# Python 数据类型¶

## 进制¶

• 二进制，01
• 八进制，01234567
• 十进制，0123456789
• 十六进制，012345678910ABCDEF

## 整数¶

In [ ]:
class int(object):
"""
int(x=0) -> int or long
int(x, base=10) -> int or long

Convert a number or string to an integer, or return 0 if no arguments
are given.  If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.

If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base.  The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
"""
def bit_length(self):
""" 返回表示该数字的时占用的最少位数 """
"""
int.bit_length() -> int

Number of bits necessary to represent self in binary.
>>> bin(37)
'0b100101'
>>> (37).bit_length()
"""
return 0

def conjugate(self, *args, **kwargs): # real signature unknown
""" 返回该复数的共轭复数 """
""" Returns self, the complex conjugate of any int. """
pass

def __abs__(self):
""" 返回绝对值 """
""" x.__abs__() <==> abs(x) """
pass

pass

def __and__(self, y):
""" x.__and__(y) <==> x&y """
pass

def __cmp__(self, y):
""" 比较两个数大小 """
""" x.__cmp__(y) <==> cmp(x,y) """
pass

def __coerce__(self, y):
""" 强制生成一个元组 """
""" x.__coerce__(y) <==> coerce(x, y) """
pass

def __divmod__(self, y):
""" 相除，得到商和余数组成的元组 """
""" x.__divmod__(y) <==> divmod(x, y) """
pass

def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass

def __float__(self):
""" 转换为浮点类型 """
""" x.__float__() <==> float(x) """
pass

def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass

def __format__(self, *args, **kwargs): # real signature unknown
pass

def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass

def __getnewargs__(self, *args, **kwargs): # real signature unknown
""" 内部调用 __new__方法或创建对象时传入参数使用 """
pass

def __hash__(self):
"""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。"""
""" x.__hash__() <==> hash(x) """
pass

def __hex__(self):
""" 返回当前数的 十六进制 表示 """
""" x.__hex__() <==> hex(x) """
pass

def __index__(self):
""" 用于切片，数字无意义 """
""" x[y:z] <==> x[y.__index__():z.__index__()] """
pass

def __init__(self, x, base=10): # known special case of int.__init__
""" 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """
"""
int(x=0) -> int or long
int(x, base=10) -> int or long

Convert a number or string to an integer, or return 0 if no arguments
are given.  If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.

If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base.  The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
# (copied from class doc)
"""
pass

def __int__(self):
""" 转换为整数 """
""" x.__int__() <==> int(x) """
pass

def __invert__(self):
""" x.__invert__() <==> ~x """
pass

def __long__(self):
""" 转换为长整数 """
""" x.__long__() <==> long(x) """
pass

def __lshift__(self, y):
""" x.__lshift__(y) <==> x<<y """
pass

def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass

def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass

def __neg__(self):
""" x.__neg__() <==> -x """
pass

@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass

def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass

def __oct__(self):
""" 返回改值的 八进制 表示 """
""" x.__oct__() <==> oct(x) """
pass

def __or__(self, y):
""" x.__or__(y) <==> x|y """
pass

def __pos__(self):
""" x.__pos__() <==> +x """
pass

def __pow__(self, y, z=None):
""" 幂，次方 """
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass

pass

def __rand__(self, y):
""" x.__rand__(y) <==> y&x """
pass

def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass

def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass

def __repr__(self):
"""转化为解释器可读取的形式 """
""" x.__repr__() <==> repr(x) """
pass

def __str__(self):
"""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"""
""" x.__str__() <==> str(x) """
pass

def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass

def __rlshift__(self, y):
""" x.__rlshift__(y) <==> y<<x """
pass

def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass

def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass

def __ror__(self, y):
""" x.__ror__(y) <==> y|x """
pass

def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass

def __rrshift__(self, y):
""" x.__rrshift__(y) <==> y>>x """
pass

def __rshift__(self, y):
""" x.__rshift__(y) <==> x>>y """
pass

def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass

def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass

def __rxor__(self, y):
""" x.__rxor__(y) <==> y^x """
pass

def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass

def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass

def __trunc__(self, *args, **kwargs):
""" 返回数值被截取为整形的值，在整形中无意义 """
pass

def __xor__(self, y):
""" x.__xor__(y) <==> x^y """
pass

denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
""" 分母 = 1 """
"""the denominator of a rational number in lowest terms"""

imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
""" 虚数，无意义 """
"""the imaginary part of a complex number"""

numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
""" 分子 = 数字大小 """
"""the numerator of a rational number in lowest terms"""

real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
""" 实属，无意义 """
"""the real part of a complex number"""

int


## 浮点型¶

In [ ]:
class float(object):
"""
float(x) -> floating point number

Convert a string or number to a floating point number, if possible.
"""
def as_integer_ratio(self):
""" 获取改值的最简比 """
"""
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

def conjugate(self, *args, **kwargs): # real signature unknown
""" Return self, the complex conjugate of any float. """
pass

def fromhex(self, string):
""" 将十六进制字符串转换成浮点型 """
"""
float.fromhex(string) -> float

Create a floating-point number from a hexadecimal string.
>>> float.fromhex('0x1.ffffp10')
2047.984375
>>> float.fromhex('-0x1p-1074')
-4.9406564584124654e-324
"""
return 0.0

def hex(self):
""" 返回当前值的 16 进制表示 """
"""
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 ""

