数据类型--数字
标准数据类型
在内存中存储的数据可以有多种类型。
例如，需要存储一些数字、字母、字符串、等一些数据时，就需要在内存中有相对应的存储类型标签。
Python有一些标准类型用于定义数据存储方法的操作。
Python有五个标准的数据类型：
Numbers（数字）
String（字符串）
List（列表）
Tuple（元组）
Dictionary（字典）
数字： 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
四种不同的数值类型
int（有符号整型）
long（长整型[也可以代表八进制和十六进制]）
float（浮点型）
complex（复数）
| int | long | float | complex |
|---|---|---|---|
| 10 | 51924361L | 0.0 | 3.14j |
| 100 | -0x19323L | 15.20 | 45.j |
| -786 | 0122L | -21.9 | 9.322e-36j |
| 080 | 0xDEFABCECBDAECBFBAEl | 32.3+e18 | .876j |
| -0490 | 535633629843L | -90. | -.6545+0J |
| -0x260 | -052318172735L | -32.54e100 | 3e+26J |
| 0x69 | -4721885298529L | 70.2-E12 | 4.53e-7j |
长整型也可以使用小写"L"，但是还是建议您使用大写"L"，避免与数字"1"混淆。Python使用"L"来显示长整型。
Python还支持复数，复数由实数部分和虚数部分构成，可以用a + bj,或者complex(a,b)表示， 复数的实部a和虚部b都是浮点型。
整形：
整数int表示的范围-2,147,483,648到2,147,483,647
赋值整形数字变量：
1 >>> num1=123 2 3 查看数字类型： 4 >>> type(123) 5 <type 'int'> 6 7 查看变量类型： 8 9 >>> type(num1) 10 <type 'int'>
长整型long
一般long的范围很大的话，几乎可以说人一大的整数均可以存储。
为了区分普通整数和长整数，需要在整数后面加L或者小写l。
练习1：长整型long >>> num2=99999999999999999 >>> type'num2' File "<stdin>", line 1 type'num2' ^ SyntaxError: invalid syntax 注释：说明超出字符限制，使用长整型进行修改。 练习2:长整型long字段（加L或者小写l） >>> num=2L >>> type(num) <type 'long'> >>> num=2l >>> type(num) <type 'long'> >>> num2=9999999999999999999999999999l >>> type(num2) <type 'long'>
浮点型：(不需要声明数据类型)
例如：0.0,12.0， -18.8,3e+7等
1 >>> num=0.0 2 3 >>> type(num) 4 <type 'float'> 5 6 >>> num=12 7 8 >>> type(num) 9 <type 'int'> 10 11 >>> num=12.0 12 13 >>> type(num) 14 <type 'float'> 15
复数型
python对复数提供内嵌支持，这是其他大部分软件所没有的；
复数举列：3.14j，8.32e-36j
1 2 正常的数字赋值类型： 3 >>> c=3.14 4 5 >>> type(c) 6 <type 'float'> 7 8 复数的数字类型： 9 >>> num=3.14j 10 11 >>> type(num) 12 <type 'complex'> 13 14 >>> t1=8.32e-36j 15 16 >>> type(t1) 17 <type 'complex'> 18 19 >>> t1 20 8.3199999999999993e-36j 21 22 >>> num 23 3.1400000000000001j 24 25 >>> print t1 26 8.32e-36j 27 28 >>> print num 29 3.14j 30
整形的其他参数
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 """ 17 def bit_length(self): 18 """ 返回表示该数字的时占用的最少位数 """ 19 """ 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 """ 27 return 0 28 29 def conjugate(self, *args, **kwargs): # real signature unknown 30 """ 返回该复数的共轭复数 """ 31 """ Returns self, the complex conjugate of any int. """ 32 pass 33 34 def __abs__(self): 35 """ 返回绝对值 """ 36 """ x.__abs__() <==> abs(x) """ 37 pass 38 39 def __add__(self, y): 40 """ x.__add__(y) <==> x+y """ 41 pass 42 43 def __and__(self, y): 44 """ x.__and__(y) <==> x&y """ 45 pass 46 47 def __cmp__(self, y): 48 """ 比较两个数大小 """ 49 """ x.__cmp__(y) <==> cmp(x,y) """ 50 pass 51 52 def __coerce__(self, y): 53 """ 强制生成一个元组 """ 54 """ x.__coerce__(y) <==> coerce(x, y) """ 55 pass 56 57 def __divmod__(self, y): 58 """ 相除，得到商和余数组成的元组 """ 59 """ x.__divmod__(y) <==> divmod(x, y) """ 60 pass 61 62 def __div__(self, y): 63 """ x.__div__(y) <==> x/y """ 64 pass 65 66 def __float__(self): 67 """ 转换为浮点类型 """ 68 """ x.__float__() <==> float(x) """ 69 pass 70 71 def __floordiv__(self, y): 72 """ x.__floordiv__(y) <==> x//y """ 73 pass 74 75 def __format__(self, *args, **kwargs): # real signature unknown 76 pass 77 78 def __getattribute__(self, name): 79 """ x.__getattribute__('name') <==> x.name """ 80 pass 81 82 def __getnewargs__(self, *args, **kwargs): # real signature unknown 83 """ 内部调用 __new__方法或创建对象时传入参数使用 """ 84 pass 85 86 def __hash__(self): 87 """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。""" 88 """ x.__hash__() <==> hash(x) """ 89 pass 90 91 def __hex__(self): 92 """ 返回当前数的 十六进制 表示 """ 93 """ x.__hex__() <==> hex(x) """ 94 pass 95 96 def __index__(self): 97 """ 用于切片，数字无意义 """ 98 """ x[y:z] <==> x[y.__index__():z.__index__()] """ 99 pass 100 101 def __init__(self, x, base=10): # known special case of int.__init__ 102 """ 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """ 103 """ 104 int(x=0) -> int or long 105 int(x, base=10) -> int or long 106 107 Convert a number or string to an integer, or return 0 if no arguments 108 are given. If x is floating point, the conversion truncates towards zero. 109 If x is outside the integer range, the function returns a long instead. 