python123数值运算_python基础篇【第二篇】：数据运算、数据类型
一、數據運算
舉個例子一目了然就明白什么是運算符了；例子10+20=30，其中10,20為操作符 ，“+” 稱為運算符。
python支持支持的類型運算符有：算術運算、比較（關系）運算符、賦值運算符、邏輯運算符、位運算符、成員運算符、身份運算符、運算符優先級，下面我們一個個來看。
1、算數運算：
假設變量a=10,變量b=20：
運算符描述實例
+
加 - 兩個對象相加
a + b 輸出結果 30
-
減 - 得到負數或是一個數減去另一個數
a - b 輸出結果 -10
*
乘 - 兩個數相乘或是返回一個被重復若干次的字符串
a * b 輸出結果 200
/
除 - x除以y
b / a 輸出結果 2
%
取模 - 返回除法的余數
b % a 輸出結果 0
**
冪 - 返回x的y次冪
a**b 為10的20次方， 輸出結果 100000000000000000000
//
取整除 - 返回商的整數部分
9//2 輸出結果 4 , 9.0//2.0 輸出結果 4.0
練習實例：
1 #!/usr/bin/env python
2 #-*- coding :utf-8 -*-
3
4 a = 10
5 b = 20
6
7 c = a + b #兩數相加
8 print(c)9
10 c = a - b #兩數相減
11 print(c)12
13 c = a * b #兩數相乘
14 print(c)15
16 c = a / b #兩數相除
17 print(c)18
19 c = a % b #取模,返回除法的余數
20 print(c)21
22 c = a ** b #冪(次方)
23 print(c)24
25 c = a // b #取整數,返回商的整數部分
26 print(c)
以上練習實例執行結果
1 C:\Python\Python35\python.exe E:/Python課程/s13/day2/運算符.py2 30
3 -10
4 200
5 0.5
6 10
7 100000000000000000000
8 09
10 Process finished with exit code 0
2、比較運算符：
運算符描述實例
==
等于 - 比較對象是否相等
(a == b) 返回 False。
!=
不等于 - 比較兩個對象是否不相等
(a != b) 返回 true.
<>
不等于 - 比較兩個對象是否不相等（一般都用!=，在python3中已被移除）
(a <> b) 返回 true。這個運算符類似 != 。
>
大于 - 返回x是否大于y
(a > b) 返回 False。
<
小于 - 返回x是否小于y。所有比較運算符返回1表示真，返回0表示假。這分別與特殊的變量True和False等價。注意，這些變量名的大寫。
(a < b) 返回 true。
>=
大于等于 - 返回x是否大于等于y。
(a >= b) 返回 False。
<=
小于等于 - 返回x是否小于等于y。
(a <= b) 返回 true。
實例練習：
1 a=66
2 b=88
3 c=04
5 a = 10
6 b = 20
78
9 if (a == b): #等于
10 print('a等于b')11 else:12 print('a不等于b')13
14 if (a != b): #不等于
15 print('a不等于b')16 else:17 print('a等于b')18
19 #if (a <> b): #不等于(python2.x)
20 #print('a不等于b')
21 #else:
22 #print('a等于b')
23
24
25 if (a < b): #小于
26 print('a小于b')27 else:28 print('a不小于b')29
30 if (a > b): #大于
31 print('a大于b')32 else:33 print('a不大于b')34
35
36 if (a <= b): #小于等于
37 print('a小于等于b')38 else:39 print('不對')40
41 if (a >= b): #大于等于
42 print('a大于等于b')43 else:44 print('不對')
以上實例執行結果：
C:\Python\Python35\python.exe E:/Python課程/s13/day2/運算符.py
錯誤
a不等于b
錯誤
a小于b
錯誤
a小于等于b
Process finished with exit code 0
3、賦值運算符：
運算符描述實例
=
簡單的賦值運算符
c = a + b 將 a + b 的運算結果賦值為 c
+=
加法賦值運算符
c += a 等效于 c = c + a
-=
減法賦值運算符
c -= a 等效于 c = c - a
*=
乘法賦值運算符
c *= a 等效于 c = c * a
/=
除法賦值運算符
c /= a 等效于 c = c / a
%=
取模賦值運算符
c %= a 等效于 c = c % a
**=
冪賦值運算符
c **= a 等效于 c = c ** a
//=
取整除賦值運算符
c //= a 等效于 c = c // a
實例練習：
1 a = 2
2 b = 3
3 c =04
5 c = a + b #把a+b的變量和賦值給c變量
6 print(c)7
8 c += a #意思是c = c + a
9 print(c)10
11 c -= a #意思是c = c - a
12 print(c)13
14 c *= a #意思是c = c * a
15 print(c)16
17 c /= a #意思是c = c / a
18 print(c)19
20 c %= a #意思是c = c % a
21 print(c)22
23 c **= a #意思是c = c ** a
24 print(c)25
26 c //= a #意思是c = c // a
27 print(c)
以上實例執行結果：
1 C:\Python\Python35\python.exe E:/Python課程/s13/day2/運算符.py2 5
3 7
4 5
5 10
6 5.0
7 1.0
8 1.0
9 0.0
10
11 Process finished with exit code 0
4、位運算符：
執行二進制運算
運算符描述實例
&
按位與運算符：參與運算的兩個值,如果兩個相應位都為1,則該位的結果為1,否則為0
(a & b) 輸出結果 12 ，二進制解釋： 0000 1100
|
按位或運算符：只要對應的二個二進位有一個為1時，結果位就為1。
(a | b) 輸出結果 61 ，二進制解釋： 0011 1101
^
按位異或運算符：當兩對應的二進位相異時，結果為1
(a ^ b) 輸出結果 49 ，二進制解釋： 0011 0001
~
按位取反運算符：對數據的每個二進制位取反,即把1變為0,把0變為1
(~a ) 輸出結果 -61 ，二進制解釋： 1100 0011， 在一個有符號二進制數的補碼形式。
<<
左移動運算符：運算數的各二進位全部左移若干位，由"<<"右邊的數指定移動的位數，高位丟棄，低位補0。
a << 2 輸出結果 240 ，二進制解釋： 1111 0000
>>
右移動運算符：把">>"左邊的運算數的各二進位全部右移若干位，">>"右邊的數指定移動的位數
a >> 2 輸出結果 15 ，二進制解釋： 0000 1111
實例練習：
#!/usr/bin/env python3
a= 10b= 60c=0#一下是數字轉成二進制的方法#例如取10,60數字的二進制#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = 10#0 0 1 1 1 1 0 0 = 60#0 0 0 0 1 0 0 0 = 8#
#所以數字10,60,的二進制分別為#10 = 1010#60 = 111100
c= a & b #按位與運算符:二進制位置中相對應的為1的則為1,否則為0
print(c)#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = a = 10#0 0 1 1 1 1 0 0 = b = 60#0 0 0 0 1 0 0 0 = c = a & b = 8
c= a | b #按位或運算符:只要對應的位置是1的時候就是1
print(c)#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = a = 10#0 0 1 1 1 1 0 0 = b = 60#0 0 1 1 1 1 1 0 = c = a | b = 62
c= a ^ b #按位異或運算符:就是相對應的位置不一樣的時候等于1
print(c)#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = a = 10#0 0 1 1 1 1 0 0 = b = 60#0 0 1 1 0 1 1 0 = c = a ^ b = 54
c= a << 2 #做移動運算符:往左邊移動兩位相當于 10*（2**2）左移n位就是乘以2的n次方
print(c)#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = a = 10#0 0 1 0 1 0 0 0 = c = a << 2 = 40
c= a >> 2 #右移動運算符:往右邊移動兩位
print(c)#128 64 32 16 8 4 2 1#0 0 0 0 1 0 1 0 = a = 10#0 0 0 0 0 0 1 0 = c = a >>2 = 2
以上事例執行結果：
C:\Python\Python35\python.exe E:/Python課程/s13/day2/運算符.py8
62
54
40
2Process finished with exit code 0
5、邏輯運算符：
假設變量 a 為 10, b為 20:
運算符邏輯表達式描述實例
and
x and y
布爾"與" - 如果 x 為 False，x and y 返回 False，否則它返回 y 的計算值。
(a and b) 返回 20
or
x or y
布爾"或" - 如果 x 是 True，它返回 True，否則它返回 y 的計算值。
(a or b) 返回 10
not
not x
布爾"非" - 如果 x 為 True，返回 False 。如果 x 為 False，它返回 True。
not(a and b) 返回 False
6、成員運算符：
運算符描述實例
in
如果在指定的序列中找到值返回 True，否則返回 False。
x 在 y 序列中 , 如果 x 在 y 序列中返回 True。
not in
如果在指定的序列中沒有找到值返回 True，否則返回 False。
x 不在 y 序列中 , 如果 x 不在 y 序列中返回 True。
二、數據類型：
1、數字數據類型
包含四種：
int整型 如：23、333
long長整型：就是比較大比較長的數字
在32位機器上，整數的位數為32位，取值范圍為-2**31～2**31-1，即-2147483648～2147483647
在64位系統上，整數的位數為64位，取值范圍為-2**63～2**63-1，即-9223372036854775808～9223372036854775807
大于以上范圍著都屬于長整型，只不過局限于python2中，在python3中已經不存在了！
float（浮點型）：顧名思義就是帶有小數點的數字，占8個字節（64位），其中52位表示底，11位表示指數，剩下的一位表示符號。
complex（復數）：復數由實數部分和虛數部分組成，一般形式為x＋yj，其中的x是復數的實數部分，y是復數的虛數部分，這里的x和y都是實數。
注：Python中存在小數字池：-5 ～ 257
其中使用的函數：
abs(x)
返回數字的絕對值，如abs(-10) 返回 10
2、布爾值
真或假（Ture、False）
1 或 0
3、字符串（str）
例如："hello world" 這就是字符串，其中字符串有很多種用法如下：
1 classstr(basestring):2 """
