Python学习【第七篇】基本数据类型
基本数据类型
bytes数据类型
Python 3最重要的新特性大概要算是对文本和二进制数据作了更为清晰的区分。文本总是Unicode，由str类型表示，二进制数据则由bytes类型表示。Python 3不会以任意隐式的方式混用str和bytes，正是这使得两者的区分特别清晰。你不能拼接字符串和字节包，也无法在字节包里搜索字符串（反之亦然），也不能将字符串传入参数为字节包的函数（反之亦然）。这是件好事。
不管怎样，字符串和字节包之间的界线是必然的，下面的图解非常重要，务请牢记于心：
字符串可以编码成字节包，而字节包可以解码成字符串。
>>>'€20'.encode('utf-8')
b'\xe2\x82\xac20'
>>> b'\xe2\x82\xac20'.decode('utf-8')
'€20'
数字
2是一个整数的例子。
长整数 不过是大一些的整数。
3.23和52.3E-4是浮点数的例子，E标记表示10的幂。在这里，52.3E-4表示52.3*10-4.
(-5+4j)和(2.3-4.6j)是复数的例子，其中-5，4为实数，j为虚数，数学中表示复数是什么？。
int（整型）
在32位机器上，整数的位数为32位，取值范围为-2**31～2**31-1，即-2147483648～2147483647
在64位系统上，整数的位数为64位，取值范围为-2**63～2**63-1，即-9223372036854775808～9223372036854775807
在64位系统上，整数的位数为64位，取值范围为-2**63～2**63-1，即-9223372036854775808～9223372036854775807
class int(object): """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) """ def bit_length(self): """ 返回表示该数字的时占用的最少位数 """ """ int.bit_length() -> int Number of bits necessary to represent self in binary. >>> bin(37) '0b100101' >>> (37).bit_length() """ return 0 def conjugate(self, *args, **kwargs): # real signature unknown """ 返回该复数的共轭复数 """ """ Returns self, the complex conjugate of any int. """ pass def __abs__(self): """ 返回绝对值 """ """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __and__(self, y): """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): """ 比较两个数大小 """ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __coerce__(self, y): """ 强制生成一个元组 """ """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): """ 相除，得到商和余数组成的元组 """ """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): """ x.__div__(y) <==> x/y """ pass def __float__(self): """ 转换为浮点类型 """ """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, *args, **kwargs): # real signature unknown pass def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown """ 内部调用 __new__方法或创建对象时传入参数使用 """ pass def __hash__(self): """如果对象object为哈希表类型，返回对象object的哈希值。哈希值为整数。在字典查找中，哈希值用于快速比较字典的键。两个数值如果相等，则哈希值也相等。""" """ x.__hash__() <==> hash(x) """ pass def __hex__(self): """ 返回当前数的 十六进制 表示 """ """ x.__hex__() <==> hex(x) """ pass def __index__(self): """ 用于切片，数字无意义 """ """ x[y:z] <==> x[y.__index__():z.__index__()] """ pass def __init__(self, x, base=10): # known special case of int.__init__ """ 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """ """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) # (copied from class doc) """ pass def __int__(self): """ 转换为整数 """ """ x.__int__() <==> int(x) """ pass def __invert__(self): """ x.__invert__() <==> ~x """ pass def __long__(self): """ 转换为长整数 """ """ x.__long__() <==> long(x) """ pass def __lshift__(self, y): """ x.__lshift__(y) <==> x<<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): """ x.