int类(整数)
所有方法
>>> dir(int) [‘__abs__‘, ‘__add__‘, ‘__and__‘, ‘__clas s__‘, ‘__cmp__‘, ‘__coerce__‘, ‘__delattr__‘, ‘__div__‘, ‘__divmod__‘, ‘__doc__‘, ‘__float__‘, ‘__floordiv__‘, ‘__format__‘, ‘__getattribute__‘, ‘__getnewargs__‘, ‘__hash__‘, ‘__hex__‘, ‘__index__‘, ‘__init__‘, ‘__int__‘, ‘__invert__‘, ‘__long__‘, ‘__lshift__‘, ‘__mod__‘, ‘__mul__‘, ‘__neg__‘, ‘__new__‘, ‘__nonzero__‘, ‘__oct__‘, ‘__or__‘, ‘__pos__‘, ‘__pow__‘, ‘__radd__‘, ‘__rand__‘, ‘__rdiv__‘, ‘__rdivmod__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rfloordiv__‘, ‘__rlshift__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__ror__‘, ‘__rpow__‘, ‘__rrshift__‘, ‘__rshift__‘, ‘__rsub__‘, ‘__rtruediv__‘, ‘__rxor__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__truediv__‘, ‘__trunc__‘, ‘__xor__‘, ‘bit_length‘, ‘conjugate‘, ‘denominator‘, ‘imag‘, ‘numerator‘, ‘real‘]
源码
1 class int(object): 2 """ 3 int(x=0) -> int or long 4 int(x, base=10) -> int or long 5 6 Convert a number or string to an integer, or return 0 if no arguments 7 are given. If x is floating point, the conversion truncates towards zero. 8 If x is outside the integer range, the function returns a long instead. 9 10 If x is not a number or if base is given, then x must be a string or 11 Unicode object representing an integer literal in the given base. The 12 literal can be preceded by ‘+‘ or ‘-‘ and be surrounded by whitespace. 13 The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to 14 interpret the base from the string as an integer literal. 15 >>> int(‘0b100‘, base=0) 16 4 17 """ 18 def bit_length(self): # real signature unknown; restored from __doc__ 19 """返回表示该数字时所用的最小位数 20 int.bit_length() -> int 21 22 Number of bits necessary to represent self in binary. 23 >>> bin(37) 24 ‘0b100101‘ 25 >>> (37).bit_length() 26 6 27 """ 28 return 0 29 30 def conjugate(self, *args, **kwargs): # real signature unknown 31 """返回一个复数的共轭复数 32 Returns self, the complex conjugate of any int. """ 33 pass 34 35 def __abs__(self): # real signature unknown; restored from __doc__ 36 """ 返回绝对值 37 x.__abs__() <==> abs(x) """ 38 pass 39 40 def __add__(self, y): # real signature unknown; restored from __doc__ 41 """ 返回两个数的和 42 x.__add__(y) <==> x+y """ 43 pass 44 45 def __and__(self, y): # real signature unknown; restored from __doc__ 46 """ 返回两个数按位与的结果 47 x.__and__(y) <==> x&y """ 48 pass 49 50 def __cmp__(self, y): # real signature unknown; restored from __doc__ 51 """返回两个数比较的结果,参数从左至右(a,b),a>b返回1,a<b返回-1,a=b返回0 52 x.__cmp__(y) <==> cmp(x,y) """ 53 pass 54 55 def __coerce__(self, y): # real signature unknown; restored from __doc__ 56 """a.__coerce__(b),强制返回一个元组(a,b) 57 x.__coerce__(y) <==> coerce(x, y) """ 58 pass 59 60 def __divmod__(self, y): # real signature unknown; restored from __doc__ 61 """ 相除,得到商和余数组成的元组 62 x.__divmod__(y) <==> divmod(x, y) """ 63 pass 64 65 def __div__(self, y): # real signature unknown; restored from __doc__ 66 """返回两数相除的商 67 x.__div__(y) <==> x/y """ 68 pass 69 70 def __float__(self): # real signature unknown; restored from __doc__ 71 """将数据类型强制转换为float 72 x.__float__() <==> float(x) """ 73 pass 74 75 def __floordiv__(self, y): # real signature unknown; restored from __doc__ 76 """ 不保留小数点后的小数除法,也可以用‘//’来表示:a//b,我们亲切地称之为“地板除”!!! 77 x.__floordiv__(y) <==> x//y """ 78 pass 79 80 def __format__(self, *args, **kwargs): # real signature unknown 81 """ 格式化""" 82 pass 83 84 def __getattribute__(self, name): # real signature unknown; restored from __doc__ 85 """无条件被调用,通过实例访问属性 86 x.__getattribute__(‘name‘) <==> x.name """ 87 pass 88 89 def __getnewargs__(self, *args, **kwargs): # real signature unknown 90 """ 内部调用 __new__方法或创建对象时传入参数使用 """ 91 pass 92 93 def __hash__(self): # real signature unknown; restored from __doc__ 94 """ 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 95 x.