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

def __abs__(self):
""" x.__abs__() <==> abs(x) """
pass

pass

def __coerce__(self, y):
""" x.__coerce__(y) <==> coerce(x, y) """
pass

def __divmod__(self, y):
""" x.__divmod__(y) <==> divmod(x, y) """
pass

def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass

def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass

def __float__(self):
""" x.__float__() <==> float(x) """
pass

def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass

def __format__(self, format_spec):
"""
float.__format__(format_spec) -> string

Formats the float according to format_spec.
"""
return ""

def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass

def __getformat__(self, typestr):
"""
float.__getformat__(typestr) -> string

You probably don't want to use this function.  It exists mainly to be
used in Python's test suite.

typestr must be 'double' or 'float'.  This function returns whichever of
'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the
format of floating point numbers used by the C type named by typestr.
"""
return ""

def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass

def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass

def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass

def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass

def __init__(self, x):
pass

def __int__(self):
""" x.__int__() <==> int(x) """
pass

def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass

def __long__(self):
""" x.__long__() <==> long(x) """
pass

def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass

def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass

def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass

def __neg__(self):
""" x.__neg__() <==> -x """
pass

@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass

def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass

def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass

def __pos__(self):
""" x.__pos__() <==> +x """
pass

def __pow__(self, y, z=None):
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass

pass

def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass

def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass

def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass

def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass

def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass

def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass

def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass

def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass

def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass

def __setformat__(self, typestr, fmt):
"""
float.__setformat__(typestr, fmt) -> None

You probably don't want to use this function.  It exists mainly to be
used in Python's test suite.

typestr must be 'double' or 'float'.  fmt must be one of 'unknown',
'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be
one of the latter two if it appears to match the underlying C reality.

Override the automatic determination of C-level floating point type.
This affects how floats are converted to and from binary strings.
"""
pass

def __str__(self):
""" x.__str__() <==> str(x) """
pass

def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass

def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass

def __trunc__(self, *args, **kwargs): # real signature unknown
""" Return the Integral closest to x between 0 and x. """
pass

imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
"""the imaginary part of a complex number"""

real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
"""the real part of a complex number"""

float

float


## 算数运算¶

In [1]:
a = 10
b = 20

a + b
a - b
a * b
b / a
b % a
a ** b
9 // 2
9.0 // 2.0

Out[1]:
30
Out[1]:
-10
Out[1]:
200
Out[1]:
2.0
Out[1]:
0
Out[1]:
100000000000000000000
Out[1]:
4
Out[1]:
4.0

## 字符串¶

In [2]:
# 空字符串
s = ''
s
s = ""
s

Out[2]:
''
Out[2]:
''
In [3]:
# 字符串中包含引号
s1 = "what's you name?"
s2 = 'my name is "liangxiansen"'

print(s1, s2, sep='\n')

what's you name?
my name is "liangxiansen"

In [4]:
# 三重引号字符串块

s3 = """
Infomation of user liangxiansen:
-------------------
Name:   liangxiansen
Age :   12
Job :   Programmer
---------End-------
"""

print(s3)

Infomation of user liangxiansen:
-------------------
Name:   liangxiansen
Age :   12
Job :   Programmer
---------End-------


In [5]:
# Raw字符串，可以对字符串中的特殊字符转义
s4 = r'liangxiansen \n'
s4

Out[5]:
'liangxiansen \\n'
In [6]:
# Unicode 字符串
s5 = u'liangxiansen'
s5

Out[6]:
'liangxiansen'
In [7]:
# 字节字符串
s6 = b'liangxiansen'
s6

Out[7]:
b'liangxiansen'

In [ ]:
class str(basestring):
"""
str(object='') -> string

Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
"""
def capitalize(self):
""" 首字母变大写 """
"""
S.capitalize() -> string

Return a copy of the string S with only its first character
capitalized.
"""
return ""

def center(self, width, fillchar=None):
""" 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """
"""
S.center(width[, fillchar]) -> string

Return S centered in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return ""

def count(self, sub, start=None, end=None):
""" 子序列个数 """
"""
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

def decode(self, encoding=None, errors=None):
""" 解码 """
"""
S.decode([encoding[,errors]]) -> object

Decodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
as well as any other name registered with codecs.register_error that is
able to handle UnicodeDecodeErrors.
"""
return object()

def encode(self, encoding=None, errors=None):
""" 编码，针对unicode """
"""
S.encode([encoding[,errors]]) -> object

Encodes S using the codec registered for encoding. encoding defaults
to the default encoding. 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 is able to handle UnicodeEncodeErrors.
"""
return object()

def endswith(self, suffix, start=None, end=None):
""" 是否以 xxx 结束 """
"""
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

def expandtabs(self, tabsize=None):
""" 将tab转换成空格，默认一个tab转换成8个空格 """
"""
S.expandtabs([tabsize]) -> string

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 ""

def find(self, sub, start=None, end=None):
""" 寻找子序列位置，如果没找到，则异常 """
"""
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

def format(*args, **kwargs): # known special case of str.format
""" 字符串格式化，动态参数，将函数式编程时细说 """
"""
S.format(*args, **kwargs) -> string

Return a formatted version of S, using substitutions from args and kwargs.
The substitutions are identified by braces ('{' and '}').
"""
pass

def index(self, sub, start=None, end=None):
""" 子序列位置，如果没找到，则返回-1  """
S.index(sub [,start [,end]]) -> int

