Python's commonly used built-in functions

Python built-in functions, which can be build-in Functions via Python's help document, can be viewed via commands under terminal interaction

>>> dir ("__builtins__") [' __add__ ', ' __class__ ', ' __contains__ ', ' __delattr__ ', ' __dir__ ', ' __doc__ ', ', _eq__ ', ' __format__ ', ' __ge__ ', ' __getattribute__ ', ' __getitem__ ', ' __getnewarg,__ ', ' __gt__ ', ' __hash__ ', ' __init__ ', ' __ iter__ ', ' __le__ ', ' __len__ ', ' __lt__, ' __mod__ ', ' __mul__ ', ' __ne__ ', ' __new__ ', ' __reduce__ ', ' __reduce_ex__ ', ' __epr_ ' _ ', ' __rmod__ ', ' __rmul__ ', ' __setattr__ ', ' __sizeof__ ', ' __str__ ', ' __subcasshook__ ', ' capitalize ', ' Casefold ', ' Center ', ' Count ', ' encode ', ' endswith ', expandtabs ', ' find ', ' format ', ' format_map ', ' index ', ' isalnum ', ' isalpha ', ' Isecimal ', ' isdigit ', ' isidentifier ', ' islower ', ' isnumeric ', ' isprintable ', ' issace ', ' istitle ', ' isupper ', ' join ', ' Ljust ', ' Lower ', ' Lstrip ', ' Maketrans ', ' prtition ', ' replace ', ' rfind ', ' rindex ', ' rjust ', ' rpartition ', ' rsplit ', ' Rstri ' ', ' Split ', ' splitlines ', ' startswith ', ' strip ', ' swapcase ', ' title ', ' Translat ', ' Upper ', ' Zfill ']

Python built-in functions can be divided into roughly several categories

Numeric operations

ABS ( -1) #取绝对值或者复数的模max ([5,2]), min ([[+]) #最大最小值len (' ABC '), len ([2,1]), len ((+)) #序列长度divmod (+/-) Built-in function to put ... Converted into a complex number, such as complex (' 2 ') return (2+0j), complex (' 2+3j ') returns (2+3j) POW () # built-in function, Exponentiation. If there is a third argument, the result of the exponentiation is the remainder of the third parameter, such as W (2,3) return 8,pow (2,3,4) returns the 0round (1)//1.0# floating-point number

Functional judgment

The callable ("variable") #函数是否可调用. Note: variables to be defined over isinstance (x,[11,22,33]) #判断X是不是有列表或者整型等, if yes, return true, not return falsecmp (' Hello ', ' Hello ') #比较 (x) range ([start,] stop[, step]) # Fast sequence generation

Type conversions

Long (x) float (x) #把: Convert to floating point complex (x)//plural str (x) #转换成字符串list (x) #转换成字符串tuple (x)//tuple-in-the-workpiece Conversion r = Hex (ten) #十六进制 r = Oct #八进制 r= bin (ten) #二进制 r= i NT (65) #十进制 i= int ("one", base=10) #进制间的相互转换base后跟 2/8/10/16 print (i) chr (x)//return x for the corresponding character, such as CHR (A.) return ' A ' ord (x)// Returns the ASC code number corresponding to the character, such as Ord (' A ') return 65# The most common example is the birth random verification code Import RANDOMTEMP = "" for i in range (4):    num = Random.randrange (0,4)    if num = = 3 or num = = 1:        li = random.randrange (0,10)        temp = temp + str (li)    else:        rad = Random.randran GE (65,91)        c = chr (rad)        temp + = Cprint (temp)

Sequence processing

Len (): sequence length max (): maximum min () in sequence: min. reduce (): merge filter (): filter sequence, Use the following def F1 (x):    # if x >:    #     return True    # else:    #     return False    return x >22# ret = Filter (f1,[11,22,33,44]) ret = filter (lambda x:x > 22, [ 11,22,33,44]) for i in ret:    print (i) map (): parallel traversal, can accept parameters of a function type, with the filter () function zip (): parallel traversal, usage specific as follows F1 = ["a", "b", "c"] F2 = [11,22,33]set = Zip (f1,f2) for i in set:    print (i)

Type () returns a data type, and so on

　

　

　　

　　

　　

Python's commonly used built-in functions