__hash__() <==> hash(x) """ 96 pass 97 98 def __hex__(self): # real signature unknown; restored from __doc__ 99 """ 返回当前数的 十六进制 表示 100 x.__hex__() <==> hex(x) """ 101 pass 102 103 def __index__(self): # real signature unknown; restored from __doc__ 104 """ 用于切片,对数字无意义 105 x[y:z] <==> x[y.__index__():z.__index__()] """ 106 pass 107 108 def __init__(self, x, base=10): # known special case of int.__init__ 109 """构造函数 110 int(x=0) -> int or long 111 int(x, base=10) -> int or long 112 113 Convert a number or string to an integer, or return 0 if no arguments 114 are given. If x is floating point, the conversion truncates towards zero. 115 If x is outside the integer range, the function returns a long instead. 116 117 If x is not a number or if base is given, then x must be a string or 118 Unicode object representing an integer literal in the given base. The 119 literal can be preceded by ‘+‘ or ‘-‘ and be surrounded by whitespace. 120 The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to 121 interpret the base from the string as an integer literal. 122 >>> int(‘0b100‘, base=0) 123 4 124 # (copied from class doc) 125 """ 126 pass 127 128 def __int__(self): # real signature unknown; restored from __doc__ 129 """ 转换为整数 130 x.__int__() <==> int(x) """ 131 pass 132 133 def __invert__(self): # real signature unknown; restored from __doc__ 134 """按位求反 135 x.__invert__() <==> ~x """ 136 pass 137 138 def __long__(self): # real signature unknown; restored from __doc__ 139 """转换为长整数 140 x.__long__() <==> long(x) """ 141 pass 142 143 def __lshift__(self, y): # real signature unknown; restored from __doc__ 144 """ 左移,相对二进制的操作 145 x.__lshift__(y) <==> x<<y """ 146 pass 147 148 def __mod__(self, y): # real signature unknown; restored from __doc__ 149 """ 取余 150 x.__mod__(y) <==> x%y """ 151 pass 152 153 def __mul__(self, y): # real signature unknown; restored from __doc__ 154 """ 返回两数相乘的积 155 x.__mul__(y) <==> x*y """ 156 pass 157 158 def __neg__(self): # real signature unknown; restored from __doc__ 159 """ 返回一个数的负数,个人觉得和相反数没差 160 x.__neg__() <==> -x """ 161 pass 162 163 @staticmethod # known case of __new__ 164 def __new__(S, *more): # real signature unknown; restored from __doc__ 165 """ 创建一个int类的新对象 166 T.__new__(S, ...) -> a new object with type S, a subtype of T """ 167 pass 168 169 def __nonzero__(self): # real signature unknown; restored from __doc__ 170 """ 判断一个数是不是0 171 x.__nonzero__() <==> x != 0 """ 172 pass 173 174 def __oct__(self): # real signature unknown; restored from __doc__ 175 """ 返回该值的 八进制 表示 176 x.__oct__() <==> oct(x) """ 177 pass 178 179 def __or__(self, y): # real signature unknown; restored from __doc__ 180 """ 位运算,或,针对二进制数 181 x.__or__(y) <==> x|y """ 182 pass 183 184 def __pos__(self): # real signature unknown; restored from __doc__ 185 """ 并没什么卵用,说是a.__pos__(),会返回一个+a,但是不管输入整数还是负数,返回值都是他本身,感觉歪果仁真有幽默感 186 x.__pos__() <==> +x """ 187 pass 188 189 def __pow__(self, y, z=None): # real signature unknown; restored from __doc__ 190 """ 幂,次方 191 x.__pow__(y[, z]) <==> pow(x, y[, z]) """ 192 pass 193 194 def __radd__(self, y): # real signature unknown; restored from __doc__ 195 """x.__radd__(y) <==> y+x """ 196 pass 197 198 def __rand__(self, y): # real signature unknown; restored from __doc__ 199 """x.__rand__(y) <==> y&x """ 200 pass 201 202 def __rdivmod__(self, y): # real signature unknown; restored from __doc__ 203 """ x.__rdivmod__(y) <==> divmod(y, x) """ 204 pass 205 206 def __rdiv__(self, y): # real signature unknown; restored from __doc__ 207 """ x.__rdiv__(y) <==> y/x """ 208 pass 209 210 def __repr__(self): # real signature unknown; restored from __doc__ 211 """ 转化为解释器可读取的形式 212 x.