__mul__(y) <==> x*y """ pass def __neg__(self): """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __nonzero__(self): """ x.__nonzero__() <==> x != 0 """ pass def __oct__(self): """ 返回改值的 八进制 表示 """ """ x.__oct__() <==> oct(x) """ pass def __or__(self, y): """ x.__or__(y) <==> x|y """ pass def __pos__(self): """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): """ 幂，次方 """ """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): """ x.__radd__(y) <==> y+x """ pass def __rand__(self, y): """ x.__rand__(y) <==> y&x """ pass def __rdivmod__(self, y): """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): """转化为解释器可读取的形式 """ """ x.__repr__() <==> repr(x) """ pass def __str__(self): """转换为人阅读的形式，如果没有适于人阅读的解释形式的话，则返回解释器课阅读的形式""" """ x.__str__() <==> str(x) """ pass def __rfloordiv__(self, y): """ x.__rfloordiv__(y) <==> y//x """ pass def __rlshift__(self, y): """ x.__rlshift__(y) <==> y<<x """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): """ x.__rmul__(y) <==> y*x """ pass def __ror__(self, y): """ x.__ror__(y) <==> y|x """ pass def __rpow__(self, x, z=None): """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rrshift__(self, y): """ x.__rrshift__(y) <==> y>>x """ pass def __rshift__(self, y): """ x.__rshift__(y) <==> x>>y """ pass def __rsub__(self, y): """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): """ x.__rtruediv__(y) <==> y/x """ pass def __rxor__(self, y): """ x.__rxor__(y) <==> y^x """ pass def __sub__(self, y): """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): """ 返回数值被截取为整形的值，在整形中无意义 """ pass def __xor__(self, y): """ x.__xor__(y) <==> x^y """ pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 分母 = 1 """ """the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 虚数，无意义 """ """the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 分子 = 数字大小 """ """the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 实属，无意义 """ """the real part of a complex number""" int
long(长整型)
跟C语言不同，Python的长整数没有指定位宽，即：Python没有限制长整数数值的大小，但实际上由于机器内存有限，我们使用的长整数数值不可能无限大。
注意，自从Python2.2起，如果整数发生溢出，Python会自动将整数数据转换为长整数，所以如今在长整数数据后面不加字母L也不会导致严重后果了。
float （浮点型）
浮点数用来处理实数，即带有小数的数字。类似于C语言中的double类型，占8个字节（64位），其中52位表示底，11位表示指数，剩下的一位表示符号。
complex（复数）
复数由实数部分和虚数部分组成，一般形式为x + yj，其中的x是复数的实数部分，y是复数的虚数部分，这里的x和y都是实数。
注：Python中存在小数池-5～257
布尔值
布尔值在Python中如何定义呢？
>>>True True >>>False False #注意！都是大写
真或假
1或0
>>>0 == True False >>>0 == False True #由此可见0代表False，而1代表True
字符串
"Hello world"
万恶的字符串拼接：
python中的字符串在C语言中体现为是一个字符数组，每次创建字符串时候需要在内存中开辟一块连续的空，并且一旦需要修改字符串的话，就需要再次开辟空间，万恶的+号每出现一次就会在内存中重新开辟一块空间像下面这样，所以我们要尽量避免这样的情况发生：
>>>name = 'bourbon'
#开辟了3快内存空间，需要去内存里找3次，把数据拼出来
>>>print("my name is " + name + "and you ?")
#输出
my name is bourbon and you ?