"""
return 0

def isalnum(self):
""" 是否是字母和数字 """
"""
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

def isalpha(self):
""" 是否是字母 """
"""
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

def isdigit(self):
""" 是否是数字 """
"""
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

def islower(self):
""" 是否小写 """
"""
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

def isspace(self):
"""
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

def istitle(self):
"""
S.istitle() -> bool

Return True if S is a titlecased string and there is at least one
character in S, i.e. uppercase characters may only follow uncased
characters and lowercase characters only cased ones. Return False
otherwise.
"""
return False

def isupper(self):
"""
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

def join(self, iterable):
""" 连接 """
"""
S.join(iterable) -> string

Return a string which is the concatenation of the strings in the
iterable.  The separator between elements is S.
"""
return ""

def ljust(self, width, fillchar=None):
""" 内容左对齐，右侧填充 """
"""
S.ljust(width[, fillchar]) -> string

Return S left-justified in a string of length width. Padding is
done using the specified fill character (default is a space).
"""
return ""

def lower(self):
""" 变小写 """
"""
S.lower() -> string

Return a copy of the string S converted to lowercase.
"""
return ""

def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
S.lstrip([chars]) -> string or unicode

Return a copy of the string S with leading whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""

def partition(self, sep):
""" 分割，前，中，后三部分 """
"""

Search for the separator sep in S, and return the part before it,
the separator itself, and the part after it.  If the separator is not
found, return S and two empty strings.
"""
pass

def replace(self, old, new, count=None):
""" 替换 """
"""
S.replace(old, new[, count]) -> string

Return a copy of string S with all occurrences of substring
old replaced by new.  If the optional argument count is
given, only the first count occurrences are replaced.
"""
return ""

def rfind(self, sub, start=None, end=None):
"""
S.rfind(sub [,start [,end]]) -> int

Return the highest 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

def rindex(self, sub, start=None, end=None):
"""
S.rindex(sub [,start [,end]]) -> int

"""
return 0

def rjust(self, width, fillchar=None):
"""
S.rjust(width[, fillchar]) -> string

Return S right-justified in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return ""

def rpartition(self, sep):
"""

Search for the separator sep in S, starting at the end of S, and return
the part before it, the separator itself, and the part after it.  If the
"""
pass

def rsplit(self, sep=None, maxsplit=None):
"""
S.rsplit([sep [,maxsplit]]) -> list of strings

Return a list of the words in the string S, using sep as the
delimiter string, starting at the end of the string and working
to the front.  If maxsplit is given, at most maxsplit splits are
done. If sep is not specified or is None, any whitespace string
is a separator.
"""
return []

def rstrip(self, chars=None):
"""
S.rstrip([chars]) -> string or unicode

Return a copy of the string S with trailing whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""

def split(self, sep=None, maxsplit=None):
""" 分割， maxsplit最多分割几次 """
"""
S.split([sep [,maxsplit]]) -> list of strings

Return a list of the words in the string S, using sep as the
delimiter string.  If maxsplit is given, at most maxsplit
splits are done. If sep is not specified or is None, any
whitespace string is a separator and empty strings are removed
from the result.
"""
return []

def splitlines(self, keepends=False):
""" 根据换行分割 """
"""
S.splitlines(keepends=False) -> list of strings

Return a list of the lines in S, breaking at line boundaries.
Line breaks are not included in the resulting list unless keepends
is given and true.
"""
return []

def startswith(self, prefix, start=None, end=None):
""" 是否起始 """
"""
S.startswith(prefix[, start[, end]]) -> bool

Return True if S starts with the specified prefix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
prefix can also be a tuple of strings to try.
"""
return False

def strip(self, chars=None):
""" 移除两段空白 """
"""
S.strip([chars]) -> string or unicode

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.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""

def swapcase(self):
""" 大写变小写，小写变大写 """
"""
S.swapcase() -> string

Return a copy of the string S with uppercase characters
converted to lowercase and vice versa.
"""
return ""

def title(self):
"""
S.title() -> string

characters, all remaining cased characters have lowercase.
"""
return ""

def translate(self, table, deletechars=None):
"""
转换，需要先做一个对应表，最后一个表示删除字符集合
intab = "aeiou"
outtab = "12345"
trantab = maketrans(intab, outtab)
str = "this is string example....wow!!!"
print str.translate(trantab, 'xm')
"""

"""
S.translate(table [,deletechars]) -> string

Return a copy of the string S, where all characters occurring
in the optional argument deletechars are removed, and the
remaining characters have been mapped through the given
translation table, which must be a string of length 256 or None.
If the table argument is None, no translation is applied and
the operation simply removes the characters in deletechars.
"""
return ""

def upper(self):
"""
S.upper() -> string

Return a copy of the string S converted to uppercase.
"""
return ""

def zfill(self, width):
"""方法返回指定长度的字符串，原字符串右对齐，前面填充0。"""
"""
S.zfill(width) -> string

Pad a numeric string S with zeros on the left, to fill a field
of the specified width.  The string S is never truncated.
"""
return ""

def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
pass

def _formatter_parser(self, *args, **kwargs): # real signature unknown
pass

pass

def __contains__(self, y):
""" x.__contains__(y) <==> y in x """
pass

def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass

def __format__(self, format_spec):
"""
S.__format__(format_spec) -> string

Return a formatted version of S as described by format_spec.
"""
return ""

def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass

def __getitem__(self, y):
""" x.__getitem__(y) <==> x[y] """
pass

def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass

def __getslice__(self, i, j):
"""
x.__getslice__(i, j) <==> x[i:j]

