[Python笔记]第二篇:运算符、基本数据类型
本篇主要内容有：运算符 基本数据类型等
一、运算符
1、算术运算
2、比较运算
3、赋值运算
4、逻辑运算
5、成员运算
6、身份运算
7、位运算
8、运算符优先级
二、基本数据类型
１.整数：int
在32位机器上，整数的位数为32位，取值范围为-2**31～2**31-1，即-2147483648～2147483647
在64位系统上，整数的位数为64位，取值范围为-2**63～2**63-1，即-9223372036854775808～9223372036854775807
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 def __add__(self, y):
""" x.__add__(y) <==> x+y """
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 def __radd__(self, y):
""" x.__radd__(y) <==> y+x """
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
int
２.字符串：str
例如"hello world"
字符串常用功能：
- 移除空白（strip）
- 分割（split）
- 长度（len）
- 索引（index）
- 切片（str_name[0:len(str_name)）
- 拼接（join）
- 替换（replace）
- 转大写（upper）
- 翻转大小写（swapcase）
- 查包含的方法（dir）
- 字符串拼接（+或者(str1.__add__(str2))）
- 首字母大写（capitalize）
- 字符串居中，其他位置填充星号（center(长度,"*")）
- 统计字符串出现次数（count）
- 判断以某字符开头（startswith）
- 判断以某字符结尾（endswith）
- Tab符转换为空格（expandtabs）
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，返回 -1 """
"""
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，报错 """
S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found.
"""
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 """
"""
S.partition(sep) -> (head, sep, tail) 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 Like S.rfind() but raise ValueError when the substring is not found.
"""
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):
"""
S.rpartition(sep) -> (head, sep, tail) 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
separator is not found, return two empty strings and S.
"""
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 Return a titlecased version of S, i.e. words start with uppercase
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 = ""
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 def __add__(self, y):
""" x.__add__(y) <==> x+y """
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
str
str
３.列表：list
例如[11,22,33,44]
列表基本操作：
- 索引（index）
- 切片（[xx_index:xx_index]）
- 追加（append）
- 删除（del或者pop或者remove...）
- 长度（len）
- 循环（while或者for）
- 包含（in）
- 翻转（reverse）
class list(object):
"""
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
"""
def append(self, p_object): # real signature unknown; restored from __doc__
""" L.append(object) -- append object to end """
pass def count(self, value): # real signature unknown; restored from __doc__
""" L.count(value) -> integer -- return number of occurrences of value """
return 0 def extend(self, iterable): # real signature unknown; restored from __doc__
""" L.extend(iterable) -- extend list by appending elements from the iterable """
pass def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
L.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
return 0 def insert(self, index, p_object): # real signature unknown; restored from __doc__
""" L.insert(index, object) -- insert object before index """
pass def pop(self, index=None): # real signature unknown; restored from __doc__
"""
L.pop([index]) -> item -- remove and return item at index (default last).
Raises IndexError if list is empty or index is out of range.
"""
pass def remove(self, value): # real signature unknown; restored from __doc__
"""
L.remove(value) -- remove first occurrence of value.
Raises ValueError if the value is not present.
"""
pass def reverse(self): # real signature unknown; restored from __doc__
""" L.reverse() -- reverse *IN PLACE* """
pass def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__
"""
L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
cmp(x, y) -> -1, 0, 1
"""
pass def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y): # real signature unknown; restored from __doc__
""" x.__contains__(y) <==> y in x """
pass def __delitem__(self, y): # real signature unknown; restored from __doc__
""" x.__delitem__(y) <==> del x[y] """
pass def __delslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__delslice__(i, j) <==> del x[i:j] Use of negative indices is not supported.