__repr__() <==> repr(x) """ 213 pass 214 215 def __rfloordiv__(self, y): # real signature unknown; restored from __doc__ 216 """ 217 x.__rfloordiv__(y) <==> y//x """ 218 pass 219 220 def __rlshift__(self, y): # real signature unknown; restored from __doc__ 221 """ x.__rlshift__(y) <==> y<<x """ 222 pass 223 224 def __rmod__(self, y): # real signature unknown; restored from __doc__ 225 """ x.__rmod__(y) <==> y%x """ 226 pass 227 228 def __rmul__(self, y): # real signature unknown; restored from __doc__ 229 """ x.__rmul__(y) <==> y*x """ 230 pass 231 232 def __ror__(self, y): # real signature unknown; restored from __doc__ 233 """ x.__ror__(y) <==> y|x """ 234 pass 235 236 def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__ 237 """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ 238 pass 239 240 def __rrshift__(self, y): # real signature unknown; restored from __doc__ 241 """ x.__rrshift__(y) <==> y>>x """ 242 pass 243 244 def __rshift__(self, y): # real signature unknown; restored from __doc__ 245 """ x.__rshift__(y) <==> x>>y """ 246 pass 247 248 def __rsub__(self, y): # real signature unknown; restored from __doc__ 249 """ x.__rsub__(y) <==> y-x """ 250 pass 251 252 def __rtruediv__(self, y): # real signature unknown; restored from __doc__ 253 """ x.__rtruediv__(y) <==> y/x """ 254 pass 255 256 def __rxor__(self, y): # real signature unknown; restored from __doc__ 257 """ x.__rxor__(y) <==> y^x """ 258 pass 259 260 def __str__(self): # real signature unknown; restored from __doc__ 261 """ 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 262 x.__str__() <==> str(x) """ 263 pass 264 265 def __sub__(self, y): # real signature unknown; restored from __doc__ 266 """ 返回两数相减的差 267 x.__sub__(y) <==> x-y """ 268 pass 269 270 def __truediv__(self, y): # real signature unknown; restored from __doc__ 271 """返回两数相除的商,这里的除是精确的除法,不会省略小数点后的值 272 x.__truediv__(y) <==> x/y """ 273 pass 274 275 def __trunc__(self, *args, **kwargs): # real signature unknown 276 """返回数值被截取为整形的值,在整形中无意义 277 Truncating an Integral returns itself. """ 278 pass 279 280 def __xor__(self, y): # real signature unknown; restored from __doc__ 281 """ 按位异或 282 x.__xor__(y) <==> x^y """ 283 pass 284 285 denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 286 """ 分母 = 1 """ 287 """the denominator of a rational number in lowest terms""" 288 289 imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 290 """ 虚数,无意义 """ 291 """the imaginary part of a complex number""" 292 293 numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 294 """ 分子 = 数字大小 """ 295 """the numerator of a rational number in lowest terms""" 296 297 real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 298 """ 实数,无意义 """ 299 """the real part of a complex number""" 300 301 int Code
只是在前面多了一个‘r‘的比如and,变成了rand,在这里统一总结,就是参数的顺序从右到左反过来了。比如原本的a.__div__(b)是a/b,但是a.__rdiv__(b)的表示的就是b/a。
在int类中,常用的方法:
(1)__cmp__:比较两个数的大小
(2)__neg__/__ads__;去相反数、取绝对值
a = -13 b = 20 n = a.__neg__() print(n) m = b.__neg__() print(m) k = a.__abs__() print(k) h = b.__abs__() print(h) 输出: 13 -20 13 20
(3)__divmod__;返回两个数相除的商和余数组成的元组(商,余数) 应用:显示数据分页
a = 102 b = 10 n = a.__divmod__(b) print(n) 输出 (10,2)
long类(长整形)
所有方法:
>>> dir(long) [‘__abs__‘, ‘__add__‘, ‘__and__‘, ‘__class__‘, ‘__cmp__‘, ‘__coerce__‘, ‘__delattr__‘, ‘__div__‘, ‘__divmod__‘, ‘__doc__‘, ‘__float__‘, ‘__floordiv__‘, ‘__format__‘, ‘__getattribute__‘, ‘__getnewargs__‘, ‘__hash__‘, ‘__hex__‘, ‘__index__‘, ‘__init__‘, ‘__int__‘, ‘__invert__‘, ‘__long__‘, ‘__lshift__‘, ‘__mod__‘, ‘__mul__‘, ‘__neg__‘, ‘__new__‘, ‘__nonzero__‘, ‘__oct__‘, ‘__or__‘, ‘__pos__‘, ‘__pow__‘, ‘__radd__‘, ‘__rand__‘, ‘__rdiv__‘, ‘__rdivmod__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rfloordiv__‘, ‘__rlshift__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__ror__‘, ‘__rpow__‘, ‘__rrshift__‘, ‘__rshift__‘, ‘__rsub__‘, ‘__rtruediv__‘, ‘__rxor__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__truediv__‘, ‘__trunc__‘, ‘__xor__‘, ‘bit_length‘, ‘conjugate‘, ‘denominator‘, ‘imag‘, ‘numerator‘, ‘real‘]