Use of negative indices is not supported.
"""
pass

def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass

def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass

def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass

def __init__(self, string=''): # known special case of str.__init__
"""
str(object='') -> string

Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
# (copied from class doc)
"""
pass

def __len__(self):
""" x.__len__() <==> len(x) """
pass

def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass

def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass

def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass

def __mul__(self, n):
""" x.__mul__(n) <==> x*n """
pass

@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass

def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass

def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass

def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass

def __rmul__(self, n):
""" x.__rmul__(n) <==> n*x """
pass

def __sizeof__(self):
""" S.__sizeof__() -> size of S in memory, in bytes """
pass

def __str__(self):
""" x.__str__() <==> str(x) """
pass

str

In [8]:
# 字符串拼接
LastName = 'Liang'
FirstName = 'Kevin'

MyName = FirstName + ' ' + LastName
print(MyName)

Kevin Liang

In [9]:
# 字符串重复
print('liang' * 3)

liangliangliang

In [10]:
# 字符串长度
len('liang')

Out[10]:
5

In [11]:
str1 = 'liang'
str1[0]
str1[1]
str1[2]
str1[3]
str1[4]

Out[11]:
'l'
Out[11]:
'i'
Out[11]:
'a'
Out[11]:
'n'
Out[11]:
'g'

In [12]:
str1[0:3]

Out[12]:
'lia'
In [13]:
# 取中间到最后
str2 = 'liangxiang'
length = len(str2)
mid = length // 2
print(str2[mid:])

xiang


In [14]:
# 取从开头到中间
print(str2[:mid])

liang


In [15]:
str2[-9:-2]

Out[15]:
'iangxia'

str[起始索引:结束索引:步长]

In [16]:
# 隔一个字符选取
print(str2)
print(str2[::2])

liangxiang
lagin


In [17]:
str2[::-1]

Out[17]:
'gnaixgnail'
In [18]:
str2[2:5]
str2[4:1:-1]
str2[4::-1]

Out[18]:
'ang'
Out[18]:
'gna'
Out[18]:
'gnail'

In [19]:
# 字符串strip方法去除字符串两端的空格
"   liangxiansen   ".strip()
"   liangxiansen   ".lstrip() # 去掉字符串左边的空格
"   liangxiansen   ".rstrip() # 去掉字符串右边的空格

Out[19]:
'liangxiansen'
Out[19]:
'liangxiansen   '
Out[19]:
'   liangxiansen'
In [20]:
# 字符串split方法分隔字符串返回list
"  Kevin liang  ".split() # 默认参数为空格，以空格分割字符串。
"liang#xian#sen".split('#')  # 也可以传一个字符，通过这个字符分割字符串

Out[20]:
['Kevin', 'liang']
Out[20]:
['liang', 'xian', 'sen']
In [21]:
# 字符串join方法来对字符串进行拼接
name_list = " Kevin Liang ".split()   # 分隔字符串
new_name = "/".join(name_list)  # 拼接字符串
print(new_name)

Kevin/Liang

In [22]:
# 字符串find方法得到字符在字符串中得索引
name = "Kevin Liang"
name.find('v')

Out[22]:
2
In [23]:
# 字符串replace方法字符串替换
name.replace('iang', 'ing') # 需要注意的是，replace 并不是在原字符串上修改，而是基于原字符串返回一个修改后的新字符串

Out[23]:
'Kevin Ling'
In [24]:
# 字符串center方法来对字符串居中
name.center(30, '=') # 第一个参数设置字符串宽度，第二个参数设置填充空白的字符串，不传默认为空格

Out[24]:
'=========Kevin Liang=========='
In [25]:
print("是否‘K‘开头：\t", name.startswith('K')) # 判断什么字符开头
print("是否‘g’结尾：\t", name.endswith('g'))   # 判断什么字符结尾
print("没有特殊字符：\t", name.isalnum())      # 是否全是字母和数字，并至少有一个字符
print("是否全是字母：\t", name.isalpha())      # 是否全是字母，并至少有一个字符
print("是否全是数字：\t", name.isdigit())      # 是否全是数字，并至少有一个字符
print("是否全空白字符：\t", name.isspace())    # 是否全是空白字符，并至少有一个字符
print("是否全是小写：\t", name.islower())     # 中的字母是否全是小写
print("是否全是大写：\t", name.isupper())     # 中的字母是否便是大写
print("是否首字母大写：\t", name.istitle())   # 是否是首字母大写的

是否‘K‘开头：	 True


In [26]:
print(name)
name.swapcase()   # 大小写互换
name.title()      # 单词首字母大写
name.capitalize() # 字符串首字母大写，其余字符小写
name.upper()      # 全部字符转变为大写
name.lower()      # 全部字符转变为小写

Kevin Liang

Out[26]:
'kEVIN lIANG'
Out[26]:
'Kevin Liang'
Out[26]:
'Kevin liang'
Out[26]:
'KEVIN LIANG'
Out[26]:
'kevin liang'

## 元组¶

In [27]:
# 创建元组
t = (1, 2, 3, 'liang')
type(t)

Out[27]:
tuple

In [28]:
t1 = (1)
type(t1)

Out[28]:
int

In [29]:
t2 = (1,)
type(t2)