字符串格式化
>>>name='bourbon' >>>print "i am %s" %name #输出 i am bourbon
PS:字符串是%s;整数%d;浮点数%f
1 name = input("input your name:") 2 age = int(input("input your age:")) 3 job = input("input your job:") 4 5 msg = ''' 6 information of user %s: 7 ---------------------- 8 name: %s 9 age : %d 10 job : %s 11 --------End----------- 12 ''' % (name,name,age,job ) 13 print(msg)
字符串功能：
· 移除空白
username = input("input your name:")
if username.strip() == "bourbon":
print("welcome")
#strip() 移除首尾的空白
· 分割
>>>name = "bourbon,jacky,lio"
>>>name2 = name.split(",")
>>>print(name2)
#按照","进行拆分，将字符串拆成一个列表
['bourbon', 'jacky', 'lio']
>>>name = "bourbon,jacky,lio"
>>>name2 = name.split(",")
>>>print("|".join(name2))
#按照"|"将列表里的每一个元素重新合成一个新的字符串
bourbon|jacky|lio
· 长度
· 索引
· 切片
name = "Bourbon Tian" print(name[2:4]) # 输出 ur
name = "sheldon"
# 以什么结尾
print(name.endswith("on"))
# 以什么开头
print(name.startswith("on"))
# 全大写
print(name.upper())
# 全小写
print(name.lower())
# 输出
True
False
SHELDON
sheldon
>>>name = "bourbon tian" >>>print(name.center(40,'-')) --------------bourbon tian--------------
class str(basestring): """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. """ def capitalize(self): """ 首字母变大写 """ """ S.capitalize() -> string Return a copy of the string S with only its first character capitalized. """ return "" def center(self, width, fillchar=None): """ 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """ """ S.center(width[, fillchar]) -> string Return S centered in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def count(self, sub, start=None, end=None): """ 子序列个数 """ """ S.count(sub[, start[, end]]) -> int Return the number of non-overlapping occurrences of substring sub in string S[start:end]. Optional arguments start and end are interpreted as in slice notation. """ return 0 def decode(self, encoding=None, errors=None): """ 解码 """ """ S.decode([encoding[,errors]]) -> object Decodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeDecodeError. Other possible values are 'ignore' and 'replace' as well as any other name registered with codecs.register_error that is able to handle UnicodeDecodeErrors. """ return object() def encode(self, encoding=None, errors=None): """ 编码，针对unicode """ """ S.encode([encoding[,errors]]) -> object Encodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and 'xmlcharrefreplace' as well as any other name registered with codecs.register_error that is able to handle UnicodeEncodeErrors. """ return object() def endswith(self, suffix, start=None, end=None): """ 是否以 xxx 结束 """ """ S.endswith(suffix[, start[, end]]) -> bool Return True if S ends with the specified suffix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. suffix can also be a tuple of strings to try. """ return False def expandtabs(self, tabsize=None): """ 将tab转换成空格，默认一个tab转换成8个空格 """ """ S.expandtabs([tabsize]) -> string Return a copy of S where all tab characters are expanded using spaces. If tabsize is not given, a tab size of 8 characters is assumed. """ return "" def find(self, sub, start=None, end=None): """ 寻找子序列位置，如果没找到，返回 -1 """ """ S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def format(*args, **kwargs): # known special case of str.format """ 字符串格式化，动态参数，将函数式编程时细说 """ """ S.format(*args, **kwargs) -> string Return a formatted version of S, using substitutions from args and kwargs. The substitutions are identified by braces ('{' and '}'). """ pass def index(self, sub, start=None, end=None): """ 子序列位置，如果没找到，报错 """ S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found. """ return 0 def isalnum(self): """ 是否是字母和数字 """ """ S.isalnum() -> bool Return True if all characters in S are alphanumeric and there is at least one character in S, False otherwise. """ return False def isalpha(self): """ 是否是字母 """ """ S.isalpha() -> bool Return True if all characters in S are alphabetic and there is at least one character in S, False otherwise. """ return False def isdigit(self): """ 是否是数字 """ """ S.isdigit() -> bool Return True if all characters in S are digits and there is at least one character in S, False otherwise. """ return False def islower(self): """ 是否小写 """ """ S.islower() -> bool Return True if all cased characters in S are lowercase and there is at least one cased