"""
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 __getslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
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 __iadd__(self, y): # real signature unknown; restored from __doc__
""" x.__iadd__(y) <==> x+=y """
pass def __imul__(self, y): # real signature unknown; restored from __doc__
""" x.__imul__(y) <==> x*=y """
pass def __init__(self, seq=()): # known special case of list.__init__
"""
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
# (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 def __mul__(self, n): # real signature unknown; restored from __doc__
""" x.__mul__(n) <==> x*n """
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 __reversed__(self): # real signature unknown; restored from __doc__
""" L.__reversed__() -- return a reverse iterator over the list """
pass def __rmul__(self, n): # real signature unknown; restored from __doc__
""" x.__rmul__(n) <==> n*x """
pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__
""" x.__setitem__(i, y) <==> x[i]=y """
pass def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__
"""
x.__setslice__(i, j, y) <==> x[i:j]=y Use of negative indices is not supported.
"""
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" L.__sizeof__() -- size of L in memory, in bytes """
pass __hash__ = None
list
list
列表内删除元素举例：
#del删除对应下标的元素
>>> li = [11,22,33,44,55,66]
>>> del li[1]
>>> li
[11, 33, 44, 55, 66] #pop.()删除最后一个元素
>>> li.pop()
>>> li
[11, 33, 44, 55] #删除指定元素
>>> li.remove(33)
>>> li
[11, 44, 55] #使用切片删除
>>> li = li[:-1]
>>> li
[11, 44]
列表删除用法举例
４.元祖：tuple
基本操作：
- 索引（index）
- 切片（1：3）
- 循环(for)
- 长度(len)
- 包含(in)
#索引指定下标位置的元素
print(name_tuple[0]) #len 判断元组长度
print(len(name_tuple)) #切片操作
print(name_tuple[0:1]) #for循环操作
for i in name_tuple:
print(i) # count，计算元素出现的个数
print(name_tuple.count('seven')) # index 获取指定元素的索引位置
print(name_tuple.index('seven)) #删除
不支持类似列表的删除操作del name_tuple[0]
元组用法举例
class tuple(object):
"""
tuple() -> empty tuple
tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object.
"""
def count(self, value): # real signature unknown; restored from __doc__
""" T.count(value) -> integer -- return number of occurrences of value """
return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
T.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
return 0 def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y): # real signature unknown; restored from __doc__
""" x.__contains__(y) <==> y in x """
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 __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
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 __hash__(self): # real signature unknown; restored from __doc__
""" x.__hash__() <==> hash(x) """
pass def __init__(self, seq=()): # known special case of tuple.__init__
"""
tuple() -> empty tuple
tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object.
# (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 def __mul__(self, n): # real signature unknown; restored from __doc__
""" x.__mul__(n) <==> x*n """
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 __rmul__(self, n): # real signature unknown; restored from __doc__
""" x.__rmul__(n) <==> n*x """
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" T.__sizeof__() -- size of T in memory, in bytes """
pass
tuple
tuple
５.字典：dict
常用操作：
- 索引（index）
- 新增（update）
- 删除（del）
- 清空（clear）
- 键、值、键值对（）
- 循环（while或者for）
- 长度（len）
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
dict
字典用法举例：
#!/usr/bin/env python
#-*- coding: utf-8 -*- ###################### 字典 ###################
user_info = {
"name": "Jerry",
"age": 100,
"geder": 'Male'
} '''
字典的每一个元素，称为键值对：
0 “Jerry"
1 100
''' # 根据key获取对应value
print(user_info["name"])
print(user_info["age"]) for i in user_info:
print(i) # 循环，默认值输出key
print(user_info.keys()) # 获取所有键
print(user_info.values()) # 获取所有值
