总结Python数据类型及其方法

python2中
number = 123print (type(number))
number2 = 2147483647print (type(number2))
number2 = 2147483648    #我们会看到超过2147483647这个范围，在py2中整形就会变成长整形了print (type(number2))#运行结果<type 'int'>
<type 'int'>
<type 'long'>#python3中number = 123print (type(number))
number2 = 2147483648   
print (type(number2))    #在python3中并不会#运行结果<class 'int'>
<class 'int'>

  def bit_length(self): # real signature unknown; restored from __doc__"""int.bit_length() -> int
        
        Number of bits necessary to represent self in binary.
        >>> bin(37)
        '0b100101'
        >>> (37).bit_length()
        6"""return 0

number = 12  #1100 print(number.bit_length())#运行结果4

#浮点型number = 1.1print(type(number))#运行结果<class 'float'>

    def as_integer_ratio(self): # real signature unknown; restored from __doc__"""float.as_integer_ratio() -> (int, int)
        
        Return a pair of integers, whose ratio is exactly equal to the original
        float and with a positive denominator.
        Raise OverflowError on infinities and a ValueError on NaNs.
        
        >>> (10.0).as_integer_ratio()
        (10, 1)
        >>> (0.0).as_integer_ratio()
        (0, 1)
        >>> (-.25).as_integer_ratio()
        (-1, 4)"""pass

number = 0.25print(number.as_integer_ratio())#运行结果(1, 4)

    def hex(self): # real signature unknown; restored from __doc__"""float.hex() -> string
        
        Return a hexadecimal representation of a floating-point number.
        >>> (-0.1).hex()
        '-0x1.999999999999ap-4'
        >>> 3.14159.hex()
        '0x1.921f9f01b866ep+1'"""return ""

number = 3.1415print(number.hex())#运行结果0x1.921cac083126fp+1

    def fromhex(string): # real signature unknown; restored from __doc__"""float.fromhex(string) -> float
        
        Create a floating-point number from a hexadecimal string.
        >>> float.fromhex('0x1.ffffp10')
        2047.984375
        >>> float.fromhex('-0x1p-1074')
        -5e-324"""

print(float.fromhex('0x1.921cac083126fp+1'))#运行结果3.1415

    def is_integer(self, *args, **kwargs): # real signature unknown""" Return True if the float is an integer. """pass

number = 3.1415number2 = 3.0print(number.is_integer())print(number2.is_integer())#运行结果False
True

name = 'my name is Frank'name1 = "my name is Frank"name2 = '''my name is Frank
I'm 23 years old,      
       '''print(name)print(name1)print(name2)#运行结果my name is Frank
my name is Frank
my name is Frank
I'm 23 years old

  def capitalize(self): # real signature unknown; restored from __doc__"""S.capitalize() -> str
        
        Return a capitalized version of S, i.e. make the first character
        have upper case and the rest lower case."""return ""

name = 'my name is Frank'#运行结果My name is frank

  def center(self, width, fillchar=None): # real signature unknown; restored from __doc__"""S.center(width[, fillchar]) -> str
        
        Return S centered in a string of length width. Padding is
        done using the specified fill character (default is a space)"""return ""

flag = "Welcome Frank"print(flag.center(50,'*'))#运行结果******************Welcome Frank*******************

    def count(self, sub, start=None, end=None): # real signature unknown; restored from __doc__"""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

flag = 'aaababbcccaddadaddd'print(flag.count('a'))print(flag.count('a',0,3))#运行结果7
3

    def encode(self, encoding='utf-8', errors='strict'): # real signature unknown; restored from __doc__"""S.encode(encoding='utf-8', errors='strict') -> bytes
        
        Encode S using the codec registered for encoding. Default encoding
        is 'utf-8'. 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 can handle UnicodeEncodeErrors."""return b""

flag = 'aaababbcccaddadaddd'print(flag.encode('utf8'))#运行结果b'aaababbcccaddadaddd'

   def endswith(self, suffix, start=None, end=None): # real signature unknown; restored from __doc__"""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

flag = 'aaababbcccaddadaddd'print(flag.endswith('aa'))print(flag.endswith('ddd'))print(flag.endswith('dddd'))print(flag.endswith('aaa',0,3))print(flag.endswith('aaa',0,2))#运行结果False
True
False
True
False

  def expandtabs(self, tabsize=8): # real signature unknown; restored from __doc__"""S.expandtabs(tabsize=8) -> str
        