3 str(object='') -> string4
5 Return a nice string representation of the object.6 If the argument is a string, the return value is the same object.7 """
8 defcapitalize(self):9 """首字母變大寫"""
10 """
11 S.capitalize() -> string12
13 Return a copy of the string S with only its first character14 capitalized.15 """
16 return ""
17
18 def center(self, width, fillchar=None):19 """內容居中，width：總長度；fillchar：空白處填充內容，默認無"""
20 """
21 S.center(width[, fillchar]) -> string22
23 Return S centered in a string of length width. Padding is24 done using the specified fill character (default is a space)25 """
26 return ""
27
28 def count(self, sub, start=None, end=None):29 """子序列個數"""
30 """
31 S.count(sub[, start[, end]]) -> int32
33 Return the number of non-overlapping occurrences of substring sub in34 string S[start:end]. Optional arguments start and end are interpreted35 as in slice notation.36 """
37 return038
39 def decode(self, encoding=None, errors=None):40 """解碼"""
41 """
42 S.decode([encoding[,errors]]) -> object43
44 Decodes S using the codec registered for encoding. encoding defaults45 to the default encoding. errors may be given to set a different error46 handling scheme. Default is 'strict' meaning that encoding errors raise47 a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'48 as well as any other name registered with codecs.register_error that is49 able to handle UnicodeDecodeErrors.50 """
51 returnobject()52
53 def encode(self, encoding=None, errors=None):54 """編碼，針對unicode"""
55 """
56 S.encode([encoding[,errors]]) -> object57
58 Encodes S using the codec registered for encoding. encoding defaults59 to the default encoding. errors may be given to set a different error60 handling scheme. Default is 'strict' meaning that encoding errors raise61 a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and62 'xmlcharrefreplace' as well as any other name registered with63 codecs.register_error that is able to handle UnicodeEncodeErrors.64 """
65 returnobject()66
67 def endswith(self, suffix, start=None, end=None):68 """是否以 xxx 結束"""
69 """
70 S.endswith(suffix[, start[, end]]) -> bool71
72 Return True if S ends with the specified suffix, False otherwise.73 With optional start, test S beginning at that position.74 With optional end, stop comparing S at that position.75 suffix can also be a tuple of strings to try.76 """
77 returnFalse78
79 def expandtabs(self, tabsize=None):80 """將tab轉換成空格，默認一個tab轉換成8個空格"""
81 """
82 S.expandtabs([tabsize]) -> string83
84 Return a copy of S where all tab characters are expanded using spaces.85 If tabsize is not given, a tab size of 8 characters is assumed.86 """
87 return ""
88
89 def find(self, sub, start=None, end=None):90 """尋找子序列位置，如果沒找到，返回 -1"""
91 """
92 S.find(sub [,start [,end]]) -> int93
94 Return the lowest index in S where substring sub is found,95 such that sub is contained within S[start:end]. Optional96 arguments start and end are interpreted as in slice notation.97
98 Return -1 on failure.99 """
100 return0101
102 def format(*args, **kwargs): #known special case of str.format
103 """字符串格式化，動態參數，將函數式編程時細說"""
104 """
105 S.format(*args, **kwargs) -> string106
107 Return a formatted version of S, using substitutions from args and kwargs.108 The substitutions are identified by braces ('{' and '}').109 """
110 pass
111
112 def index(self, sub, start=None, end=None):113 """子序列位置，如果沒找到，報錯"""
114 S.index(sub [,start [,end]]) ->int115
116 Like S.find() but raise ValueError when the substring is notfound.117 """
118 return 0119
120 def isalnum(self):121 """ 是否是字母和數字 """
122 """
123 S.isalnum() ->bool124
125 Return True if all characters inS are alphanumeric126 and there is at least one character inS, False otherwise.127 """
128 return False129
130 def isalpha(self):131 """ 是否是字母 """
132 """
133 S.isalpha() ->bool134
135 Return True if all characters inS are alphabetic136 and there is at least one character inS, False otherwise.137 """
138 return False139
140 def isdigit(self):141 """ 是否是數字 """
142 """
143 S.isdigit() ->bool144
145 Return True if all characters inS are digits146 and there is at least one character inS, False otherwise.147 """
148 return False149
150 def islower(self):151 """ 是否小寫 """
152 """
153 S.islower() ->bool154
155 Return True if all cased characters in S are lowercase and there is
156 at least one cased character inS, False otherwise.157 """
158 return False159
160 def isspace(self):161 """
162 S.isspace() ->bool163
164 Return True if all characters inS are whitespace165 and there is at least one character inS, False otherwise.166 """
167 return False168
169 def istitle(self):170 """
171 S.istitle() ->bool172
173 Return True if S is a titlecased string and there isat least one174 character inS, i.e. uppercase characters may only follow uncased175 characters andlowercase characters only cased ones. Return False176 otherwise.177 """
178 return False179
180 def isupper(self):181 """
182 S.isupper() ->bool183
184 Return True if all cased characters in S are uppercase and there is
185 at least one cased character inS, False otherwise.186 """
187 return False188
189 def join(self, iterable):190 """ 連接 """
191 """
192 S.join(iterable) ->string193
194 Return a string which is the concatenation of the strings inthe195 iterable. The separator between elements isS.196 """