character in S, False otherwise. """ return False def isspace(self): """ S.isspace() -> bool Return True if all characters in S are whitespace and there is at least one character in S, False otherwise. """ return False def istitle(self): """ S.istitle() -> bool Return True if S is a titlecased string and there is at least one character in S, i.e. uppercase characters may only follow uncased characters and lowercase characters only cased ones. Return False otherwise. """ return False def isupper(self): """ S.isupper() -> bool Return True if all cased characters in S are uppercase and there is at least one cased character in S, False otherwise. """ return False def join(self, iterable): """ 连接 """ """ S.join(iterable) -> string Return a string which is the concatenation of the strings in the iterable. The separator between elements is S. """ return "" def ljust(self, width, fillchar=None): """ 内容左对齐，右侧填充 """ """ S.ljust(width[, fillchar]) -> string Return S left-justified in a string of length width. Padding is done using the specified fill character (default is a space). """ return "" def lower(self): """ 变小写 """ """ S.lower() -> string Return a copy of the string S converted to lowercase. """ return "" def lstrip(self, chars=None): """ 移除左侧空白 """ """ S.lstrip([chars]) -> string or unicode Return a copy of the string S with leading whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def partition(self, sep): """ 分割，前，中，后三部分 """ """ S.partition(sep) -> (head, sep, tail) Search for the separator sep in S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return S and two empty strings. """ pass def replace(self, old, new, count=None): """ 替换 """ """ S.replace(old, new[, count]) -> string Return a copy of string S with all occurrences of substring old replaced by new. If the optional argument count is given, only the first count occurrences are replaced. """ return "" def rfind(self, sub, start=None, end=None): """ S.rfind(sub [,start [,end]]) -> int Return the highest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def rindex(self, sub, start=None, end=None): """ S.rindex(sub [,start [,end]]) -> int Like S.rfind() but raise ValueError when the substring is not found. """ return 0 def rjust(self, width, fillchar=None): """ S.rjust(width[, fillchar]) -> string Return S right-justified in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def rpartition(self, sep): """ S.rpartition(sep) -> (head, sep, tail) Search for the separator sep in S, starting at the end of S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return two empty strings and S. """ pass def rsplit(self, sep=None, maxsplit=None): """ S.rsplit([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string, starting at the end of the string and working to the front. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator. """ return [] def rstrip(self, chars=None): """ S.rstrip([chars]) -> string or unicode Return a copy of the string S with trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def split(self, sep=None, maxsplit=None): """ 分割， maxsplit最多分割几次 """ """ S.split([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator and empty strings are removed from the result. """ return [] def splitlines(self, keepends=False): """ 根据换行分割 """ """ S.splitlines(keepends=False) -> list of strings Return a list of the lines in S, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true. """ return [] def startswith(self, prefix, start=None, end=None): """ 是否起始 """ """ S.startswith(prefix[, start[, end]]) -> bool Return True if S starts with the specified prefix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. prefix can also be a tuple of strings to try. """ return False def strip(self, chars=None): """ 移除两段空白 """ """ S.strip([chars]) -> string or unicode Return a copy of the string S with leading and trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def swapcase(self): """ 大写变小写，小写变大写 """ """ S.swapcase() -> string Return a copy of the string S with uppercase characters converted to lowercase and vice versa. """ return "" def title(self): """ S.title() -> string Return a titlecased version of S, i.e. words start with uppercase characters, all remaining cased characters have lowercase. """ return "" def translate(self, table, deletechars=None): """ 转换，需要先做一个对应表，最后一个表示删除字符集合 intab = "aeiou" outtab = "12345" trantab = maketrans(intab, outtab) str = "this is string example....wow!!!" print str.translate(trantab, 'xm') """ """ S.translate(table [,deletechars]) -> string Return a copy of the string S, where all characters occurring in the optional argument deletechars are removed, and the remaining characters have been mapped through the given translation table, which must be a string of length 256 or None. If the table argument is None, no translation is applied and the operation simply removes the characters in deletechars. """ return "" def upper(self): """ S.upper() -> string Return a copy of the string S converted to uppercase. """ return "" def zfill(self, width): """方法返回指定长度的字符串，原字符串右对齐，前面填充0。""" """ S.zfill(width) -> string Pad a numeric string S with zeros on the left, to fill a field of the specified width. The string S is never truncated. """ return "" def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown pass def _formatter_parser(self, *args, **kwargs): # real signature unknown pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): """ x.__eq__(y) <==> x==y """ pass def __format__(self, format_spec): """ S.__format__(format_spec) -> string Return a formatted version of S as described by format_spec. """ return "" def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): """ x.__gt__(y) <==> x>y """ pass def __hash__(self): """ x.__hash__() <==> hash(x) """ pass def __init__(self, string=''): # known special case of str.__init__ """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. # (copied from class doc) """ pass def __len__(self): """ x.__len__() <==> len(x) """ pass def __le__(self, y): """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): """ x.__lt__(y) <==> x<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, n): """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): """ x.__repr__() <==> repr(x) """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, n): """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __str__(self): """ x.__str__() <==> str(x) """ pass
列表
创建列表：
>>>age = 9 >>>name = ["jack","jerry","jason",22,age] >>>print（name） ['jack','jerry','jason',22,9]
列表都是"[]"号开始，通过","隔开，字符串是元素，元素也可以是数字、变量。
基本操作：
· 索引
第一个索引是0，第二个索引是1，以此类推。
>>>name[0] 'jack' >>>name[1] 'jerry' >>>name[-1] 9 >>>name[-2] 22
· 切片
>>>name[0:2] #虎头蛇尾，永远不包含最后一个 ['jack','jerry'] >>>name[0:2][0] 'jack' >>>name[0:2][0][1] 'a'
PS:只能正着取值
· 更改插入追加
#更改
>>>name[1] = "bourbon"
>>>name
['jack','bourbon','jason',22,9]
#插入
>>>name.insert(2,'lio')
>>>name
['jack','bourbon','lio','jason',22,9]
#追加
>>>name.append("eric")
>>>name
['jack','bourbon','lio','jason',22,9,'eric']
· 删除
>>>name.remove("lio")
>>>name
['jack','bourbon','jason',22,9,'eric']
>>>del name[1]
>>>name
['jack','jason',22,9,'eric']
#name.pop(“这里输入下标”) ，默认删除最后一个下标。
>>>name.pop()
'eric'
>>>name
['jack','jason',22,9]
· 长度
· 循环
· 包含
扩展表 >>>name = [32,23,21,52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name2 = [453,5435,76575,2132] >>>name.extend(name2) >>>print(name) [32, 23, 21, 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9, 453, 5435, 76575, 2132] 反转表 >>>name = [32,23,21,52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name.reverse() >>>print(name) [9, 9, 4335, 2134, 5435, 98, 76, 68, 7, 546, 14, 52, 21, 23, 32] 排序表 >>>name = [32,23,21,52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name.sort() >>>print (name) [7, 9, 9, 14, 21, 23, 32, 52, 68, 76, 98, 546, 2134, 4335, 5435] 清空表 >>>name.clear() >>>print(name) [] 拷贝表 >>>name = [32,23,21,52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name3 = name.copy() >>>name[0] = "Alex" >>>print(name3) >>>print(name) [32, 23, 21, 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] #PS:python 默认只copy第一层,因为copy的内存地址 >>>name = [32,23,21,[1321,124314,45654,342],52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name3 = name.copy() >>>name[0] = "Bourbon" >>>name[3][0] = 11111 >>>print(name3) >>>print(name) [32, 23, 21, [11111, 124314, 45654, 342], 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] ['Bourbon', 23, 21, [11111, 124314, 45654, 342], 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] >>>print(id(name[3]),id(name3[3])) 