fioat类(浮点型)
所有方法:
>>> dir(float) [‘__abs__‘, ‘__add__‘, ‘__class__‘, ‘__coerce__‘, ‘__delattr__‘, ‘__div__‘, ‘__divmod__‘, ‘__doc__‘, ‘__eq__‘, ‘__float__‘, ‘__floordiv__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getformat__‘, ‘__getnewargs__‘, ‘__gt__‘, ‘__hash__‘, ‘__init__‘, ‘__int__‘, ‘__le__‘, ‘__long__‘, ‘__lt__‘, ‘__mod__‘, ‘__mul__‘, ‘__ne__‘, ‘__neg__‘, ‘__new__‘, ‘__nonzero__‘, ‘__pos__‘, ‘__pow__‘, ‘__radd__‘, ‘__rdiv__‘, ‘__rdivmod__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rfloordiv__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__rpow__‘, ‘__rsub__‘, ‘__rtruediv__‘, ‘__setattr__‘, ‘__setformat__‘, ‘__sizeof__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__truediv__‘, ‘__trunc__‘, ‘as_integer_ratio‘, ‘conjugate‘, ‘fromhex‘, ‘hex‘, ‘imag‘, ‘is_integer‘, ‘real‘]
str类(字符串)
所有方法
>>> dir(str) [‘__add__‘, ‘__class__‘, ‘__contains__‘, ‘__delattr__‘, ‘__doc__‘, ‘__eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getitem__‘, ‘__getnewargs__‘, ‘__getslice__‘, ‘__gt__‘, ‘__hash__‘, ‘__init__‘, ‘__le__‘, ‘__len__‘, ‘__lt__‘, ‘__mod__‘, ‘__mul__‘, ‘__ne__‘, ‘__new__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__subclasshook__‘, ‘_formatter_field_name_split‘, ‘_formatter_parser‘, ‘capitalize‘, ‘center‘, ‘count‘, ‘decode‘, ‘encode‘, ‘endswith‘, ‘expandtabs‘, ‘find‘, ‘format‘, ‘index‘, ‘isalnum‘, ‘isalpha‘, ‘isdigit‘, ‘islower‘, ‘isspace‘, ‘istitle‘, ‘isupper‘, ‘join‘, ‘ljust‘, ‘lower‘, ‘lstrip‘, ‘partition‘, ‘replace‘, ‘rfind‘, ‘rindex‘, ‘rjust‘, ‘rpartition‘, ‘rsplit‘, ‘rstrip‘, ‘split‘, ‘splitlines‘, ‘startswith‘, ‘strip‘, ‘swapcase‘, ‘title‘, ‘translate‘, ‘upper‘, ‘zfill‘]
源码
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,则异常 """ """ 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,则返回-1 """ 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): """是否空格 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): """是否标题 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): """是否大写 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 str str Code
str类中常见的方法实例:
(1)capitalize:将首字母大写
a1 = "alex" ret = a1.capitalize() print(ret)
(2)center/ljust/rjust:固定字符串长度,居中/居左/居右
a1 = "alex" ret = a1.center(10,"*") print(ret) a1 = "alex" ret = a1.ljust(10,"*") print(ret) a1 = "alex" ret = a1.rjust(10,"*") print(ret) 输出 ***alex*** alex****** ******alex
(3)count:子序列个数,用来统计一个字符串中包含子序列的个数。
str1 = ‘hello,Eva.Have a nice day‘ r = str1.count("a") print(r) 输出 4
(4)encode/decode:编码/解码
(5)endswith:是否以...(子串)结尾。这里的子串依然可以是一个或多个字符。
str1 = ‘hello,Eva.Have a nice day‘ r = str1.endswith("day") print(r) 输出 True
(6)expandtabs:将tab转换成空格,默认一个tab转换成8个空格。
name = " Eva" b = name.expandtabs() print(b)
(7)find:返回字符串中第一个子序列的下标。
rfind:和find用法一样,只是它是从右向左查找
index:和find的左右一致,只是find找不到的时候会返回-1,而index找不到的时候会报错
(8)format:各种格式化,动态参数。
s = "hello {0}, age {1}" new1 = s.format("alex", 19) print(new1) 输出 hello alex, age 19
(9)isalnum/isalpha/isdigit/isspace/islower/istitle/isupper:是否是字母或数字/是否字母/是否数字/是否空格/是否小写/是否标题/是否全大写,总之都是一些判断的方 法,返回的不是True就是False。
(10)partition/split:这两个方法都用来分割。
partition会将指定的子串串提取并将子串两侧内容分割,只匹配一次,并返回元祖;
split会根据指定子串,将整个字符串所有匹配的子串匹配到并剔除,将其他内容分割,返回数组。
food = "apple,banana,chocolate" d = food.split(",") print(d) s = food.partition(",") print(s) 输出 [‘apple‘, ‘banana‘, ‘chocolate‘] (‘apple‘, ‘,‘, ‘banana,chocolate‘)
(11)replace:替换。会替换字符串中所有符合条件的子串
str1 = ‘I\‘m Rita,Do you remember,Rita?‘ z = str1.replace(‘Rita‘,‘Eva‘) print(z) 输出 I‘m Eva,Do you remember,Eva?