print(user_info.items()) # 获取所有键值对 #循环所有keys和values的另一种方式
for i in user_info.keys():
print(i)
for i in user_info.values():
print(i) user_info.clear() # clear，清除所有内容 # get 根据key获取值，如果key不存在，可以指定一个默认值
val = user_info.get('age')
print(val)
val = user_info.get('age', '')
print(val) # 索引取值时，key不存在，报错
print(user_info['age'])
print(user_info['age1111']) # has_key 检查字典中指定key是否存在
print(user_info.has_key("name")) #in判断包含某个元素
ret = 'agfffe' in user_info.keys()
print(ret) # pop删除最尾部的一个元素
user_info.pop() # update 添加元素
print(user_info)
test = {
"a1": 123,
'a2': 456
}
user_info.update(test)
print(user_info) ##############################
# 删除指定索引的键值对
test = {
"a1": 123,
'a2': 456
} del test['a1']
print(test) # enumerate自动生成一列，默认0 自增一
li = ["电脑", "鼠标垫", "U盘", '游艇']
for key, item in enumerate(li, 1):
print(key,item) # 没有采用enumerate自动生成之前
li = ["电脑", "鼠标垫", "U盘", '游艇']
for item in li:
print(item)
#
inp = input("请输入商品:") inp = input("请输入商品:")
# 字符串转换成int
inp_num = int(inp)
#
# inp = "0"
# li[inp] li['0'] 错 li[0]
print(li[inp_num-1]) li = ["电脑", "鼠标垫", "U盘", '游艇'] inp = input("请输入内容：")
ret = li.index(inp)
print(ret) # range,xrange
# py2.7
# range，用获取指定范围内的数，range(0,10000000)
# xrange，用获取指定范围内的数，xrange(0,10000000)
for i in xrange(1, 1000):
print(i) py3，range，等同2.7xrange
print(range(1,10))
for i in range(1,10, 2):
print(i) print(range(10,1))
for i in range(10,1, -2):
print(i) li = ['alex', 'eirc'] leee = len(li) # for i in range(0, leee):
print(i,li[i])
字典用法举例
6.set集合
set集合，是一个无序且不重复的元素集合
#!/usr/bin/env python
#-*- coding: utf-8 -*- class set(object):
"""
set() -> new empty set object
set(iterable) -> new set object Build an unordered collection of unique elements.
"""
def add(self, *args, **kwargs): # real signature unknown
"""
Add an element to a set，添加元素 This has no effect if the element is already present.
"""
pass def clear(self, *args, **kwargs): # real signature unknown
""" Remove all elements from this set. 清除内容"""
pass def copy(self, *args, **kwargs): # real signature unknown
""" Return a shallow copy of a set. 浅拷贝 """
pass def difference(self, *args, **kwargs): # real signature unknown
"""
Return the difference of two or more sets as a new set.
A.difference(B)找出A中存在的和B中不存在的元素
(i.e. all elements that are in this set but not the others.)
"""
pass def difference_update(self, *args, **kwargs): # real signature unknown
""" Remove all elements of another set from this set.
A从当前集合中删除和B中相同的元素,然后更新到A自身"""
pass def discard(self, *args, **kwargs): # real signature unknown
"""
Remove an element from a set if it is a member. If the element is not a member, do nothing. 移除指定元素，元素不存在不保错
"""
pass def intersection(self, *args, **kwargs): # real signature unknown
"""
Return the intersection of two sets as a new set. 交集 (i.e. all elements that are in both sets.)
"""
pass def intersection_update(self, *args, **kwargs): # real signature unknown
""" Update a set with the intersection of itself and another. 取交集并更更新到A中 """
pass def isdisjoint(self, *args, **kwargs): # real signature unknown
""" Return True if two sets have a null intersection. 如果没有交集，返回True，否则返回False"""
pass def issubset(self, *args, **kwargs): # real signature unknown
""" Report whether another set contains this set. 判断xx是否是xx的子序列"""
pass def issuperset(self, *args, **kwargs): # real signature unknown
""" Report whether this set contains another set. 判断xx是否是xx父序列"""
pass def pop(self, *args, **kwargs): # real signature unknown
"""
Remove and return an arbitrary set element.
Raises KeyError if the set is empty. 移除元素 并返回个值
"""
pass def remove(self, *args, **kwargs): # real signature unknown
"""
Remove an element from a set; it must be a member. If the element is not a member, raise a KeyError. 移除指定元素，不存在报错
"""
pass def symmetric_difference(self, *args, **kwargs): # real signature unknown
"""
Return the symmetric difference of two sets as a new set. 对称交集 (i.e. all elements that are in exactly one of the sets.)