8632520 8632520 PS：深度copy的方式 >>>import copy >>>name = [32,23,21,[1321,124314,45654,342],52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>name3 = name.copy() >>>name4 = copy.deepcopy(name) #深度copy >>>name[0] = "Bourbon" >>>name[3][0] = 11111 >>>print(name3) >>>print(name) >>>print(name4) [32, 23, 21, [11111, 124314, 45654, 342], 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] ['Bourbon', 23, 21, [11111, 124314, 45654, 342], 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] [32, 23, 21, [1321, 124314, 45654, 342], 52, 14, 546, 7, 68, 76, 98, 5435, 2134, 4335, 9, 9] >>>print(id(name[3]),id(name4[3])) 7781128 7780232 显示列表的长度 >>>name = [32,23,21,[1321,124314,45654,342],52,14,546,7,68,76,98,5435,2134,4335,9,9] >>>print(len(name)) 16
· 查询
a = ['jerry','jacky','jason','bourbon']
print(a.index("jason"))
# 输出
2
· 枚举
#枚举函数，打印下表：
a = ['jarry','jacky','bouron']
for index,i in enumerate(a):
print(index,i)
#输出
0 jerry
1 jacky
2 bouron
元组（不可变列表）
创建元组：
ages = (11,22,33,44,55) 或 ages = tuple((11,22,33,44,55))
基本操作：
· 索引
· 切片
· 循环
· 长度
· 包含
lass tuple(object): """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. """ def count(self, value): # real signature unknown; restored from __doc__ """ T.count(value) -> integer -- return number of occurrences of value """ return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ T.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __init__(self, seq=()): # known special case of tuple.__init__ """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass def __mul__(self, n): # real signature unknown; restored from __doc__ """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ T.__sizeof__() -- size of T in memory, in bytes """ pass tuple
字典（无序）
创建字典：
id_db = {
1234567890:{
'name':"Tian si han",
'age':22,
'addr':'changzhou'
},
9876543210:{
'name':'Tian si nuan',
'age':'23',
'addr':'changzhou'
}
}
print(id_db)
#输出
{1234567890: {'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}, 9876543210: {'age': '23', 'addr': 'changzhou', 'name': 'Tian si nuan'}}
常用操作:
· 索引
# 查找 （最安全的获取方法）
print(id_db[1234567890].get('name'))
# 输出
Tian si han
print(id_db[1234567890].get('job'))
# 输出
None
· 新增
#添加元素
id_db[1234567890]['qq_num'] = 75298335
print(id_db[1234567890])
#输出
{'addr': 'changzhou', 'qq_num': 75298335, 'name': 'Tian si han', 'age': 22}
· 删除
#删除元素
id_db[9876543210].pop("addr")
print(id_db[9876543210])
#输出
{'name': 'Tian si nuan', 'age': '23'}
· 更改
#更改元素
id_db[9876543210]['name'] = "Tian si leng"
print(id_db[9876543210])
#输出
{'age': '23', 'name': 'Tian si leng'}
· 键、值、键值对
· 循环
· 长度
class dict(object): """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) """ def clear(self): # real signature unknown; restored from __doc__ """ 清除内容 """ """ D.clear() -> None. Remove all items from D. """ pass def copy(self): # real signature unknown; restored from __doc__ """ 浅拷贝 """ """ D.copy() -> a shallow copy of D """ pass @staticmethod # known case def fromkeys(S, v=None): # real signature unknown; restored from __doc__ """ dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v. v defaults to None. """ pass def get(self, k, d=None): # real signature unknown; restored from __doc__ """ 根据key获取值，d是默认值 """ """ D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """ pass def has_key(self, k): # real signature unknown; restored from __doc__ """ 是否有key """ """ D.has_key(k) -> True if D has a key k, else False """ return False def items(self): # real signature unknown; restored from __doc__ """ 所有项的列表形式 """ """ D.items() -> list of D's (key, value) pairs, as 2-tuples """ return [] def iteritems(self): # real signature unknown; restored from __doc__ """ 项可迭代 """ """ D.iteritems() -> an iterator over the (key, value) items of D """ pass def iterkeys(self): # real signature unknown; restored from __doc__ """ key可迭代 """ """ D.iterkeys() -> an iterator over the keys of D """ pass def itervalues(self): # real signature unknown; restored from __doc__ """ value可迭代 """ """ D.itervalues() -> an iterator over the values of D """ pass def keys(self): # real signature unknown; restored from __doc__ """ 所有的key列表 """ """ D.keys() -> list of D's keys """ return [] def pop(self, k, d=None): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.pop(k[,d]) -> v, remove