(12)swapcase:大写变小写,小写变大写
str1 = ‘I\‘m Rita,Do you remember,Rita?‘ z = str1.swapcase() print(z) 输出 i‘M rITA,dO YOU REMEMBER,rITA?
list类 (列表)
所有方法
>>> dir(list) [‘__add__‘, ‘__class__‘, ‘__contains__‘, ‘__delattr__‘, ‘__delitem__‘, ‘__delslice__‘, ‘__doc__‘, ‘__eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getitem__‘, ‘__getslice__‘, ‘__gt__‘, ‘__hash__‘, ‘__iadd__‘, ‘__imul__‘, ‘__init__‘, ‘__iter__‘, ‘__le__‘, ‘__len__‘, ‘__lt__‘, ‘__mul__‘, ‘__ne__‘, ‘__new__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__reversed__‘, ‘__rmul__‘, ‘__setattr__‘, ‘__setitem__‘, ‘__setslice__‘, ‘__sizeof__‘, ‘__str__‘, ‘__subclasshook__‘, ‘append‘, ‘count‘, ‘extend‘, ‘index‘, ‘insert‘, ‘pop‘, ‘remove‘, ‘reverse‘, ‘sort‘]
源码
class list(object): """ list() -> new empty list list(iterable) -> new list initialized from iterable‘s items """在数组的末尾新增一项 def append(self, p_object): # real signature unknown; restored from __doc__ """ L.append(object) -- append object to end """ pass def count(self, value): # real signature unknown; restored from __doc__ """ 查看lst中某一项出现的次数 L.count(value) -> integer -- return number of occurrences of value """ return 0 def extend(self, iterable): # real signature unknown; restored from __doc__ """将原列表与其他列表扩展成新列表 L.extend(iterable) -- extend list by appending elements from the iterable """ pass def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """返回列表中第一个匹配项的下标,找不到会报错 L.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def insert(self, index, p_object): # real signature unknown; restored from __doc__ """在指定位置插入项 L.insert(index, object) -- insert object before index """ pass def pop(self, index=None): # real signature unknown; restored from __doc__ """返回指定位置的值,并将其从列表中删除。默认对末尾项操作 L.pop([index]) -> item -- remove and return item at index (default last). Raises IndexError if list is empty or index is out of range. """ pass def remove(self, value): # real signature unknown; restored from __doc__ """从列表中移除第一个符合与指定值相等的项 L.remove(value) -- remove first occurrence of value. Raises ValueError if the value is not present. """ pass def reverse(self): # real signature unknown; restored from __doc__ """列表反转 L.reverse() -- reverse *IN PLACE* """ pass def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__ """排序,数字、字符串按照ASCII,中文按照unicode从小到大排序。 L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*; cmp(x, y) -> -1, 0, 1 """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ 字符串拼接 x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ 判断列表中是否包含某一项 x.__contains__(y) <==> y in x """ pass def __delitem__(self, y): # real signature unknown; restored from __doc__ """删除列表中指定下标的项 x.__delitem__(y) <==> del x[y] """ pass def __delslice__(self, i, j): # real signature unknown; restored from __doc__ """删除指定下标之间的内容,向下包含 x.__delslice__(i, j) <==> del x[i:j] Use of negative indices is not supported. """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ 判断两个列表是否相等 x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ 无条件被调用,通过实例访问属性。 x.__getattribute__(‘name‘) <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ 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 __iadd__(self, y): # real signature unknown; restored from __doc__ """ x.__iadd__(y) <==> x+=y """ pass def __imul__(self, y): # real signature unknown; restored from __doc__ """ x.__imul__(y) <==> x*=y """ pass def __init__(self, seq=()): # known special case of list.__init__ """ list() -> new empty list list(iterable) -> new list initialized from iterable‘s items # (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 __reversed__(self): # real signature unknown; restored from __doc__ """ L.__reversed__() -- return a reverse iterator over the list """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__ """ x.__setslice__(i, j, y) <==> x[i:j]=y Use of negative indices is not supported. """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ L.__sizeof__() -- size of L in memory, in bytes """ pass __hash__ = None list list Code