Out[29]:
tuple

In [30]:
t3 = tuple()
t4 = tuple('liang')
type(t3)
type(t4)

t3
t4

Out[30]:
tuple
Out[30]:
tuple
Out[30]:
()
Out[30]:
('l', 'i', 'a', 'n', 'g')

In [31]:
# 元组嵌套
tp = (1, 2, 3, 4, 5, 6, 7, 8, 9, (1, 2, 3),)
print(tp[0])      # []中输入索引进行分片,索引起始位为0
print(tp[3:6])    # 显示4~6得元素
print(tp[3:])     # 显示4到最后
print(tp[:6])     # 显示从开头到7的元素
print(tp[-1])     # 显示倒数第一个
print(tp[-4:-2])  # 显示倒数第4个到倒数第二个,(范围切片,结束位不包括在内,即"到什么什么之前")
print(tp[:])      # 显示全部
print(tp[::2])    # 按照步长为2,显示全部,步长即两个元素之间索引闲差多少执行一次
print(tp[9][0])   # 嵌套分片

1
(4, 5, 6)
(4, 5, 6, 7, 8, 9, (1, 2, 3))
(1, 2, 3, 4, 5, 6)
(1, 2, 3)
(7, 8)
(1, 2, 3, 4, 5, 6, 7, 8, 9, (1, 2, 3))
(1, 3, 5, 7, 9)
1

In [32]:
# index方法查找元素相对应得索引
tp.index(9)

Out[32]:
8
In [33]:
# count查看元素在元组中得数量
tp.count(3)

Out[33]:
1

## 列表¶

List 是Python 中最灵活的有序的集合，列表可以包含任何类型的对象：数字、字符串、甚至其他列表。支持在原处修改（可修改的），也可以进行分片操作

List书写格式用 [ ] 包裹起来,元素与元素之间用 "," 逗号分隔：

In [34]:
l = []
type(l)

Out[34]:
list

list 函数还可以将其他序列转换成列表：

In [35]:
list('liang')
list((1, 2, 3, 4, ))

Out[35]:
['l', 'i', 'a', 'n', 'g']
Out[35]:
[1, 2, 3, 4]

In [36]:
# 创建了换一个List， 而且里面还嵌套了List
list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, [10, 11, 22, 33, 44]]

list1[0]
list1[1]
list1[3:6]
list1[3:]
list1[:6]
list1[-1][0]
list1[-9:-4]
list1[::-1]
list1[::2]

Out[36]:
1
Out[36]:
2
Out[36]:
[4, 5, 6]
Out[36]:
[4, 5, 6, 7, 8, 9, [10, 11, 22, 33, 44]]
Out[36]:
[1, 2, 3, 4, 5, 6]
Out[36]:
10
Out[36]:
[2, 3, 4, 5, 6]
Out[36]:
[[10, 11, 22, 33, 44], 9, 8, 7, 6, 5, 4, 3, 2, 1]
Out[36]:
[1, 3, 5, 7, 9]

In [37]:
list1[0] = 111
print(list1)

[111, 2, 3, 4, 5, 6, 7, 8, 9, [10, 11, 22, 33, 44]]

In [38]:
# 列表append方法对列表中添加元素

list2 = ['Kevin', 'Lina', 'Eric', 'Alex', 'Lina']
list2.append('Liangxiansen')
print(list2)

['Kevin', 'Lina', 'Eric', 'Alex', 'Lina', 'Liangxiansen']

In [39]:
# 列表count方法查看指定元素在列表中的数量
list2.count('Lina')

Out[39]:
2
In [40]:
# 列表pop方法删除列表中的最后一个元素
print(list2)
list2.pop()
print(list2)

['Kevin', 'Lina', 'Eric', 'Alex', 'Lina', 'Liangxiansen']

Out[40]:
'Liangxiansen'
['Kevin', 'Lina', 'Eric', 'Alex', 'Lina']

In [41]:
# 列表remove方法删除列表指定元素,执行一次只会删除一个，默认是删除找到的第一个。
print(list2)
list2.remove('Lina')
print(list2)

['Kevin', 'Lina', 'Eric', 'Alex', 'Lina']
['Kevin', 'Eric', 'Alex', 'Lina']

In [42]:
# 列表index方法获取指定的元素的索引
list2.index('Alex')

Out[42]:
2
In [43]:
# 列表extend方法拼接列表
list2.extend(list1)
print(list2)

['Kevin', 'Eric', 'Alex', 'Lina', 111, 2, 3, 4, 5, 6, 7, 8, 9, [10, 11, 22, 33, 44]]

In [44]:
list2.sort()
print(list2)

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-44-c0dd03032db6> in <module>()
----> 1 list2.sort()
2 print(list2)

TypeError: unorderable types: int() < str()
In [45]:
list1.sort()

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-45-05e4223c8627> in <module>()
----> 1 list1.sort()

TypeError: unorderable types: list() < int()

In [46]:
list3 = [7, 3, 2, 6, 9, 0, 5, 1, 4, 8]
list3.sort()
print(list3)

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

In [47]:
# 列表reverse方法对列表进行反转
list3 = [7, 3, 2, 6, 9, 0, 5, 1, 4, 8]
list3[::-1]
list3.reverse()
print(list3)

Out[47]:
[8, 4, 1, 5, 0, 9, 6, 2, 3, 7]
[8, 4, 1, 5, 0, 9, 6, 2, 3, 7]


