(0,'B')>>> l1['B', 'a', 'b', 'c', 'd', 'e', 'A']
>>> l1['B', 'a', 'b', 'c', 'd', 'e', 'A']>>> ret = l1.pop(0)>>> print(l1)['a', 'b', 'c', 'd', 'e', 'A']>>> print(ret)B
>>> l1.remove('A')>>> l1['a', 'b', 'c', 'd', 'e']
>>> l1.reverse()>>> l1['e', 'd', 'c', 'b', 'a']
>> dic = dict(k1='v1',k2='v2')>>> dic{'k1': 'v1', 'k2': 'v2'}>>> new_dic = dic.fromkeys(['k1'],'v1')>>> new_dic{'k1': 'v1'}
dic =['k1':'v1','k2':'v2']
dic =['k1']
>> dic = {'k1':'v1','k2':'v2'}>>> dic['k1']'v1'>>> dic['k3']Traceback (most recent call last): File "<stdin>", line 1, in <module>KeyError: 'k3'>>> dic.get('k3')>>> print(dic.get('k3'))None>>> print(dic.get('k3','没有数据！'))没有数据！
>>> print(dic.keys())dict_keys(['k1', 'k2'])>>> print(dic.values())dict_values(['v1', 'v2'])>>> print(dic.items())dict_items([('k1', 'v1'), ('k2', 'v2')])
>> dic{'k4': 'v4', 'k1': 123, 'k2': 'v2', 'k3': 'v3'}>>> ret = dic.update({'k1':234})>>> print(ret)None>>> ret>>> dic{'k4': 'v4', 'k1': 234, 'k2': 'v2', 'k3': 'v3'}
dic_list = [11,22,33,44,55,66,77,88,99,90]dic = {}for i in dic_list: if i>66: if "k1" in dic.keys(): dic['k1'].append(i) else: dic['k1'] =[i] if i<=66: if "k2" in dic.keys(): dic['k2'].append(i) else: dic['k2']=[i]print(dic)
Eng[-1]
在列表的指定位置插入一个元素
Eng(1,'b')
Tuple元组基本操作
特性：1）元组的元素为只读（不修改）
>>> tl = ('a','b','c','c')>>> tl[0]='1'Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: 'tuple' object does not support item assignment
2）元组的元素的元素可修改
>>> tl = ('a','b',{'k1':'v1'},'c')>>> tl[2]['k1']'v1'>>> tl[2]['k1'] = 'p1'>>> tl('a', 'b', {'k1': 'p1'}, 'c')
转载于:https://www.cnblogs.com/luoye00/p/5152803.html