一般常用的list类的方法
(1)append:向列表中添加项
insert:在列表的指定位置加入值
extend:列表的扩展;
name_list = ["eirc","alex","tony"] name_list.append(‘seven‘) print(name_list) # 运算结果: # [‘eirc‘, ‘alex‘, ‘tony‘, ‘seven‘] name_list.insert(1,‘hello‘) print(name_list) # 运算结果: # [‘eirc‘, ‘hello‘, ‘alex‘, ‘tony‘, 11, 22, 33, 44]
name_list = ["eirc","alex","tony"]temp = [11,22,33,44]name_list.extend(temp)print(name_list)输出[‘eirc‘, ‘alex‘, ‘tony‘, 11, 22, 33, 44]
2)index:返回列表中第一个匹配项的下标
__contain__:查看列表中是否包含某一项
count:查看列表中某一项出现的次数
name_list = ["eirc","alex","tony"] temp = [11,22,33,44] name_list.extend(temp) print(name_list.index(‘alex‘)) 运算结果: 1
3)pop:删除并返回指定下标的值,默认为列表的最后一个值
remove:删除列表中与指定值匹配的第一个值
__delitem__:删除指定下标的值
__delslice__:删除指定下标区域内的所有值,下标向下包含
name_list = ["eirc","alex","tony"] a1 = name_list.pop() print(a1) name_list = [‘eirc‘, ‘hello‘,‘alex‘, ‘alex‘, ‘tony‘] name_list.remove(‘alex‘) print(name_list) 输出 tony [‘eirc‘, ‘hello‘, ‘alex‘, ‘tony‘, 11, 22, 33, 44]
(4)reverse:列表反转,这个反转并没有什么编码顺序,就是单纯的把原来的列表从头到尾调转过来而已。
sort:排序,数字、字符串按照ASCII,中文按照unicode从小到大排序。
name_list = [‘eirc‘, ‘hello‘,‘alex‘, ‘alex‘, ‘tony‘] name_list.reverse() print(name_list) name_list = [11,44,55,66,77,99,33] name_list.sort() print(name_list) 输出 [‘tony‘, ‘alex‘, ‘alex‘, ‘hello‘, ‘eirc‘] [11, 33, 44, 55, 66, 77, 99]
tupie类(元组)
所有方法
>>> dir(tuple) [‘__add__‘, ‘__class__‘, ‘__contains__‘, ‘__delattr__‘, ‘__doc__‘, ‘__eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getitem__‘, ‘__getnewargs__‘, ‘__getslice__‘, ‘__gt__‘, ‘__hash__‘, ‘__init__‘, ‘__iter__‘, ‘__le__‘, ‘__len__‘, ‘__lt__‘, ‘__mul__‘, ‘__ne__‘, ‘__new__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rmul__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__subclasshook__‘, ‘count‘, ‘index‘]
tuple和list基本相同,但是tuple是不可修改的。所以也就没有添加,删除,修改等方法。但是count,__contain__等方法还是存在的,和list中用法相同
dict类(字典)
所有方法
dir(dict) [‘__class__‘, ‘__cmp__‘, ‘__contains__‘, ‘__delattr__‘, ‘__delitem__‘, ‘__doc__‘, ‘__eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getitem__‘, ‘__gt__‘, ‘__hash__‘, ‘__init__‘, ‘__iter__‘, ‘__le__‘, ‘__len__‘, ‘__lt__‘, ‘__ne__‘, ‘__new__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__setattr__‘, ‘__setitem__‘, ‘__sizeof__‘, ‘__str__‘, ‘__subclasshook__‘, ‘clear‘, ‘copy‘, ‘fromkeys‘, ‘get‘, ‘has_key‘, ‘items‘, ‘iteritems‘, ‘iterkeys‘, ‘itervalues‘, ‘keys‘, ‘pop‘, ‘popitem‘, ‘setdefault‘, ‘update‘, ‘values‘, ‘viewitems‘, ‘viewkeys‘, ‘viewvalues‘]
源码
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 dict code
字典的特性,和list不同,字典是无序的,它依靠key和value之间的联系进行索引,由于这种特殊的索引方式,字典中不可以有重复的key。
一些常用的dict方法
(1)keys/values/items:取所有字典的key/取所有字典的value/取所有字典的key,value
dic = {‘name‘:‘eva‘,‘age‘:20} print(dic.keys()) print(dic.values()) print(dic.items()) 输出 dict_keys([‘name‘, ‘age‘]) dict_values([‘eva‘, 20]) dict_items([(‘name‘, ‘eva‘), (‘age‘, 20)])
(2)已知key的情况下,获取value的值时可以使用‘字典名[key值]’的方法,for k,v in dic.items()的方法
get:字典名[key值]的方式有一点弊端,那就是当key值不存在的时候会报错,这个时候我们使用get方法,可以避免报错的情况
dic = {‘name‘:‘Eva‘,‘age‘:18} n = dic.get("name") print(n) 输出 Eva
(3)clear:清空字典
dic = {‘name‘:‘eva‘,‘age‘:20} dic.clear() print(dic) 输出 {}
(4)pop:根据指定的key删除一组数据
popitem:随机的删除一组数据
dic = {‘name‘:‘eva‘,‘age‘:20,‘ser‘:3} s = dic.pop("age") print(s) a = dic.popitem() #随机删除一组数据 print(a) 输出 20 (‘name‘, ‘eva‘)