List 的reverse方法只会根据索引粗暴的反转 List， 并不会做排序，和分片 [::-1] 效果一样

In [48]:
# 列表insert方法在列表的指定位置插入新值。
print(list3)
list3.insert(2, '66') # 接收两个参数，第一个是索引，第二个是值，
print(list3)

[8, 4, 1, 5, 0, 9, 6, 2, 3, 7]
[8, 4, '66', 1, 5, 0, 9, 6, 2, 3, 7]

In [49]:
# 列表clear方法清空列表
list3.clear()
print(list3)

[]


In [53]:
# 使用递归遍历多层嵌套List，把所有的9替换成9999
that_list = [1, 5, [9, 4, 3, 5, [9, 8, [88, 9, 2], 3, 5], 2, 6], 9, [3, 6, 9, [9, 2], 3], 8]  # 创建多层嵌套list

# 创建递归函数
def change_all(ll):
for i in ll:
if i == 9:
key = ll.index(i)
ll[key] = 9999
elif isinstance(i, list):  # 如果该对象是list的实例
change_all(i)  # 再次调用自己

change_all(that_list)
print(that_list)

[1, 5, [9999, 4, 3, 5, [9999, 8, [88, 9999, 2], 3, 5], 2, 6], 9999, [3, 6, 9999, [9999, 2], 3], 8]


## 字典¶

1. 存储的信息量越来越多,有的时候找一个数据可能要循环整个列表,耗时较长。

2. 单个元素包含的信息量变多时,比如,之前只是存储姓名列表,现在是要存 储姓名、年龄、身份证号、地址、工作等这个人的很多信息,用列表去存储 很费劲

3. 要求存储的数据是不重复,我们知道列表是允许的重复值的,当然想存储时 就让我的数据默认就是唯一的话,用列表就不可以了

1. key-value 格式,key 是唯一的

2. 无序,与列表有序的特点不同,字典是无序的,列表之所以有序是因为你需要通过索引来定位相应元素,而字典已经可以通过 key 来定位相应 value,因 此为了避免浪费存储空间,字典不会对数据的位置进行纪录,当然如果你想 让其变成有序的,也是有方法的,这个我们以后再讲。

3. 查询速度很快, dict是基于hash表的原理实现的, 是根据关键字(Key／value) 而直接访问在内存存储位置的数据结构。也就是说,它通过把键值通过一个 函数的计算,映射到表中一个位置来访问记录,这加快了查找速度。这个映 射函数称做散列函数,存放记录的数组称做散列表。由于通过一个 key 的索 引表就直接定位到了内存地址,所以查询一个只有 100 条数据的字典和一个 100 万条数据的字典的速度是查不多的。

In [54]:
# 创建字典, Key/Value 格式

user_profiles = {
"name": "Kevin",
"age": 12,
"job": "IT"
}
print(user_profiles)
print(user_profiles['name'])
print(user_profiles['age'])
print(user_profiles['job'])

{'age': 12, 'job': 'IT', 'name': 'Kevin'}
Kevin
12
IT


In [ ]:
class dict(object):
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list.  For example:  dict(one=1, two=2)
"""

def clear(self): # real signature unknown; restored from __doc__
""" 清除内容 """
""" D.clear() -> None.  Remove all items from D. """
pass

def copy(self): # real signature unknown; restored from __doc__
""" 浅拷贝 """
""" D.copy() -> a shallow copy of D """
pass

@staticmethod # known case
def fromkeys(S, v=None): # real signature unknown; restored from __doc__
"""
dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
v defaults to None.
"""
pass

def get(self, k, d=None): # real signature unknown; restored from __doc__
""" 根据key获取值，d是默认值 """
""" D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None. """
pass

def has_key(self, k): # real signature unknown; restored from __doc__
""" 是否有key """
""" D.has_key(k) -> True if D has a key k, else False """
return False

def items(self): # real signature unknown; restored from __doc__
""" 所有项的列表形式 """
""" D.items() -> list of D's (key, value) pairs, as 2-tuples """
return []

def iteritems(self): # real signature unknown; restored from __doc__
""" 项可迭代 """
""" D.iteritems() -> an iterator over the (key, value) items of D """
pass

def iterkeys(self): # real signature unknown; restored from __doc__
""" key可迭代 """
""" D.iterkeys() -> an iterator over the keys of D """
pass

def itervalues(self): # real signature unknown; restored from __doc__
""" value可迭代 """
""" D.itervalues() -> an iterator over the values of D """
pass

def keys(self): # real signature unknown; restored from __doc__
""" 所有的key列表 """
""" D.keys() -> list of D's keys """
return []

def pop(self, k, d=None): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
If key is not found, d is returned if given, otherwise KeyError is raised
"""
pass

def popitem(self): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.popitem() -> (k, v), remove and return some (key, value) pair as a
2-tuple; but raise KeyError if D is empty.
"""
pass

def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
""" 如果key不存在，则创建，如果存在，则返回已存在的值且不修改 """
""" D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
pass

def update(self, E=None, **F): # known special case of dict.update
""" 更新
{'name':'alex', 'age': 18000}
[('name','sbsbsb'),]
"""
"""
D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
In either case, this is followed by: for k in F: D[k] = F[k]
"""
pass

def values(self): # real signature unknown; restored from __doc__
""" 所有的值 """
""" D.values() -> list of D's values """
return []