        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 ""

flag = "\thello python!"print(flag)print(flag.expandtabs())   #默认tabsize=8print(flag.expandtabs(20))#运行结果hello python!             #一个tab，长度为4个空格hello python!         #8个空格hello python!    #20个空格

    def find(self, sub, start=None, end=None): # real signature unknown; restored from __doc__"""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

flag = "hello python!"print(flag.find('e'))print(flag.find('a'))print(flag.find('h',4,-1))#运行结果1
-1
9

def format(self, *args, **kwargs): # known special case of str.format"""S.format(*args, **kwargs) -> str
        
        Return a formatted version of S, using substitutions from args and kwargs.
        The substitutions are identified by braces ('{' and '}')."""pass

#位置参数flag = "hello {0} and {1}!"print(flag.format('python','php'))
flag = "hello {} and {}!"print(flag.format('python','php'))#变量参数flag = "{name} is {age} years old!"print(flag.format(name='Frank',age = 23))#结合列表infor=["Frank",23]print("{0[0]} is {0[1]} years old".format(infor))#运行结果hello python and php!
hello python and php!
Frank is 23 years old!
Frank is 23 years old

 def format_map(self, mapping): # real signature unknown; restored from __doc__"""S.format_map(mapping) -> str
        
        Return a formatted version of S, using substitutions from mapping.
        The substitutions are identified by braces ('{' and '}')."""return ""

people={'name':['Frank','Caroline'],'age':['23','22'],
}print("My name is {name[0]},i am {age[1]} years old !".format_map(people))#运行结果My name is Frank,i am 22 years old !

 def index(self, sub, start=None, end=None): # real signature unknown; restored from __doc__"""S.index(sub[, start[, end]]) -> int
        
        Like S.find() but raise ValueError when the substring is not found."""return 0

flag = "hello python!"print(flag.index("e"))print(flag.index("o",6,-1))#运行结果1
10

def isalnum(self): # real signature unknown; restored from __doc__"""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

flag = "hellopython"flag1 = "hellopython22"flag2 = "hellopython!!"flag3 = "!@#!#@!!@"print(flag.isalnum())print(flag1.isalnum())print(flag2.isalnum())print(flag3.isalnum())#运行结果True
True
False
False

 def isalpha(self): # real signature unknown; restored from __doc__"""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

flag = "hellopython"flag1 = "hellopython22"print(flag.isalpha())print(flag1.isalpha())#运行结果True
False

  def isdecimal(self): # real signature unknown; restored from __doc__"""S.isdecimal() -> bool
        
        Return True if there are only decimal characters in S,
        False otherwise."""return False

number = "1.2"number1 = "12"number2 = "-12"number3 = "1222"print(number.isdecimal())print(number1.isdecimal())print(number2.isdecimal())print(number3.isdecimal())#运行结果False
True
False
True

  def isdigit(self): # real signature unknown; restored from __doc__"""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

number = "1.2"number1 = "12"number2 = "-12"number3 = "11"print(number.isdigit())print(number1.isdigit())print(number2.isdigit())print(number3.isdigit())#运行结果False
True
False
True

 def isidentifier(self): # real signature unknown; restored from __doc__"""S.isidentifier() -> bool
        
        Return True if S is a valid identifier according
        to the language definition.
        
        Use keyword.iskeyword() to test for reserved identifiers
        such as "def" and "class"."""return False

flag = "cisco"flag1 = "1cisco"flag2 = "print"print(flag.isidentifier())print(flag1.isidentifier())print(flag2.isidentifier())#运行结果True
False
True

    def islower(self): # real signature unknown; restored from __doc__"""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

flag = "cisco"flag1 = "cisco222"flag2 = "Cisco"print(flag.islower())print(flag1.islower())print(flag2.islower())#运行结果True
True
False

 def isnumeric(self): # real signature unknown; restored from __doc__"""S.isnumeric() -> bool
        
        Return True if there are only numeric characters in S,
        False otherwise."""return False

number = "123"number1 = "一"number2 = "壹"number3 = "123q"number4 = "1.1"print(number.isnumeric())print(number1.isnumeric())print(number2.isnumeric())print(number3.isnumeric())print(number4.isnumeric())#运行结果True
True
True
False
False

   def isprintable(self): # real signature unknown; restored from __doc__"""S.isprintable() -> bool
        