197 return ""198
199 def ljust(self, width, fillchar=None):200 """ 內容左對齊，右側填充 """
201 """
202 S.ljust(width[, fillchar]) ->string203
204 Return S left-justified in a string of length width. Padding is
205 done using the specified fill character (default isa space).206 """
207 return ""208
209 def lower(self):210 """ 變小寫 """
211 """
212 S.lower() ->string213
214 Return a copy of the string S converted to lowercase.215 """
216 return ""217
218 def lstrip(self, chars=None):219 """ 移除左側空白 """
220 """
221 S.lstrip([chars]) -> string orunicode222
223 Return a copy of the string S with leading whitespace removed.224 If chars is given and not None, remove characters inchars instead.225 If chars isunicode, S will be converted to unicode before stripping226 """
227 return ""228
229 def partition(self, sep):230 """ 分割，前，中，后三部分 """
231 """
232 S.partition(sep) ->(head, sep, tail)233
234 Search for the separator sep in S, and returnthe part before it,235 the separator itself, and the part after it. If the separator is not
236 found, return S andtwo empty strings.237 """
238 pass239
240 def replace(self, old, new, count=None):241 """ 替換 """
242 """
243 S.replace(old, new[, count]) ->string244
245 Return a copy of string S with all occurrences of substring246 old replaced by new. If the optional argument count is
247 given, only the first count occurrences are replaced.248 """
249 return ""250
251 def rfind(self, sub, start=None, end=None):252 """
253 S.rfind(sub [,start [,end]]) ->int254
255 Return the highest index in S where substring sub isfound,256 such that sub iscontained within S[start:end]. Optional257 arguments start and end are interpreted as inslice notation.258
259 Return -1on failure.260 """
261 return 0262
263 def rindex(self, sub, start=None, end=None):264 """
265 S.rindex(sub [,start [,end]]) ->int266
267 Like S.rfind() but raise ValueError when the substring is notfound.268 """
269 return 0270
271 def rjust(self, width, fillchar=None):272 """
273 S.rjust(width[, fillchar]) ->string274
275 Return S right-justified in a string of length width. Padding is
276 done using the specified fill character (default isa space)277 """
278 return ""279
280 def rpartition(self, sep):281 """
282 S.rpartition(sep) ->(head, sep, tail)283
284 Search for the separator sep in S, starting at the end of S, and return
285 the part before it, the separator itself, andthe part after it. If the286 separator is not found, return two empty strings andS.287 """
288 pass289
290 def rsplit(self, sep=None, maxsplit=None):291 """
292 S.rsplit([sep [,maxsplit]]) ->list of strings293
294 Return a list of the words inthe string S, using sep as the295 delimiter string, starting at the end of the string andworking296 to the front. If maxsplit isgiven, at most maxsplit splits are297 done. If sep is not specified or isNone, any whitespace string298 isa separator.299 """
300 return []301
302 def rstrip(self, chars=None):303 """
304 S.rstrip([chars]) -> string orunicode305
306 Return a copy of the string S with trailing whitespace removed.307 If chars is given and not None, remove characters inchars instead.308 If chars isunicode, S will be converted to unicode before stripping309 """
310 return ""311
312 def split(self, sep=None, maxsplit=None):313 """ 分割， maxsplit最多分割幾次 """
314 """
315 S.split([sep [,maxsplit]]) ->list of strings316
317 Return a list of the words inthe string S, using sep as the318 delimiter string. If maxsplit isgiven, at most maxsplit319 splits are done. If sep is not specified or isNone, any320 whitespace string is a separator andempty strings are removed321 fromthe result.322 """
323 return []324
325 def splitlines(self, keepends=False):326 """ 根據換行分割 """
327 """
328 S.splitlines(keepends=False) ->list of strings329
330 Return a list of the lines inS, breaking at line boundaries.331 Line breaks are not included inthe resulting list unless keepends332 is given andtrue.333 """
334 return []335
336 def startswith(self, prefix, start=None, end=None):337 """ 是否起始 """
338 """
339 S.startswith(prefix[, start[, end]]) ->bool340
341 Return True ifS starts with the specified prefix, False otherwise.342 With optional start, test S beginning at that position.343 With optional end, stop comparing S at that position.344 prefix can also be a tuple of strings to try.345 """
346 return False347
348 def strip(self, chars=None):349 """ 移除兩段空白 """
350 """
351 S.strip([chars]) -> string orunicode352
353 Return a copy of the string S with leading andtrailing354 whitespace removed.355 If chars is given and not None, remove characters inchars instead.356 If chars isunicode, S will be converted to unicode before stripping357 """
358 return ""359
360 def swapcase(self):361 """ 大寫變小寫，小寫變大寫 """
362 """
363 S.swapcase() ->string364
365 Return a copy of the string S with uppercase characters366 converted to lowercase andvice versa.367 """
368 return ""369
370 def title(self):371 """
372 S.title() ->string373
374 Return a titlecased version of S, i.e. words start with uppercase375 characters, all remaining cased characters have lowercase.376 """
377 return ""378
379 def translate(self, table, deletechars=None):380 """
381 轉換，需要先做一個對應表，最后一個表示刪除字符集合382 intab = "aeiou"
383 outtab = "12345"
384 trantab =maketrans(intab, outtab)385 str = "this is string example....wow!!!"
