python基础1
注：部分内容摘自：http://www.cnblogs.com/wupeiqi/articles/4911365.html。
一、整数
如：12， 45， 23
1.def bit_length(self):
""" 返回表示该数字的时占用的最少位数 """
>>>(12).bit-length()
4
>>>bin(12)
'0b1100'
2.def __abs__(self):
""" 返回绝对值 """
""" x.__abs__() <==> abs(x) """
pass
3.def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass
4.def __and__(self, y):
""" x.__and__(y) <==> x&y """
pass #在二进制位取与运算
5.def __coerce__(self, y):
""" 强制生成一个元组 """
""" x.__coerce__(y) <==> coerce(x, y) """
pass
6.def __divmod__(self, y):
""" 相除，得到商和余数组成的元组 """
""" x.__divmod__(y) <==> divmod(x, y) """
pass
7.def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass
8.def __float__(self):
""" 转换为浮点类型 """
""" x.__float__() <==> float(x) """
pass
9. def __int__(self):
""" 转换为整数 """
""" x.__int__() <==> int(x) """
pass
10. def __long__(self):
""" 转换为长整数 """
""" x.__long__() <==> long(x) """
pass
二：长整型
1.def bit_length(self): # real signature unknown; restored from __doc__
"""
long.bit_length() -> int or long
Number of bits necessary to represent self in binary.
>>> bin(37L)
'0b100101'
>>> (37L).bit_length()
6
三：浮点型
四：字符串
s = 'spam'
1.find #查到的话，返回字符的偏移量，没有查到的话，返回-1
>>>s.find(p)
1
2.replace
>>>s.replace('pa','XXX')
'sXXXm'
3.分割
>>>line = 'aa,bb,cc,dd'
lin.split(,) #括号内指定分隔符，为空则为空格。
['aa','bb','cc','dd']
4. 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')
"""
5.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 ""
6.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
7.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
8.def isalpha(self):
""" 是否是字母 """
9.def isdigit(self):
""" 是否是数字 """
10.def islower(self):
""" 是否小写 """
11. def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
12.def swapcase(self):
""" 大写变小写，小写变大写 """
"""
需求帮助：
>>>dir(line)
>>>help
五：列表
1. 追加
def append(self, p_object):
""" L.append(object) -- append object to end """
pass
2.计数
def count(self, value):
""" L.count(value) -> integer -- return number of occurrences of value """
return 0
3.扩展
def extend(self, iterable):
""" L.extend(iterable) -- extend list by appending elements from the iterable """
pass
4.删除 pop（）中间没有值的话删除最后一个并返回值
def pop(self, index=None):
"""
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
5.删除指定元素
def remove(self, value):
"""
L.remove(value) -- remove first occurrence of value.
Raises ValueError if the value is not present.
"""
pass
6.反转
def reverse(self):
""" L.reverse() -- reverse *IN PLACE* """
pass
7.排序
def sort(self, cmp=None, key=None, reverse=False):
"""
L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
cmp(x, y) -> -1, 0, 1
"""
pass
8.插入
def insert(self, index, p_object):
""" L.insert(index, object) -- insert object before index """
pass
9.def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass
10.包含
def __contains__(self, y):
""" x.__contains__(y) <==> y in x """
pass
11.判断长度
def __len__(self):
""" x.__len__() <==> len(x) """
pass
六：字典
1.def clear(self):
""" 清除内容 """
""" D.clear() -> None. Remove all items from D. """
pass
2.def copy(self):
""" 浅拷贝 """
""" D.copy() -> a shallow copy of D """
pass
3.def get(self, k, d=None):
""" 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
4.def has_key(self, k):
""" 是否有key """
""" D.has_key(k) -> True if D has a key k, else False """
return False
5.def keys(self):
""" 所有的key列表 """
""" D.keys() -> list of D's keys """
return []
6.def pop(self, k, d=None):
""" 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
"""
7.def popitem(self):
""" 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.
"""
8.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
9.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
