1, a digital type int
- int (string converted to digital)
a = "123" print(type(a),a) b = int(a) print(type(b),b) num = "0011" v = int(num,base=16) print(v)
PS: type print data type, base = 16 is to print out the decimal num results in hexadecimal.
- bit_lenght (the current number of binary digits)
age = 5 r = age.bit_length() print(r)
PS: 5 to 101 binary number (three digits), so the print result of three.
2, the type of string str
- capitalize (first letter capitalized)
test = "alex" v = test.capitalize() print(v)
PS: Output Alex.
- Lower and casefold and islower (the first two letters will change all lowercase, casefold more advanced, a lot can change lowercase unknown special symbols, the last to determine whether lowercase)
test = "aLex" v1 = test.casefold() print(v1) v2 = test.lower() print(v2)
test = "aLex" v = test.islower() print(v)
PS: Alex first stage output, the output of the second segment False, Upper and issupper supra, the string of uppercase and determines whether the string to uppercase.
- Center and ljust and the rjust (width are provided, and then the contents centered, left aligned, right aligned)
test = "aLex" v = test.center(20,"*") print(v)
test = "aLex" v = test.ljust(20,"*") print(v)
test = "aLex" v = test.rjust(20,"*") print(v)
PS: outputs ******** aLex ********, aLex ****************, ********** ****** aLex, 20 refers to the generation of the total length of the set, "*" is filled with content and only one character (available in Chinese), the default do not fill the space.
- COUNT (look for sequences in a string of occurrences)
test = "aLexalexr" v1 = test.count('ex') print(v1) v2 = test.count('ex',5,6) print(v2)
PS: indicates the number of lookups ex appear in the string, represents 5,6 Look defined between the fifth to the sixth character, v1 output 2, v2 0 output.
- endsWith and startsWith (ending what character and start what character)
test = "aLex" v1 = test.endswith('ex') print(v1) v2 = test.startswith('ex') print(v2)
PS: v1 is True, v2 is Flase, 'ex' can be added later in determining which parameter indicates the interval.
- the Find and index (from front to back string substring find the location of the first occurrence)
test="alexalex" v1 = test.find('ex') print(v1) v2 = test.find('ex',5,8) print(v2)
PS: v1 output 2, v2 represents the look in [5,8) interval, if no results are returned to find -1, index usage above, but find no error will result, recommended find.
- the format (format, the string is replaced with a placeholder value specified)
test = 'i am {name},age{a}' print(test) v = test.format(name='alex',a=19) print(v)
test = 'i am {0},age{1}' print(test) v = test.format('alex',19) print(v)
PS: output as two pieces of code, can replace the contents described in numerical order.
- isalnum and the isalpha (former determines whether string contains only letters and numbers, which determines whether the letters and characters)
test = "uasf_+" v = test.isalnum() print(v)
test="as2df" v = test.isalpha() print(v)
PS: the first stage output False, if the output is removed _ + True; second stage output False, if removed two output True.
- expandtabs (according to the number of characters for a string punctuation)
test="usebcsdy\tsdvdve" v = test.expandtabs(6) print(v)
PS: every six punctuation characters, when faced \ t automatically cut off and the number of characters occupy the rest of the print results usebcs dy \ t sdvdve.
- isdecimal and isdigit and IsNumeric (determines whether the input is a number, the first common, because it can be used to calculate the second number can also identify a special third number can be recognized on the Chinese)
test="②" v1 = test.isdecimal() v2 = test.isdigit() print(v1,v2)
test="二" v1 = test.isdecimal() v2 = test.isdigit() v3 = test.isnumeric() print(v1,v2,v3)
PS: the first stage output v1 False, v2 output True; second segment v1, v2 output False, v3 output True.
- isIdentifier (used to determine whether the legal variable name)
a = "def" v = a.isidentifier() print(v)
PS: Output True, isidentifier judgment rule only letters, numbers and underscores.
- isPrintable (whether there is a character not displayed)
test = "oiuas\tdfkj" v = test.isprintable() print(v)
PS: \ t After printing is not displayed, the output False, remove \ t output is True.
- isspace (to determine whether all spaces)
test = "" v = test.isspace() print(v)
PS: empty string output False, when all spaces output True.
- title and istitle (former converted to capitalize the first letter of each word in the title format, which determines whether the title format)
test = "Return True if all cased characters in S are uppercase and there is" v1 = test.title() print(v1) v2 = test.istitle() print(v2)
PS: v1 all the words capitalized, v2 output False.
- the Join (string elements in each of the specified delimiter splicing)
= Test " girlfriend fangfang " V = " " .join (Test) Print (V)
PS: Output "girlfriend Fang Fang", the space can also be spliced to replace other symbols.
- Strip and lstrip and The rstrip (Removes the specified string from both sides, left, right and most preferentially matching substring, the default remove spaces, \ t, \ n)
test = " alex " v1 = test.strip() v2 = test.lstrip() v3 = test.rstrip() print(v1,v2,v3)
test = "alexxa" v = test.rstrip('xa') print(v)
PS: the first stage output alex, alex (blank), (blank) alex, the output of the second paragraph of ale.
- maketrans and Translate (corresponding to create characters and replace)
v = "liuguifangxiaobaobei" m = str.maketrans("aeiou","12345") new_v = v.translate(m) print(new_v)
PS: the string is replaced with 12345 aeiou output l35g53f1ngx314b14b23.