def viewitems(self): # real signature unknown; restored from __doc__
""" 所有项，只是将内容保存至view对象中 """
""" D.viewitems() -> a set-like object providing a view on D's items """
pass

def viewkeys(self): # real signature unknown; restored from __doc__
""" D.viewkeys() -> a set-like object providing a view on D's keys """
pass

def viewvalues(self): # real signature unknown; restored from __doc__
""" D.viewvalues() -> an object providing a view on D's values """
pass

def __cmp__(self, y): # real signature unknown; restored from __doc__
""" x.__cmp__(y) <==> cmp(x,y) """
pass

def __contains__(self, k): # real signature unknown; restored from __doc__
""" D.__contains__(k) -> True if D has a key k, else False """
return False

def __delitem__(self, y): # real signature unknown; restored from __doc__
""" x.__delitem__(y) <==> del x[y] """
pass

def __eq__(self, y): # real signature unknown; restored from __doc__
""" x.__eq__(y) <==> x==y """
pass

def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass

def __getitem__(self, y): # real signature unknown; restored from __doc__
""" x.__getitem__(y) <==> x[y] """
pass

def __ge__(self, y): # real signature unknown; restored from __doc__
""" x.__ge__(y) <==> x>=y """
pass

def __gt__(self, y): # real signature unknown; restored from __doc__
""" x.__gt__(y) <==> x>y """
pass

def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list.  For example:  dict(one=1, two=2)
# (copied from class doc)
"""
pass

def __iter__(self): # real signature unknown; restored from __doc__
""" x.__iter__() <==> iter(x) """
pass

def __len__(self): # real signature unknown; restored from __doc__
""" x.__len__() <==> len(x) """
pass

def __le__(self, y): # real signature unknown; restored from __doc__
""" x.__le__(y) <==> x<=y """
pass

def __lt__(self, y): # real signature unknown; restored from __doc__
""" x.__lt__(y) <==> x<y """
pass

@staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass

def __ne__(self, y): # real signature unknown; restored from __doc__
""" x.__ne__(y) <==> x!=y """
pass

def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass

def __setitem__(self, i, y): # real signature unknown; restored from __doc__
""" x.__setitem__(i, y) <==> x[i]=y """
pass

def __sizeof__(self): # real signature unknown; restored from __doc__
""" D.__sizeof__() -> size of D in memory, in bytes """
pass

__hash__ = None

dict

In [55]:
# 使用key，修改value
user_profiles['name'] = 'Liangxiansen'  # 修改name对应的value,如果name不存在就会创建一个这样得对应值
print(user_profiles)

{'age': 12, 'job': 'IT', 'name': 'Liangxiansen'}

In [56]:
# 字典的pop方法删除指定一条数据
user_profiles.pop('name')  # 删除'name'这条数据
print(user_profiles)

Out[56]:
'Liangxiansen'
{'age': 12, 'job': 'IT'}

In [57]:
# 字典的popitem方法会随机删除一条字典得数据(尽量不要使用)
user_profiles.popitem()  # 随机删除一条数据,dict为空得时候会报错
print(user_profiles)

Out[57]:
('age', 12)
{'job': 'IT'}

In [58]:
# 字典的items方法可以将字典的key,value以字典视图的形式返回（尽量不要使用，大字典的时候，你没发确认有多大数据）
user_info = {
"name": "lianglian",
"age": 12,
"job": "IT"
}

new_user_info = list(user_info.items())  # 将dict的key,value转换成列表字典视图形式的list，再通过list函数转换成真正可操作的list
print(new_user_info)

[('age', 12), ('job', 'IT'), ('name', 'lianglian')]

In [117]:
# 字典的values方法可以将字典的value以字典视图形式返回(大字典得时候,谨慎使用，你没法确认下面嵌套字典有多大数据)
new_user_info = list(user_info.values())  # 将dict的key,value转换成字典视图形式的list，再通过list函数转换成真正可操作的list
print(new_user_info)

['lianglian', 'IT', 12]

In [59]:
# 字典的keys方法可以将字典的key以字典视图的形式返回(相对上面两种推荐使用这种,通过key去取value)
print(user_info.keys())  # 将dict的key转换成字典视图形式的list，再通过list函数转换成真正可操作的list
print(list(user_info.keys())) # 使用list函数变成列表。

dict_keys(['age', 'job', 'name'])
['age', 'job', 'name']

In [60]:
# 字典的get方法安全的去查询一个key得value,不存在得key不会报错

print(user_info.get('na'))  # 查找一个key,如果存在则返回value,如果不存在不会报错,返回None
print(user_info.get('name'))

None
lianglian

In [61]:
# 字典的setdefault方法可以安全得去修改一个key得值,这个key存在不会覆盖掉

print(user_info.setdefault('name','Test'))
print(user_info)
# 找一个key为'name'的记录,如果这个key不存在,那就创建一个叫'name'的key,
# 并且将其value设置为'Test',如果这个key存在,就直接返回这个key的value

lianglian
{'age': 12, 'job': 'IT', 'name': 'lianglian'}

In [62]:
# 通过字典的update方法拿一个新的字典去更新一个旧的字典

test_dict = {
'age': 18,
'name': 'liang',
}

user_info.update(test_dict)
print(user_info)

{'age': 18, 'job': 'IT', 'address': 'BeiJing', 'name': 'liang'}

In [63]:
# 字典的clear方法清除字典全部内容,保留字典类型

test_dict.clear()  # 清空dict
print(test_dict)