386 print str.translate(trantab, 'xm')387 """
388
389 """
390 S.translate(table [,deletechars]) ->string391
392 Return a copy of the string S, where all characters occurring393 in the optional argument deletechars are removed, andthe394 remaining characters have been mapped through the given395 translation table, which must be a string of length 256 orNone.396 If the table argument is None, no translation is applied and
397 the operation simply removes the characters indeletechars.398 """
399 return ""400
401 def upper(self):402 """
403 S.upper() ->string404
405 Return a copy of the string S converted to uppercase.406 """
407 return ""408
409 def zfill(self, width):410 """方法返回指定長度的字符串，原字符串右對齊，前面填充0。"""
411 """
412 S.zfill(width) ->string413
414 Pad a numeric string S with zeros on the left, to fill a field415 of the specified width. The string S isnever truncated.416 """
417 return ""418
419 def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown420 pass421
422 def _formatter_parser(self, *args, **kwargs): # real signature unknown423 pass424
425 def __add__(self, y):426 """ x.__add__(y) <==> x+y """
427 pass428
429 def __contains__(self, y):430 """ x.__contains__(y) <==> y in x """
431 pass432
433 def __eq__(self, y):434 """ x.__eq__(y) <==> x==y """
435 pass436
437 def __format__(self, format_spec):438 """
439 S.__format__(format_spec) ->string440
441 Return a formatted version of S as described by format_spec.442 """
443 return ""444
445 def __getattribute__(self, name):446 """ x.__getattribute__('name') <==> x.name """
447 pass448
449 def __getitem__(self, y):450 """ x.__getitem__(y) <==> x[y] """
451 pass452
453 def __getnewargs__(self, *args, **kwargs): # real signature unknown454 pass455
456 def __getslice__(self, i, j):457 """
458 x.__getslice__(i, j) <==>x[i:j]459
460 Use of negative indices is notsupported.461 """
462 pass463
464 def __ge__(self, y):465 """ x.__ge__(y) <==> x>=y """
466 pass467
468 def __gt__(self, y):469 """ x.__gt__(y) <==> x>y """
470 pass471
472 def __hash__(self):473 """ x.__hash__() <==> hash(x) """
474 pass475
476 def __init__(self, string=''): # known special case of str.__init__477 """
478 str(object='') ->string479
480 Return a nice string representation of the object.481 If the argument is a string, the return value isthe same object.482 #(copied from class doc)
483 """
484 pass485
486 def __len__(self):487 """ x.__len__() <==> len(x) """
488 pass489
490 def __le__(self, y):491 """ x.__le__(y) <==> x<=y """
492 pass493
494 def __lt__(self, y):495 """ x.__lt__(y) <==> x
496 pass497
498 def __mod__(self, y):499 """ x.__mod__(y) <==> x%y """
500 pass501
502 def __mul__(self, n):503 """ x.__mul__(n) <==> x*n """
504 pass505
506 @staticmethod # known case of __new__507 def __new__(S, *more):508 """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
509 pass510
511 def __ne__(self, y):512 """ x.__ne__(y) <==> x!=y """
513 pass514
515 def __repr__(self):516 """ x.__repr__() <==> repr(x) """
517 pass518
519 def __rmod__(self, y):520 """ x.__rmod__(y) <==> y%x """
521 pass522
523 def __rmul__(self, n):524 """ x.__rmul__(n) <==> n*x """
525 pass526
527 def __sizeof__(self):528 """ S.__sizeof__() -> size of S in memory, in bytes """
529 pass530
531 def __str__(self):532 """ x.__str__() <==> str(x) """
533 pass534
535 str536
537 str
str
具體使用特別列出來了幾個:
1 name="tianjie"
2 print(type(name)) #顯示數據是什么類型
3
4 name="tianjie"
5 names=name.__contains__("jie") #字符“jie” 是否在對象中
6
7 name="asdasdasdasdasdasd"
8 names=name.count("as",0,9) #統計在對象0-9索引中“as”字符有幾個
9 print(names)10
11 name="tianjie"
12 names=name.center(20,"*") #寬數20居中，并且兩邊是“*”默認是空
13 print(names)14
15 name="田杰"
16 names=name.encode("gbk") #轉換字符編碼
17 print(names)18
19 name="tianjie"
20 names=name.capitalize() #首字母改為大寫
21 names=name.endswith("ie",0,8) #0-8索引“ie”結尾
22 print(names)23
24 name="tianjie"
25 #names=name.find("j") # #查找“j”在對象中的第一個下標
26 names=name.find("an")27 print(names)
name="tianjieandxiaobai"
names=name.partition("and") #把對象name以“and” 為中心分成三段
print(names)
name="asdfasdfasdfasdfasdsa"
names=name.replace("a","w") #把對象name中的"a"全部替換成"w"
names=name.replace("a","w",3) #把對象name中的“a”前三個替換成“w”
print(names)
萬惡的字符串拼接就是“+”：
python中的字符串在C語言中體現為是一個字符數組，每次創建字符串時候需要在內存中開辟一塊連續的空，并且一旦需要修改字符串的話，就需要再次開辟空間，萬惡的+號每出現一次就會在內從中重新開辟一塊空間。
字符串格式化：
1 name = input("name:")2 age = input("age:")3 job = input("job:")4
5 #print("Infomation of []:" + name + "\nName:[]" + name +"\nAge:[]" + age +"\nJob:[]"+ job )#萬惡的“+” 說的就是這個
6 #print("Infomation of :%s\nName:%s\n\nJob:%s" %(name,name,age,job)) #土鱉寫法格式
7
8 test = '''
9 Infomation of :%s10 Name:%s11 age:%s12 Job:%s13 ''' %(name,name,age,job) #這種寫法格式才是高大上
14 print(test)
4、列表 *
書寫格式如：[1,2,3,"qwe",[123,"q"]],列表里可以包含任何數據，數字、字符、變量、也可以包含列表、字典、元組等。
序列都可以進行的操作包括索引，切片，加，乘，檢查成員，而且是有序的
功能如下：
1 classlist(object):2 """
3 list() -> new empty list4 list(iterable) -> new list initialized from iterable's items5 """
6 def append(self, p_object): #real signature unknown; restored from __doc__
7 """L.append(object) -- append object to end"""
8 pass
9
10 def count(self, value): #real signature unknown; restored from __doc__
11 """L.count(value) -> integer -- return number of occurrences of value"""
12 return013
14 def extend(self, iterable): #real signature unknown; restored from __doc__
15 """L.extend(iterable) -- extend list by appending elements from the iterable"""
16 pass
17
18 def index(self, value, start=None, stop=None): #real signature unknown; restored from __doc__