- Partition and rpartition , Split and rsplit (two front left and right divided according to a given character string comprising characters divided into three parts, the divided two split does not include multi-character)
test = "testasdsddfg" v1 = test.partition('s') v2 = test.split('s') print(v1,v2)
PS: v1 output [ 'te', 's',' tasdsddfg '], rpartition from the right side of the first divided s, v2 output [' te ',' ta ',' d ',' ddfg '],' s' after division can also add several parameters s, rsplit the right division.
- splitlines (can only be divided according to a newline)
test = "liu\ngui\nfang\n" v = test.splitlines(False) print(v)
PS: output [ 'liu', 'gui', 'fang'], True and False parameters decide whether to keep line breaks.
- swapcase (all character case conversion)
test = "aLex" v = test.swapcase() print(v)
PS: output AlEX.
- Replace (substring in the replacement string)
test = "liuguifangu" v = test.replace("gu",'bbb') print(v)
PS: Output "liubbbifangu", the 'bbb' number of parameter settings can also add the string to be replaced.
3, list the type of list
- the append (be appended to the original list)
li = [11,22,33,44] li.append(5) li.append("alex") li.append([1234,2314]) print(li)
PS: output [11,22,33,44, 'alex', [1234,2314]].
- the Clear (Clear List)
li = [11,22,33,44 ] li.clear () print (li)
PS: output [], an empty string.
- Copy (Copy String)
= li [11,22,33,44 ] v = li.copy () print (v)
PS: This is a shallow copy copy.
- COUNT (count the number of elements appear)
= li [11,22,33,22,44 ] v = li.count (22 ) print (v)
PS: Output 2.
- Extend (extended original list)
= Li [11,22,33,44 ] li.extend ([ 9898, " Liugui Fang " ]) li.extend ( " Liugui Fang " ) Print (Li)
PS: output [11,22,33,44,9898 'Liugui Fang', 'Liu', 'you', 'aryl'], is an iterative Extend the object, i.e. extended by character, to the append will append a whole to the back.
- index (the index value acquisition position)
= li [11,22,33,22,44 ] v = li.index (22 ) print (v)
PS: left start index, to a given value when the index index is stopped, the output 1.
- INSERT (insert elements at the specified index)
= [11,22,33,44 ] li.insert (0, 99 ) print ()
PS: 99 represent insertion, the output [99,11,22,33,44] 0 position.
- POP (delete a value, and can get the value deleted)
= li [11,22,33,44 ] v = li.pop () print (li) print (v)
PS: pop is to remove the last default parameters, can be added to delete parameter specifies the value of the output li [11,22,33], v 44 output.
- the Remove (delete the specified value in the list)
li = [11,22,33,22,44 ] li.remove ( 22 ) print (li)
PS: left side search, delete search stops, the output [11,33,22,44].
- Reverse (Flip list)
li = [11,22,33,44 ] li.reverse () print (li)
PS: Output [44,33,22,11].
- the Sort (sort the list)
it = [11,44,22,33 ,] li.sort () print (it) li.sort (reverse = True) print (you)
PS: Output [11,22,33,44] and [44,33,22,11], default from small to large.
4, tuple type tuple
- COUNT (get a specified number of characters that appear in the tuple)
tu = (11,22,33,22,44 ,) of = tu.count (22 ) print (in)
PS: Output 2.
- index (the index value acquisition position)
tu = (11,22,33,22,44 ,) of = tu.index (22 ) print (in)
PS: retrieve left side, to a given value when the index index is stopped, the output 1.
5, the dictionary dict
- fromkeys (a sequence of values to create a dictionary and specify unified under)
v = dict.fromkeys(["k1",123,"999"],123) print(v)
PS：输出{123:123,'k1':123,'999':123}，注意字典是无序的。
-get(根据key获取值)
dic = {"k1":'v1',"k2":'v2'}
v = dic.get('k1',111)
print(v)
PS：输出v1，如果k1不在字典里，则输出参数111，如无参数默认输出None。
-pop和popitem(删除并获取值)
dic = {"k1":'v1',"k2":'v2'}
v = dic.pop('k1',90)
print(dic,v)
k,v = dic.popitem()
print(dic,k,v)
PS：前者删除给定键的键值并返回值，如果不存在键则返回参数90；后者随机删除一对键值并返回键值对。
-setdefault(在字典中设置值)
dic = {"k1":'v1',"k2":'v2'}
v = dic.setdefault('k11','123')
print(dic,v)
PS：输出{'k1':'v1','k11':'123''','k2':'v2'} 123，若字典中包含给定键，则返回该键对应的值，否则返回为该键设置的值。
-update(更新字典)
dic = {"k1":'v1',"k2":'v2'}
dic.update(k1=123,k3=456,k5="asdf")
print(dic)
PS：输出{'k1':123,'k5':'asdf','k2':'v2','k3':345}，当字典里有给出的key时更新值，没有时则加入键值对。
-keys和values和items(提取字典的全部键、值、键值对)
dic = {"k1":'v1',"k2":'v2'}
v1 = dic.keys()
v2 = dic.values()
v3 = dic.items()
print(v1,v2,v3)
PS：字典还有clear(清除)、copy(拷贝)等用法和其他数据类型类似，就不提了(主要是懒)。