        Return True if all characters in S are considered
        printable in repr() or S is empty, False otherwise."""return False

flag = "\n123"flag1 = "\t"flag2 = "123"flag3 = r"\n123"    # r 可以是转义字符失效print(flag.isprintable())     #\n不可打印print(flag1.isprintable())    #\t不可打印print(flag2.isprintable())print(flag3.isprintable())#运行结果False
False
True
True

  def isspace(self): # real signature unknown; restored from __doc__"""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

flag = '    '     #4个空格flag1 = '        '#2个tabprint(flag.isspace())print(flag1.isspace())#运行结果True
True

  def isspace(self): # real signature unknown; restored from __doc__"""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

flag = "Welcome Frank"flag1 = "Welcome frank"print(flag.istitle())print(flag1.istitle())#运行结果True
False

    def isupper(self): # real signature unknown; restored from __doc__"""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

flag = "WELCOME1"flag1 = "Welcome1"print(flag.isupper())print(flag1.isupper())#运行结果True
False

  def join(self, iterable): # real signature unknown; restored from __doc__"""S.join(iterable) -> str
        
        Return a string which is the concatenation of the strings in the
        iterable.  The separator between elements is S."""return ""

flag = "welcome"print("#".join(flag))#运行结果w#e#l#c#o#m#e

   def ljust(self, width, fillchar=None): # real signature unknown; restored from __doc__"""S.ljust(width[, fillchar]) -> str
        
        Return S left-justified in a Unicode string of length width. Padding is
        done using the specified fill character (default is a space)."""return ""

flag = "welcome"print(flag.ljust(20,"*"))#运行结果welcome*************

    def rjust(self, width, fillchar=None): # real signature unknown; restored from __doc__"""S.rjust(width[, fillchar]) -> str
        
        Return S right-justified in a string of length width. Padding is
        done using the specified fill character (default is a space)."""return ""

flag = "welcome"print(flag.rjust(20,"*"))#运行结果*************welcome

    def lower(self): # real signature unknown; restored from __doc__"""S.lower() -> str
        
        Return a copy of the string S converted to lowercase."""return ""

flag = "WELcome"#运行结果welcome

    def upper(self): # real signature unknown; restored from __doc__"""S.upper() -> str
        
        Return a copy of S converted to uppercase."""return ""

flag = "WELcome"print(flag.upper())#运行结果WELCOME

    def title(self): # real signature unknown; restored from __doc__"""S.title() -> str
        
        Return a titlecased version of S, i.e. words start with title case
        characters, all remaining cased characters have lower case."""return ""

flag = "welcome frank"print(flag.title())#运行结果Welcome Frank

  def lstrip(self, chars=None): # real signature unknown; restored from __doc__"""S.lstrip([chars]) -> str
        
        Return a copy of the string S with leading whitespace removed.
        If chars is given and not None, remove characters in chars instead."""return ""

flag = "     welcome frank"flag1 = "@@@@welcome frank"print(flag.lstrip())print(flag.lstrip("@"))print(flag.lstrip("@").lstrip())#运行结果welcome frank
     welcome frank
welcome frank

 def rstrip(self, chars=None): # real signature unknown; restored from __doc__"""S.rstrip([chars]) -> str
        
        Return a copy of the string S with trailing whitespace removed.
        If chars is given and not None, remove characters in chars instead."""return ""

flag = "welcome frank    "flag1 = "welcome frank@@@@"# print(flag.title())print(flag.rstrip())print(flag.rstrip("@"))print(flag.rstrip("@").rstrip())#运行结果welcome frank
welcome frank    #右边有4个空格welcome frank

    def strip(self, chars=None): # real signature unknown; restored from __doc__"""S.strip([chars]) -> str
        
        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."""return ""

flag = "    welcome frank    "flag1 = "@@@@welcome frank@@@@"# print(flag.title())print(flag.strip())print(flag.strip("@"))print(flag.strip("@").strip())#运行结果welcome frank
    welcome frank    #右边有4个空格welcome frank

   def maketrans(self, *args, **kwargs): # real signature unknown"""Return a translation table usable for str.translate().
        
        If there is only one argument, it must be a dictionary mapping Unicode
        ordinals (integers) or characters to Unicode ordinals, strings or None.
        Character keys will be then converted to ordinals.
        If there are two arguments, they must be strings of equal length, and
        in the resulting dictionary, each character in x will be mapped to the
        character at the same position in y. If there is a third argument, it
        must be a string, whose characters will be mapped to None in the result."""pass

  def translate(self, table): # real signature unknown; restored from __doc__"""S.translate(table) -> str
        
        Return a copy of the string S in which each character has been mapped
        through the given translation table. The table must implement
        lookup/indexing via __getitem__, for instance a dictionary or list,
        mapping Unicode ordinals to Unicode ordinals, strings, or None. If
        this operation raises LookupError, the character is left untouched.
        Characters mapped to None are deleted."""return ""

intab = "aeiou"outtab = "12345"trantab = str.maketrans(intab, outtab)
str = "this is string example....wow!!!"print (str.translate(trantab))#运行结果th3s 3s str3ng 2x1mpl2....w4w!!!