19 """
20 L.index(value, [start, [stop]]) -> integer -- return first index of value.21 Raises ValueError if the value is not present.22 """
23 return024
25 def insert(self, index, p_object): #real signature unknown; restored from __doc__
26 """L.insert(index, object) -- insert object before index"""
27 pass
28
29 def pop(self, index=None): #real signature unknown; restored from __doc__
30 """
31 L.pop([index]) -> item -- remove and return item at index (default last).32 Raises IndexError if list is empty or index is out of range.33 """
34 pass
35
36 def remove(self, value): #real signature unknown; restored from __doc__
37 """
38 L.remove(value) -- remove first occurrence of value.39 Raises ValueError if the value is not present.40 """
41 pass
42
43 def reverse(self): #real signature unknown; restored from __doc__
44 """L.reverse() -- reverse *IN PLACE*"""
45 pass
46
47 def sort(self, cmp=None, key=None, reverse=False): #real signature unknown; restored from __doc__
48 """
49 L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;50 cmp(x, y) -> -1, 0, 151 """
52 pass
53
54 def __add__(self, y): #real signature unknown; restored from __doc__
55 """x.__add__(y) <==> x+y"""
56 pass
57
58 def __contains__(self, y): #real signature unknown; restored from __doc__
59 """x.__contains__(y) <==> y in x"""
60 pass
61
62 def __delitem__(self, y): #real signature unknown; restored from __doc__
63 """x.__delitem__(y) <==> del x[y]"""
64 pass
65
66 def __delslice__(self, i, j): #real signature unknown; restored from __doc__
67 """
68 x.__delslice__(i, j) <==> del x[i:j]69
70 Use of negative indices is not supported.71 """
72 pass
73
74 def __eq__(self, y): #real signature unknown; restored from __doc__
75 """x.__eq__(y) <==> x==y"""
76 pass
77
78 def __getattribute__(self, name): #real signature unknown; restored from __doc__
79 """x.__getattribute__('name') <==> x.name"""
80 pass
81
82 def __getitem__(self, y): #real signature unknown; restored from __doc__
83 """x.__getitem__(y) <==> x[y]"""
84 pass
85
86 def __getslice__(self, i, j): #real signature unknown; restored from __doc__
87 """
88 x.__getslice__(i, j) <==> x[i:j]89
90 Use of negative indices is not supported.91 """
92 pass
93
94 def __ge__(self, y): #real signature unknown; restored from __doc__
95 """x.__ge__(y) <==> x>=y"""
96 pass
97
98 def __gt__(self, y): #real signature unknown; restored from __doc__
99 """x.__gt__(y) <==> x>y"""
100 pass
101
102 def __iadd__(self, y): #real signature unknown; restored from __doc__
103 """x.__iadd__(y) <==> x+=y"""
104 pass
105
106 def __imul__(self, y): #real signature unknown; restored from __doc__
107 """x.__imul__(y) <==> x*=y"""
108 pass
109
110 def __init__(self, seq=()): #known special case of list.__init__
111 """
112 list() -> new empty list113 list(iterable) -> new list initialized from iterable's items114 # (copied from class doc)115 """
116 pass
117
118 def __iter__(self): #real signature unknown; restored from __doc__
119 """x.__iter__() <==> iter(x)"""
120 pass
121
122 def __len__(self): #real signature unknown; restored from __doc__
123 """x.__len__() <==> len(x)"""
124 pass
125
126 def __le__(self, y): #real signature unknown; restored from __doc__
127 """x.__le__(y) <==> x<=y"""
128 pass
129
130 def __lt__(self, y): #real signature unknown; restored from __doc__
131 """x.__lt__(y) <==> x
132 pass
133
134 def __mul__(self, n): #real signature unknown; restored from __doc__
135 """x.__mul__(n) <==> x*n"""
136 pass
137
138 @staticmethod #known case of __new__
139 def __new__(S, *more): #real signature unknown; restored from __doc__
140 """T.__new__(S, ...) -> a new object with type S, a subtype of T"""
141 pass
142
143 def __ne__(self, y): #real signature unknown; restored from __doc__
144 """x.__ne__(y) <==> x!=y"""
145 pass
146
147 def __repr__(self): #real signature unknown; restored from __doc__
148 """x.__repr__() <==> repr(x)"""
149 pass
150
151 def __reversed__(self): #real signature unknown; restored from __doc__
152 """L.__reversed__() -- return a reverse iterator over the list"""
153 pass
154
155 def __rmul__(self, n): #real signature unknown; restored from __doc__
156 """x.__rmul__(n) <==> n*x"""
157 pass
158
159 def __setitem__(self, i, y): #real signature unknown; restored from __doc__
160 """x.__setitem__(i, y) <==> x[i]=y"""
161 pass
162
163 def __setslice__(self, i, j, y): #real signature unknown; restored from __doc__
164 """
165 x.__setslice__(i, j, y) <==> x[i:j]=y166
167 Use of negative indices is not supported.168 """
169 pass
170
171 def __sizeof__(self): #real signature unknown; restored from __doc__
172 """L.__sizeof__() -- size of L in memory, in bytes"""
173 pass
174
175 __hash__ =None176
177 list
list
具體用法：
1 name=[1,2,3]2 name.extend(["g","k",]) #合并，也可以合并一個列表
3
4 k=name.pop(0) #取出指定索引的元素，默認是最后一個元素，把取出來的元素在重新賦值
5 print(k)6
7 name=[1,2,3,"q","a"]8 name.reverse() #翻轉，順序顛倒
9
10 name.append("tianjie") #追加，在末尾添加
11
12 name.remove("a") #指定刪除哪個元素
13
14 name.insert(3,"xiaobai") #在指定下標后添加
15
16 name.index("q") #取出指定下標
17
18 name.count("a") #統計a在列表name中出現的次數
19
20 namel.sort() #排序，但是字符轉不能與數字在一起排序
21
22 name.clear() #清空列表
23
24 name.copy() #復制，這里的復制指的是淺復制
實例1練習：
1 創建個列表2 name=["潘文斌","田杰","榪棟勝","潘東林","牛恒博","杜保強","梁連","趙鴻飛"]3
4 #新添加元素
5 name.insert(4,"張三")6 name.insert(5,"李四")7
8 #取出第3-8之間的人
9 print(name[2:8])10
11 #一次刪除新添的兩個名字
12 for i in name[4:6]:13 name.remove(i)14 print(name)15 #或者del name[4:6]
16
17 #刪除第7個人
18 name.pop(7)19
20 #更改元素