110 111 If x is not a number or if base is given, then x must be a string or 112 Unicode object representing an integer literal in the given base. The 113 literal can be preceded by '+' or '-' and be surrounded by whitespace. 114 The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to 115 interpret the base from the string as an integer literal. 116 >>> int('0b100', base=0) 117 # (copied from class doc) 118 """ 119 pass 120 121 def __int__(self): 122 """ 转换为整数 """ 123 """ x.__int__() <==> int(x) """ 124 pass 125 126 def __invert__(self): 127 """ x.__invert__() <==> ~x """ 128 pass 129 130 def __long__(self): 131 """ 转换为长整数 """ 132 """ x.__long__() <==> long(x) """ 133 pass 134 135 def __lshift__(self, y): 136 """ x.__lshift__(y) <==> x<<y """ 137 pass 138 139 def __mod__(self, y): 140 """ x.__mod__(y) <==> x%y """ 141 pass 142 143 def __mul__(self, y): 144 """ x.__mul__(y) <==> x*y """ 145 pass 146 147 def __neg__(self): 148 """ x.__neg__() <==> -x """ 149 pass 150 151 @staticmethod # known case of __new__ 152 def __new__(S, *more): 153 """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ 154 pass 155 156 def __nonzero__(self): 157 """ x.__nonzero__() <==> x != 0 """ 158 pass 159 160 def __oct__(self): 161 """ 返回改值的 八进制 表示 """ 162 """ x.__oct__() <==> oct(x) """ 163 pass 164 165 def __or__(self, y): 166 """ x.__or__(y) <==> x|y """ 167 pass 168 169 def __pos__(self): 170 """ x.__pos__() <==> +x """ 171 pass 172 173 def __pow__(self, y, z=None): 174 """ 幂，次方 """ 175 """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ 176 pass 177 178 def __radd__(self, y): 179 """ x.__radd__(y) <==> y+x """ 180 pass 181 182 def __rand__(self, y): 183 """ x.__rand__(y) <==> y&x """ 184 pass 185 186 def __rdivmod__(self, y): 187 """ x.__rdivmod__(y) <==> divmod(y, x) """ 188 pass 189 190 def __rdiv__(self, y): 191 """ x.__rdiv__(y) <==> y/x """ 192 pass 193 194 def __repr__(self): 195 """转化为解释器可读取的形式 """ 196 """ x.__repr__() <==> repr(x) """ 197 pass 198 199 def __str__(self): 200 """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""" 201 """ x.__str__() <==> str(x) """ 202 pass 203 204 def __rfloordiv__(self, y): 205 """ x.__rfloordiv__(y) <==> y//x """ 206 pass 207 208 def __rlshift__(self, y): 209 """ x.__rlshift__(y) <==> y<<x """ 210 pass 211 212 def __rmod__(self, y): 213 """ x.__rmod__(y) <==> y%x """ 214 pass 215 216 def __rmul__(self, y): 217 """ x.__rmul__(y) <==> y*x """ 218 pass 219 220 def __ror__(self, y): 221 """ x.__ror__(y) <==> y|x """ 222 pass 223 224 def __rpow__(self, x, z=None): 225 """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ 226 pass 227 228 def __rrshift__(self, y): 229 """ x.__rrshift__(y) <==> y>>x """ 230 pass 231 232 def __rshift__(self, y): 233 """ x.__rshift__(y) <==> x>>y """ 234 pass 235 236 def __rsub__(self, y): 237 """ x.__rsub__(y) <==> y-x """ 238 pass 239 240 def __rtruediv__(self, y): 241 """ x.__rtruediv__(y) <==> y/x """ 242 pass 243 244 def __rxor__(self, y): 245 """ x.__rxor__(y) <==> y^x """ 246 pass 247 248 def __sub__(self, y): 249 """ x.__sub__(y) <==> x-y """ 250 pass 251 252 def __truediv__(self, y): 253 """ x.__truediv__(y) <==> x/y """ 254 pass 255 256 def __trunc__(self, *args, **kwargs): 257 """ 返回数值被截取为整形的值，在整形中无意义 """ 258 pass 259 260 def __xor__(self, y): 261 """ x.__xor__(y) <==> x^y """ 262 pass 263 264 denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 265 """ 分母 = 1 """ 266 """the denominator of a rational number in lowest terms""" 267 268 imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 269 """ 虚数，无意义 """ 270 """the imaginary part of a complex number""" 271 272 numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 273 """ 分子 = 数字大小 """ 274 """the numerator of a rational number in lowest terms""" 275 276 real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default 277 """ 实属，无意义 """ 278 """the real part of a complex number"""