(5)setdefault:dic.setdefault[key1],key1存在,则返回value1,不存在,则自动创建value = ‘None‘
dic = {‘name‘:‘eva‘,‘age‘:20,‘ser‘:3} z = dic.setdefault(‘name‘) print(z) s = dic.setdefault(‘sad‘) print(s) 输出 eva None
(6)update:dict1.update(dict2),判断dict2中的每一个key在dict1中是否存在,
存在:就将dict1中的value更新成dict2中的,不存在:将key和value都复制过去
dic1 = {‘name‘:‘Eva‘,‘age‘:18,‘ser‘:3} dic2 = {‘age‘: 18, ‘name‘: ‘Eva‘,‘gender‘:‘female‘} dic1.update(dic2) print(dic1) 输出 {‘gender‘: ‘female‘, ‘name‘: ‘Eva‘, ‘ser‘: 3, ‘age‘: 18}
(7)fromkeys:可以通过list创建一个字典,
dict.fromkeys([1,2,3],‘test‘),可以创建一个字典,但是如果a.fromkeys([1,2,3],[]},创建的字典的值都是一个空列表,那么其中一个列表的值发生了变化,所有的列表
都会跟着发生变化
set集合
set是一个无序且不重复的元素集合
所有方法
[‘__and__‘, ‘__class__‘, ‘__cmp__‘, ‘__contains__‘, ‘__delattr__‘, ‘__doc__‘, ‘_ _eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__gt__‘, ‘__hash__‘, ‘__ian d__‘, ‘__init__‘, ‘__ior__‘, ‘__isub__‘, ‘__iter__‘, ‘__ixor__‘, ‘__le__‘, ‘__le n__‘, ‘__lt__‘, ‘__ne__‘, ‘__new__‘, ‘__or__‘, ‘__rand__‘, ‘__reduce__‘, ‘__redu ce_ex__‘, ‘__repr__‘, ‘__ror__‘, ‘__rsub__‘, ‘__rxor__‘, ‘__setattr__‘, ‘__sizeo f__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__xor__‘, ‘add‘, ‘clear‘, ‘copy ‘, ‘difference‘, ‘difference_update‘, ‘discard‘, ‘intersection‘, ‘intersection_u pdate‘, ‘isdisjoint‘, ‘issubset‘, ‘issuperset‘, ‘pop‘, ‘remove‘, ‘symmetric_diff erence‘, ‘symmetric_difference_update‘, ‘union‘, ‘update‘]
源码
class set(object): """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. """ def add(self, *args, **kwargs): # real signature unknown """ 添加 """ """ Add an element to a set. This has no effect if the element is already present. """ pass def clear(self, *args, **kwargs): # real signature unknown """ Remove all elements from this set. """ pass def copy(self, *args, **kwargs): # real signature unknown """ Return a shallow copy of a set. """ pass def difference(self, *args, **kwargs): # real signature unknown """ Return the difference of two or more sets as a new set. (i.e. all elements that are in this set but not the others.) """ pass def difference_update(self, *args, **kwargs): # real signature unknown """ 删除当前set中的所有包含在 new set 里的元素 """ """ Remove all elements of another set from this set. """ pass def discard(self, *args, **kwargs): # real signature unknown """ 移除元素 """ """ Remove an element from a set if it is a member. If the element is not a member, do nothing. """ pass def intersection(self, *args, **kwargs): # real signature unknown """ 取交集,新创建一个set """ """ Return the intersection of two or more sets as a new set. (i.e. elements that are common to all of the sets.) """ pass def intersection_update(self, *args, **kwargs): # real signature unknown """ 取交集,修改原来set """ """ Update a set with the intersection of itself and another. """ pass def isdisjoint(self, *args, **kwargs): # real signature unknown """ 如果没有交集,返回true """ """ Return True if two sets have a null intersection. """ pass def issubset(self, *args, **kwargs): # real signature unknown """ 是否是子集 """ """ Report whether another set contains this set. """ pass def issuperset(self, *args, **kwargs): # real signature unknown """ 是否是父集 """ """ Report whether this set contains another set. """ pass def pop(self, *args, **kwargs): # real signature unknown """ 移除 """ """ Remove and return an arbitrary set element. Raises KeyError if the set is empty. """ pass def remove(self, *args, **kwargs): # real signature unknown """ 移除 """ """ Remove an element from a set; it must be a member. If the element is not a member, raise a KeyError. """ pass def symmetric_difference(self, *args, **kwargs): # real signature unknown """ 差集,创建新对象""" """ Return the symmetric difference