21 name[0]="潘文斌組長"
22 #隔一個人打印一個人
23 print(name[::2])
View Code
練習2：
創建列表如：
name=[6,6,4,564,5,6,56,45,6,45,64,56,45,6,655,5,56,2,2,2,34,2,34,6,6,4,4,4,4,5,5]1、把列表中數字6全部換成66662、把列表中數字4全部刪掉
1 name=[6,6,4,564,5,6,56,45,6,45,64,56,45,6,655,5,56,2,2,2,34,2,34,6,6,4,4,4,4,5,5]2 count=name.count(6)3
4 for i in range(name.count(6)):5 nums=name.index(6)6 name[nums]=6666
7
8 for i in range(name.count(4)):9 nums1=name.index(4)10 name.pop(nums1)11
12 print(name)
View Code
練習3：
練習：元素分類
有如下值集合 [11,22,33,44,55,66,77,88,99,90...]，將所有大于 66 的值保存至字典的第一個key中，將小于 66的值保存至第二個key的值中。
即： {'k1': 大于66 , 'k2': 小于66}
1 li=[11,22,33,44,55,66,77,88,99]2 dic={}3 a=[]4 b=[]5 for i inli:6 if i>66:7 a.append(i)8 else:9 b.append(1)10 dic["k1"]=a11 dic["k2"]=b12 print(dic)
View Code
5、元組
我的理解就是，不能修改，添加，刪除的列表
書寫格式:("qwe","asd",1,2,3,4)
功能如下：
1 classtuple(object):2 """
3 tuple() -> empty tuple4 tuple(iterable) -> tuple initialized from iterable's items5
6 If the argument is a tuple, the return value is the same object.7 """
8 def count(self, value): #real signature unknown; restored from __doc__
9 """T.count(value) -> integer -- return number of occurrences of value"""
10 return011
12 def index(self, value, start=None, stop=None): #real signature unknown; restored from __doc__
13 """
14 T.index(value, [start, [stop]]) -> integer -- return first index of value.15 Raises ValueError if the value is not present.16 """
17 return018
19 def __add__(self, y): #real signature unknown; restored from __doc__
20 """x.__add__(y) <==> x+y"""
21 pass
22
23 def __contains__(self, y): #real signature unknown; restored from __doc__
24 """x.__contains__(y) <==> y in x"""
25 pass
26
27 def __eq__(self, y): #real signature unknown; restored from __doc__
28 """x.__eq__(y) <==> x==y"""
29 pass
30
31 def __getattribute__(self, name): #real signature unknown; restored from __doc__
32 """x.__getattribute__('name') <==> x.name"""
33 pass
34
35 def __getitem__(self, y): #real signature unknown; restored from __doc__
36 """x.__getitem__(y) <==> x[y]"""
37 pass
38
39 def __getnewargs__(self, *args, **kwargs): #real signature unknown
40 pass
41
42 def __getslice__(self, i, j): #real signature unknown; restored from __doc__
43 """
44 x.__getslice__(i, j) <==> x[i:j]45
46 Use of negative indices is not supported.47 """
48 pass
49
50 def __ge__(self, y): #real signature unknown; restored from __doc__
51 """x.__ge__(y) <==> x>=y"""
52 pass
53
54 def __gt__(self, y): #real signature unknown; restored from __doc__
55 """x.__gt__(y) <==> x>y"""
56 pass
57
58 def __hash__(self): #real signature unknown; restored from __doc__
59 """x.__hash__() <==> hash(x)"""
60 pass
61
62 def __init__(self, seq=()): #known special case of tuple.__init__
63 """
64 tuple() -> empty tuple65 tuple(iterable) -> tuple initialized from iterable's items66
67 If the argument is a tuple, the return value is the same object.68 # (copied from class doc)69 """
70 pass
71
72 def __iter__(self): #real signature unknown; restored from __doc__
73 """x.__iter__() <==> iter(x)"""
74 pass
75
76 def __len__(self): #real signature unknown; restored from __doc__
77 """x.__len__() <==> len(x)"""
78 pass
79
80 def __le__(self, y): #real signature unknown; restored from __doc__
81 """x.__le__(y) <==> x<=y"""
82 pass
83
84 def __lt__(self, y): #real signature unknown; restored from __doc__
85 """x.__lt__(y) <==> x
86 pass
87
88 def __mul__(self, n): #real signature unknown; restored from __doc__
89 """x.__mul__(n) <==> x*n"""
90 pass
91
92 @staticmethod #known case of __new__
93 def __new__(S, *more): #real signature unknown; restored from __doc__
94 """T.__new__(S, ...) -> a new object with type S, a subtype of T"""
95 pass
96
97 def __ne__(self, y): #real signature unknown; restored from __doc__
98 """x.__ne__(y) <==> x!=y"""
99 pass
100
101 def __repr__(self): #real signature unknown; restored from __doc__
102 """x.__repr__() <==> repr(x)"""
103 pass
104
105 def __rmul__(self, n): #real signature unknown; restored from __doc__
106 """x.__rmul__(n) <==> n*x"""
107 pass
108
109 def __sizeof__(self): #real signature unknown; restored from __doc__
110 """T.__sizeof__() -- size of T in memory, in bytes"""
111 pass
112
113 tuple
tuple
常用的工就兩個：
1 name=(1,2,3,4,"q","e","c")2 name.index("q") #查看下標
3 name.count("e") #統計
6、字典
字典的每個鍵值(key=>value)對用冒號(:)分割，每個對之間用逗號(,)分割，整個字典包括在花括號({})中，格式如下：
{"name":"tianjie","age":18}
{"host":'192.168.1.2',"port":80}
注：循環時默認循環key
功能如下：
1 classdict(object):2 """
3 dict() -> new empty dictionary4 dict(mapping) -> new dictionary initialized from a mapping object's5 (key, value) pairs6 dict(iterable) -> new dictionary initialized as if via:7 d = {}8 for k, v in iterable:9 d[k] = v10 dict(**kwargs) -> new dictionary initialized with the name=value pairs11 in the keyword argument list. For example: dict(one=1, two=2)12 """
13
14 def clear(self): #real signature unknown; restored from __doc__
15 """清除內容"""
16 """D.clear() -> None. Remove all items from D."""
17 pass
18
19 def copy(self): #real signature unknown; restored from __doc__
20 """淺拷貝"""
21 """D.copy() -> a shallow copy of D"""
22 pass
23
24 @staticmethod #known case
25 def fromkeys(S, v=None): #real signature unknown; restored from __doc__
26 """
27 dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.28 v defaults to None.29 """
30 pass
31
32 def get(self, k, d=None): #real signature unknown; restored from __doc__
33 """根據key獲取值，d是默認值"""
34 """D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None."""