"""
pass def symmetric_difference_update(self, *args, **kwargs): # real signature unknown
""" Update a set with the symmetric difference of itself and another. 对称交集，并更新到a中 """
pass def union(self, *args, **kwargs): # real signature unknown
"""
Return the union of sets as a new set. 并集 (i.e. all elements that are in either set.)
"""
pass def update(self, *args, **kwargs): # real signature unknown
""" Update a set with the union of itself and others. 更新集合 """
pass
set集合
set集合的用法举例
# 添加元素
se = { 11, 22, 33}
print(se)
se.add(44)
print(se)
se.clear()
print(se) ##########################################################################################
# difference
se = {11, 22, 33}
be = {22, 55} # 找se中存在，be中不存在的集合，并将其赋值给新变量
ret = se.difference(be)
print(ret) # 找se中存在，be中不存在的集合，更新se自己
se.difference_update(be) print(se) ########################################################################################## se = {11, 22, 33, 44}
be = {11, 22, 77, 55} # 合集
ret1 = se.union(be)
print(ret1) 添加 还有add方法也是
se.update([444,555,666])
print(se) r1 = se.difference(be)
r2 = be.difference(se)
print(r1)
print(r2) # 对称交际
ret = se.symmetric_difference(be)
print(ret) # 对称交集并更新自身
se.symmetric_difference_update(be)
print(se) # 是否是子序列
ret = se.issubset(be)
print(ret) # 是否是父序列
ret = se.issuperset(be)
print(ret) # （随机）移出并返回值
ret = se.pop
print(ret) # 移出指定值，指定值找不到则报错
se.remove() # 移出指定值，指定值找不到不报错
se.discard() ##########################################################################################
三、补充内容及作业
1.查看对象的类，或对象所具备的功能
1、type
temp = "alex"
t = type(temp)
print(t)
## IDE里面 str, ctr+鼠标左，找到 str类，内部所有的方法 2、dir
temp = "alex"
b = dir(temp) 3、help，type
help(type(temp)) 4、Pycharm环境下查看
直接点击
temp = "alex"
temp.upper()
## IDE里面鼠标放在upper() 上 Ctrl+左键，自动定位到 upper功能处
2.enumrate
为可迭代的对象添加序号
li = [11,22,33]
for k,v in enumerate(li, 1): #指定从1开始显示序号
print(k,v) #执行结果
(1, 11) (2, 22) (3, 33)
3.range和xrange
指定范围，生成指定的数字
py3，range，等同2.7xrange
print range(1, 10)
# 结果：[1, 2, 3, 4, 5, 6, 7, 8, 9] print range(1, 10, 2)
# 结果：[1, 3, 5, 7, 9] print range(30, 0, -2)
# 结果：[30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2]
4.作业
1元素分类
有如下值集合 [11,22,33,44,55,66,77,88,99,90...]，将所有大于 66 的值保存至字典的第一个key中，将小于 66 的值保存至第二个key的值中。
即： {'k1': 大于66的所有值, 'k2': 小于66的所有值}
2.查找
查找列表中元素，移动空格，并查找以 a或A开头 并且以 c 结尾的所有元素。
li = ["alec", " aric", "Alex", "Tony", "rain"]
tu = ("alec", " aric", "Alex", "Tony", "rain")
dic = {'k1': "alex", 'k2': ' aric', "k3": "Alex", "k4": "Tony"}
3.输出商品列表，用户输入序号，显示用户选中的商品
商品 li = ["手机", "电脑", '鼠标垫', '游艇']
4.购物车
功能要求：
- 要求用户输入总资产，例如：2000
- 显示商品列表，让用户根据序号选择商品，加入购物车
- 购买，如果商品总额大于总资产，提示账户余额不足，否则，购买成功。
- 附加：可充值、某商品移除购物车
goods = [
{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998},
]
5.用户交互，显示省市县三级联动的选择
dic = {
"河北": {
"石家庄": ["鹿泉", "藁城", "元氏"],
"邯郸": ["永年", "涉县", "磁县"],
}
"河南": {
...
}
"山西": {
...
}
}
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