specified key and return the corresponding value. If key is not found, d is returned if given, otherwise KeyError is raised """ pass def popitem(self): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.popitem() -> (k, v), remove and return some (key, value) pair as a 2-tuple; but raise KeyError if D is empty. """ pass def setdefault(self, k, d=None): # real signature unknown; restored from __doc__ """ 如果key不存在，则创建，如果存在，则返回已存在的值且不修改 """ """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """ pass def update(self, E=None, **F): # known special case of dict.update """ 更新 {'name':'alex', 'age': 18000} [('name','sbsbsb'),] """ """ D.update([E, ]**F) -> None. Update D from dict/iterable E and F. If E present and has a .keys() method, does: for k in E: D[k] = E[k] If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k] """ pass def values(self): # real signature unknown; restored from __doc__ """ 所有的值 """ """ D.values() -> list of D's values """ return [] def viewitems(self): # real signature unknown; restored from __doc__ """ 所有项，只是将内容保存至view对象中 """ """ D.viewitems() -> a set-like object providing a view on D's items """ pass def viewkeys(self): # real signature unknown; restored from __doc__ """ D.viewkeys() -> a set-like object providing a view on D's keys """ pass def viewvalues(self): # real signature unknown; restored from __doc__ """ D.viewvalues() -> an object providing a view on D's values """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __contains__(self, k): # real signature unknown; restored from __doc__ """ D.__contains__(k) -> True if D has a key k, else False """ return False def __delitem__(self, y): # real signature unknown; restored from __doc__ """ x.__delitem__(y) <==> del x[y] """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __init__(self, seq=None, **kwargs): # known special case of dict.__init__ """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ D.__sizeof__() -> size of D in memory, in bytes """ pass __hash__ = None dict
PS：循环，range，continue和break
#把字典变成一个元组（列表） 一般不用
print(id_db.items())
#输出
dict_items([(1234567890, {'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}), (9876543210, {'age': '23', 'addr': 'changzhou', 'name': 'Tian si nuan'})])
#------------------------------------------------------------------------------------------------
#打印字典里所有的vlave 一般不用
print(id_db.values())
#输出
dict_values([{'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}, {'age': '23', 'addr': 'changzhou', 'name': 'Tian si nuan'}])
#-----------------------------------------------------------------------------------------------
#打印字典里所有的key值
print(id_db.keys())
#输出
dict_keys([1234567890, 9876543210])
#-----------------------------------------------------------------------------------------------
#取一个key，如果存在就输出这个key的值
print(id_db.setdefault(1234567890))
#输出
{'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}
#----------------------------------------------------------------------------------------------
#取一个key，如果不存在就设置一个key的值 输出：hahah
print(id_db.setdefault(1345678902,"hahah"))
#输出
hahah
#----------------------------------------------------------------------------------------------
#随机删除 一般不用
print(id_db.popitem())
#输出
(1234567890, {'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'})
#----------------------------------------------------------------------------------------------
#高效循环
for key in id_db:
print(key,id_db[key])
#输出
1234567890 {'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}
9876543210 {'age': '23', 'addr': 'changzhou', 'name': 'Tian si nuan'}
#----------------------------------------------------------------------------------------------
#取值
v = id_db.get(1234567890)
print(v)
#输出
{'age': 22, 'addr': 'changzhou', 'name': 'Tian si han'}
y = id_db.get(111111111)
print(y)
#输出
None
#-------------------------------------------------------------------------------------------
dic2 = {
'name':"bourbon",
1234567890:{
'name':"Tian si han",
'age':23,
'addr':"changzhou"
},
}
id_db.update(dic2)
print(id_db)
#输出
{1234567890: {'age': 23, 'addr': 'changzhou', 'name': 'Tian si han'}, 9876543210: {'age': '23', 'addr': 'changzhou', 'name': 'Tian si nuan'}, 'name': 'bourbon'}