35 pass
36
37 def has_key(self, k): #real signature unknown; restored from __doc__
38 """是否有key python3中移除"""
39 """D.has_key(k) -> True if D has a key k, else False"""
40 returnFalse41
42 def items(self): #real signature unknown; restored from __doc__
43 """所有項的列表形式"""
44 """D.items() -> list of D's (key, value) pairs, as 2-tuples"""
45 return[]46
47 def iteritems(self): #real signature unknown; restored from __doc__
48 """項可迭代"""
49 """D.iteritems() -> an iterator over the (key, value) items of D"""
50 pass
51
52 def iterkeys(self): #real signature unknown; restored from __doc__
53 """key可迭代"""
54 """D.iterkeys() -> an iterator over the keys of D"""
55 pass
56
57 def itervalues(self): #real signature unknown; restored from __doc__
58 """value可迭代"""
59 """D.itervalues() -> an iterator over the values of D"""
60 pass
61
62 def keys(self): #real signature unknown; restored from __doc__
63 """所有的key列表"""
64 """D.keys() -> list of D's keys"""
65 return[]66
67 def pop(self, k, d=None): #real signature unknown; restored from __doc__
68 """獲取并在字典中移除"""
69 """
70 D.pop(k[,d]) -> v, remove specified key and return the corresponding value.71 If key is not found, d is returned if given, otherwise KeyError is raised72 """
73 pass
74
75 def popitem(self): #real signature unknown; restored from __doc__
76 """獲取并在字典中移除"""
77 """
78 D.popitem() -> (k, v), remove and return some (key, value) pair as a79 2-tuple; but raise KeyError if D is empty.80 """
81 pass
82
83 def setdefault(self, k, d=None): #real signature unknown; restored from __doc__
84 """如果key不存在，則創建，如果存在，則返回已存在的值且不修改"""
85 """D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D"""
86 pass
87
88 def update(self, E=None, **F): #known special case of dict.update
89 """更新90 {'name':'alex', 'age': 18000}91 [('name','sbsbsb'),]92 """
93 """
94 D.update([E, ]**F) -> None. Update D from dict/iterable E and F.95 If E present and has a .keys() method, does: for k in E: D[k] = E[k]96 If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v97 In either case, this is followed by: for k in F: D[k] = F[k]98 """
99 pass
100
101 def values(self): #real signature unknown; restored from __doc__
102 """所有的值"""
103 """D.values() -> list of D's values"""
104 return[]105
106 def viewitems(self): #real signature unknown; restored from __doc__
107 """所有項，只是將內容保存至view對象中"""
108 """D.viewitems() -> a set-like object providing a view on D's items"""
109 pass
110
111 def viewkeys(self): #real signature unknown; restored from __doc__
112 """D.viewkeys() -> a set-like object providing a view on D's keys"""
113 pass
114
115 def viewvalues(self): #real signature unknown; restored from __doc__
116 """D.viewvalues() -> an object providing a view on D's values"""
117 pass
118
119 def __cmp__(self, y): #real signature unknown; restored from __doc__
120 """x.__cmp__(y) <==> cmp(x,y)"""
121 pass
122
123 def __contains__(self, k): #real signature unknown; restored from __doc__
124 """D.__contains__(k) -> True if D has a key k, else False"""
125 returnFalse126
127 def __delitem__(self, y): #real signature unknown; restored from __doc__
128 """x.__delitem__(y) <==> del x[y]"""
129 pass
130
131 def __eq__(self, y): #real signature unknown; restored from __doc__
132 """x.__eq__(y) <==> x==y"""
133 pass
134
135 def __getattribute__(self, name): #real signature unknown; restored from __doc__
136 """x.__getattribute__('name') <==> x.name"""
137 pass
138
139 def __getitem__(self, y): #real signature unknown; restored from __doc__
140 """x.__getitem__(y) <==> x[y]"""
141 pass
142
143 def __ge__(self, y): #real signature unknown; restored from __doc__
144 """x.__ge__(y) <==> x>=y"""
145 pass
146
147 def __gt__(self, y): #real signature unknown; restored from __doc__
148 """x.__gt__(y) <==> x>y"""
149 pass
150
151 def __init__(self, seq=None, **kwargs): #known special case of dict.__init__
152 """
153 dict() -> new empty dictionary154 dict(mapping) -> new dictionary initialized from a mapping object's155 (key, value) pairs156 dict(iterable) -> new dictionary initialized as if via:157 d = {}158 for k, v in iterable:159 d[k] = v160 dict(**kwargs) -> new dictionary initialized with the name=value pairs161 in the keyword argument list. For example: dict(one=1, two=2)162 # (copied from class doc)163 """
164 pass
165
166 def __iter__(self): #real signature unknown; restored from __doc__
167 """x.__iter__() <==> iter(x)"""
168 pass
169
170 def __len__(self): #real signature unknown; restored from __doc__
171 """x.__len__() <==> len(x)"""
172 pass
173
174 def __le__(self, y): #real signature unknown; restored from __doc__
175 """x.__le__(y) <==> x<=y"""
176 pass
177
178 def __lt__(self, y): #real signature unknown; restored from __doc__
179 """x.__lt__(y) <==> x
180 pass
181
182 @staticmethod #known case of __new__
183 def __new__(S, *more): #real signature unknown; restored from __doc__
184 """T.__new__(S, ...) -> a new object with type S, a subtype of T"""
185 pass
186
187 def __ne__(self, y): #real signature unknown; restored from __doc__
188 """x.__ne__(y) <==> x!=y"""
189 pass
190
191 def __repr__(self): #real signature unknown; restored from __doc__
192 """x.__repr__() <==> repr(x)"""
193 pass
194
195 def __setitem__(self, i, y): #real signature unknown; restored from __doc__
196 """x.__setitem__(i, y) <==> x[i]=y"""
197 pass
198
199 def __sizeof__(self): #real signature unknown; restored from __doc__
200 """D.__sizeof__() -> size of D in memory, in bytes"""
201 pass
202
203 __hash__ =None204
205 dict
dict
具體用法：
id_db={123:{"name":"tianjie","age":12,"job":"IT",
},345:{"name":"xiaobai","age":13,"job":"IT",
},
}#id_db[123]["name"]="xiaohei" #修改#print(id_db)
#id_db[345]["xingbie"]="nan" #添加#print(id_db)
#id_db[123].pop("age") #刪除## del id_db[123]["name"]## print(id_db)
##d=id_db.get(123) #取值 沒有值，也不報錯#d=id_db.get(456)#print(d)
#dic2={#"name":"xiaoma",#"age":18,#"job":"IT",#}#id_db.update(dic2) #覆蓋，有就覆蓋，不存在添加新的#print(id_db)
#print(id_db.keys()) #取key#print(id_db.values())#取元素
print(dict.fromkeys([1,2,3,4],'ddd'))#把后面的ddd做元素分別賦值給前面的列表生成字典（據說里面有坑）
dic1 = {
'alex':'good',