{}

In [64]:
# 字典的copy方法copy属于浅copy
profiles_info = {
"name": "lianglian",
"age": 12,
"job": "IT",
"hobby": {
"book": "三国演义",
"movement": "skateboard"
}
}

new_profiles_info = profiles_info.copy()
print(profiles_info)
print(new_profiles_info)

profiles_info['age'] = 16
profiles_info['hobby']['book'] = '三体'
print(profiles_info)
print(new_profiles_info)

{'age': 12, 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三国演义'}, 'name': 'lianglian'}
{'age': 12, 'name': 'lianglian', 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三国演义'}}
{'age': 16, 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三体'}, 'name': 'lianglian'}
{'age': 12, 'name': 'lianglian', 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三体'}}


In [65]:
# 字典的copy模块的deepcopy方法实现深copy
import copy
profiles_info = {
"name": "lianglian",
"age": 12,
"job": "IT",
"hobby": {
"book": "三国演义",
"movement": "skateboard"
}
}

new_profiles_info = copy.deepcopy(profiles_info)
print(profiles_info)
print(new_profiles_info)

profiles_info['age'] = 16
profiles_info['hobby']['book'] = '三体'
print(profiles_info)
print(new_profiles_info)

{'age': 12, 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三国演义'}, 'name': 'lianglian'}
{'age': 12, 'name': 'lianglian', 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三国演义'}}
{'age': 16, 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三体'}, 'name': 'lianglian'}
{'age': 12, 'name': 'lianglian', 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三国演义'}}

In [66]:
# 遍历字典

print(profiles_info)

for key in profiles_info:
value = profiles_info[key]
print(key, value)

{'age': 16, 'job': 'IT', 'hobby': {'movement': 'skateboard', 'book': '三体'}, 'name': 'lianglian'}
age 16
job IT
hobby {'movement': 'skateboard', 'book': '三体'}
name lianglian


## 集合¶

python 的 集合（set） 和其他语言类似, 是一个无序 不重复 元素集, 基本功能包括关系测 适合消除重复元素. 集合对象还支持 union(联合), intersection(交), difference(差)sysmmetric difference(对称差集)等数学运算.

set 支持 x in set, len(set),和 for x in set。作为一个无序的集合,set 不记录元素位置或者插入点。因此,set 不支持 indexing, slicing, 或其它类序列 (sequence-like)的操作。

In [67]:
# 通过set关键字函数来创建集合
s = set('hello')
l = list('hello')
print(s)
print(l)

{'e', 'o', 'l', 'h'}
['h', 'e', 'l', 'l', 'o']


In [68]:
t = set('world')

s.union(t)    #  s 和 t 的并集（两个合并到一块）
print(s | t)

print(s.intersection(t))  # s 和 t的交集(取出两个都有的)
print(s & t)

print(s.difference(t))  # 求差集(项在s中,但是不在t中)
print(s - t)

print(s.symmetric_difference(t)) # 对称差集(两个中不相同的)
print(s ^ t)

Out[68]:
{'d', 'e', 'h', 'l', 'o', 'r', 'w'}
{'h', 'e', 'w', 'o', 'd', 'r', 'l'}
{'o', 'l'}
{'o', 'l'}
{'e', 'h'}
{'e', 'h'}
{'e', 'w', 'd', 'r', 'h'}
{'e', 'w', 'd', 'r', 'h'}

In [69]:
# 集合add方法添加新元素
s
print(s)

Out[69]:
{'e', 'h', 'l', 'o'}
{'e', 'o', 'l', 'u', 'h'}

In [70]:
# 集合update方法添加多个元素，可以接受迭代的对象，循环add，批量添加

t = set("Hello")
print(t)

t1 = set("Hello")
t1.update("world")
print(t1)

{'world', 'e', 'o', 'H', 'l'}
{'H', 'e', 'w', 'o', 'd', 'r', 'l'}

In [71]:
# 差集更新（在s中有的,在t中没有更新到s）
s = set("Hello")
t = set("World")

print(s)
s.difference_update(t)
print(s)

{'e', 'o', 'H', 'l'}
{'H', 'e'}

In [72]:
# 集合remove方法,移除指定值,如果没有会报错
s = set("Hello")
s.remove("H")
print(s)

{'e', 'o', 'l'}

In [73]:
# 集合discard方法,移除指定值,如果没有不会报错
s = set("Hello")
print(s)

{'e', 'o', 'H', 'l'}

In [74]:
old_dict = {
"#1": 8,
"#2": 4,
"#4": 2,
}

new_dict = {
"#1": 4,
"#2": 4,
"#3": 2,
}

# old_dict 中没有, new_dict 中有的加到 old_dict
old_set = set(old_dict.keys())
new_set = set(new_dict.keys())

remove_set = old_set.difference(new_set)
update_set = old_set.intersection(new_set)


删除:{'#4'}



## 内存指针¶

In [20]:
name1 = 'liangxiansen'
name2 = 'Kevin'

print(name1)
print(name2)

print('name1 内存地址：', id(name1))
print('name2 内存地址：', id(name2))

liangxiansen
Kevin
name1 内存地址： 4350694512
name2 内存地址： 4322625272


In [22]:
name3 = name1

print(name1)
print(name3)

print('name1 内存地址：', id(name1))
print('name3 内存地址：', id(name3))

liangxiansen
liangxiansen
name1 内存地址： 4350694512
name3 内存地址： 4350694512