of two sets as a new set. (i.e. all elements that are in exactly one of the sets.) """ pass def symmetric_difference_update(self, *args, **kwargs): # real signature unknown """ 差集,改变原来 """ """ Update a set with the symmetric difference of itself and another. """ pass def union(self, *args, **kwargs): # real signature unknown """ 并集 """ """ Return the union of sets as a new set. (i.e. all elements that are in either set.) """ pass def update(self, *args, **kwargs): # real signature unknown """ 更新 """ """ Update a set with the union of itself and others. """ pass def __and__(self, y): # real signature unknown; restored from __doc__ """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(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 __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 __iand__(self, y): # real signature unknown; restored from __doc__ """ x.__iand__(y) <==> x&=y """ pass def __init__(self, seq=()): # known special case of set.__init__ """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. # (copied from class doc) """ pass def __ior__(self, y): # real signature unknown; restored from __doc__ """ x.__ior__(y) <==> x|=y """ pass def __isub__(self, y): # real signature unknown; restored from __doc__ """ x.__isub__(y) <==> x-=y """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __ixor__(self, y): # real signature unknown; restored from __doc__ """ x.__ixor__(y) <==> x^=y """ 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 __or__(self, y): # real signature unknown; restored from __doc__ """ x.__or__(y) <==> x|y """ pass def __rand__(self, y): # real signature unknown; restored from __doc__ """ x.__rand__(y) <==> y&x """ pass def __reduce__(self, *args, **kwargs): # real signature unknown """ Return state information for pickling. """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __ror__(self, y): # real signature unknown; restored from __doc__ """ x.__ror__(y) <==> y|x """ pass def __rsub__(self, y): # real signature unknown; restored from __doc__ """ x.__rsub__(y) <==> y-x """ pass def __rxor__(self, y): # real signature unknown; restored from __doc__ """ x.__rxor__(y) <==> y^x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __sub__(self, y): # real signature unknown; restored from __doc__ """ x.__sub__(y) <==> x-y """ pass def __xor__(self, y): # real signature unknown; restored from __doc__ """ x.__xor__(y) <==> x^y """ pass __hash__ = None set
一些常用的方法处理set集合
(1)difference 找出集合中不存在的,并将其赋值给新变量
se = {11,22,33,44,} be = {22,33,55,66,} ret = se.difference(be) #找出se中存在be中不存在的集合,并将其赋值给新变量 print(ret) 运算结果: {11, 44}
(2)difference _update() 找到se中存在,be中不存在的集合,更新自己
se = {11,22,33,44,} be = {22,33,55,66,} ret = se.difference_update(be) #找到se中存在,be中不存在的集合,更新自己 print(se) 运算结果: {11, 44}
(3)intersection 交集
l1=[11,22,33] l2=[22,33,44] ret = list(set(l1).intersection(set(l2))) #交集 print(ret) 输出: [33, 22]
(4)symmetric_difference 对称交集
se = {11,22,33,44,} be = {22,33,55,66,} ret = se.symmetric_difference(be) #对称交集 print() 运算结果: {66, 11, 44, 55}
(5) union 并集
se = {11,22,33,44,} be = {22,33,55,66,} ret = se.union(be) # 并集 print(ret) 运算结果: {33, 66, 11, 44, 22, 55}
(6)discard 移除指定文件,不存在是不报错
remove移除元素,不存在会报错
se = {22,33,44,} ret = se.discard(11)#移除指定文件,不存在是不报错 print(ret) 运算结果: None se = {22,33,44,} ret = se.remove(11) #移除元素,不存在会报错 print(se)
(7)clear 清除集合
se = {22,33,44,} ret = se.clear() # 清除集合 print(se) 运算结果: set()
(8) add 增加
se = {22,33,44,} ret = se.add(35) # 增加 print(se) 运算结果: {33, 35, 44, 22}
(9)issubset 判断交集有是False,没有True
se = {22,33,44,} be = {22,33,55,66,} ret = se.issubset(be) #判断交集有是False,没有True print(ret) 运算结果: False