'wuSIR':'good',
'wb':'DSB'
}
for i in dic1:
print(i)
#循環取得是key
#輸出結果為：
alex
wuSIR
wb
print(len(dic1)) #計算字典元素個數，即鍵的總數
print(str(dic1)) #輸出字典以可打印的字符串表示
print(type(dic1)) #返回輸入的變量類型，如果變量是字典就返回字典類型
練習：
練習：元素分類
有如下值集合 [11,22,33,44,55,66,77,88,99,90...]，將所有大于 66 的值保存至字典的第一個key中，將小于 66的值保存至第二個key的值中。
即： {'k1': 大于66 , 'k2': 小于66}
1 li=[11,22,33,44,55,66,77,88,99]2 dic={}3 for i inli:4 if i>66:5 if "k1" indic.keys():6 dic["k1"].append(i)7 else:8 dic["k1"]=[i,]9 else:10 if "k2" indic.keys():11 dic["k2"].append(i)12 else:13 dic["k2"] =[i,]14 print(dic)
View Code
1 num=[11,22,33,44,55,66,77,88,99]2 name=collections.defaultdict(list) #指定了默認字典
3 for i innum:4 if i >66:5 name["k1"].append(i)6 else:7 name["k2"].append(i)8 print(name)
View Code
7、set集合：
首先說set的是什么？
set是一個無序的，不可重復的元組集合，也可嵌套。
創建集合：
se={1,2,3,4}
se=set(1,2,3,4)
se=set([1,2,3,4,"q","a"])
集合都有哪些功能：
1 classset(object):2 """
3 set() -> new empty set object4 set(iterable) -> new set object5
6 Build an unordered collection of unique elements.7 """
8 def add(self, *args, **kwargs): #real signature unknown
9 """
10 Add an element to a set，添加元素11
12 This has no effect if the element is already present.13 """
14 pass
15
16 def clear(self, *args, **kwargs): #real signature unknown
17 """Remove all elements from this set. 清除內容"""
18 pass
19
20 def copy(self, *args, **kwargs): #real signature unknown
21 """Return a shallow copy of a set. 淺拷貝"""
22 pass
23
24 def difference(self, *args, **kwargs): #real signature unknown
25 """
26 Return the difference of two or more sets as a new set. A中存在，B中不存在27
28 (i.e. all elements that are in this set but not the others.)29 """
30 pass
31
32 def difference_update(self, *args, **kwargs): #real signature unknown
33 """Remove all elements of another set from this set. 從當前集合中刪除和B中相同的元素"""
34 pass
35
36 def discard(self, *args, **kwargs): #real signature unknown
37 """
38 Remove an element from a set if it is a member.39
40 If the element is not a member, do nothing. 移除指定元素，不存在不保錯41 """
42 pass
43
44 def intersection(self, *args, **kwargs): #real signature unknown
45 """
46 Return the intersection of two sets as a new set. 交集47
48 (i.e. all elements that are in both sets.)49 """
50 pass
51
52 def intersection_update(self, *args, **kwargs): #real signature unknown
53 """Update a set with the intersection of itself and another. 取交集并更更新到A中"""
54 pass
55
56 def isdisjoint(self, *args, **kwargs): #real signature unknown
57 """Return True if two sets have a null intersection. 如果沒有交集，返回True，否則返回False"""
58 pass
59
60 def issubset(self, *args, **kwargs): #real signature unknown
61 """Report whether another set contains this set. 是否是子序列"""
62 pass
63
64 def issuperset(self, *args, **kwargs): #real signature unknown
65 """Report whether this set contains another set. 是否是父序列"""
66 pass
67
68 def pop(self, *args, **kwargs): #real signature unknown
69 """
70 Remove and return an arbitrary set element.71 Raises KeyError if the set is empty. 移除元素72 """
73 pass
74
75 def remove(self, *args, **kwargs): #real signature unknown
76 """
77 Remove an element from a set; it must be a member.78
79 If the element is not a member, raise a KeyError. 移除指定元素，不存在保錯80 """
81 pass
82
83 def symmetric_difference(self, *args, **kwargs): #real signature unknown
84 """
85 Return the symmetric difference of two sets as a new set. 對稱差集86
87 (i.e. all elements that are in exactly one of the sets.)88 """
89 pass
90
91 def symmetric_difference_update(self, *args, **kwargs): #real signature unknown
92 """Update a set with the symmetric difference of itself and another. 對稱差集，并更新到a中"""
93 pass
94
95 def union(self, *args, **kwargs): #real signature unknown
96 """
97 Return the union of sets as a new set. 并集98
99 (i.e. all elements that are in either set.)100 """
101 pass
102
103 def update(self, *args, **kwargs): #real signature unknown
104 """Update a set with the union of itself and others. 更新"""
105 pass
set
具體用法：
1 name=set() #定義集合
2 name.add("tianjie") #添加集合
3 print(name)4 name.update(["k1","a1","a2","a3"])#更新
5 print(name)6
7 name1=set(["k2","k3","k4","a1"])8 print(name1)9 name2=name1.difference(name) #取變量name1中，name變量中不存在的元素生成一個新的set
10 print(name2)11
12 name3=set(["v1","v2","v3","v4"])13 print(name3)14
15 name4=name3.intersection(["v1","d1","v0","v2"])#取交集生成新的set or name4=name3.intersection(name1) 里面也可以是另一個集合變量
16 print(name4)17
18 name3.intersection_update(name4)#取交集修改原來的set 就是把原來name3替換成交集的結果
19 print(name3)20
21 print(name3.isdisjoint(name4)) #如果name3和name4是否有交集 沒有則返回True 有就返回False
22 print(name3.issuperset(name4))#是name3是否是name4父集,是就為True ，就是name3是否包含name4
23 name4=name3.pop() #移除一個元素，獲取到移除的元素,注意這是隨機的
24 print(name3)25 print(name4)26
27 name3.remove("v2") #移除指定元素，沒有就報錯
28 print(name3)29
30 name3.discard("v2") #移除指定元素，沒有也不報錯
實例練習：
尋找差異：
#數據庫中原有
old_dict ={"#1":{ 'hostname':c1, 'cpu_count': 2, 'mem_capicity': 80},"#2":{ 'hostname':c1, 'cpu_count': 2, 'mem_capicity': 80}"#3":{ 'hostname':c1, 'cpu_count': 2, 'mem_capicity': 80}
}#cmdb 新匯報的數據
new_dict ={"#1":{ 'hostname':c1, 'cpu_count': 2, 'mem_capicity': 800},"#3":{ 'hostname':c1, 'cpu_count': 2, 'mem_capicity': 80}"#4":{ 'hostname':c2, 'cpu_count': 2, 'mem_capicity': 80}
}
列出需要刪除，需要添加，需要更新的項，
無需考慮內部元素是否改變，只要原來存在，新匯報也存在，就是需要更新
1 需要添加的項：2 就是新的有（new_dict）,舊的沒有的項（old_dict）添加3 代碼：4 A=set(old_dict)5 B=set(new_dict)6 s1=B.difference(A)7 需要刪除的項：8 就是舊的有，新的沒有 刪除9 代碼：10 s2=A.difference(B)11 需要更新的項：12 就是舊的有，新的也有 就是需要更新的13 s3=A.intersection(B)
集合簡寫（特殊字符代替）：
1 name1=set(["v1","v2","v3","v4"])2 print(name1)3 name2=set(["v1","v2","a","a1","v6"])4 print(name2)5 print(name1&name2) #交集
6 print(name1|name2) #并集
7 print(name1-name2)#差集顯示name1差集，name1有name2沒有
8 print(name2-name1)#差集顯示name2差集，name2有name1沒有
9 print(name1^name2)#求對稱差集，name1沒有name2的，name2中的沒有name1的
以上輸出結果：
1 C:\Python\Python35\python.exe D:/學習功課/s13/day3/set集合.py2 {'v1', 'v2', 'v4', 'v3'}3 {'a1', 'v1', 'a', 'v2', 'v6'}4 {'v1', 'v2'}5 {'v4', 'v2', 'v6', 'a1', 'v1', 'v3', 'a'}6 {'v4', 'v3'}7 {'a1', 'a', 'v6'}8 {'v4', 'v6', 'a1', 'v3', 'a'}9
10 Process finished with exit code 0
總結
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