filter(function, iterable)¶Construct an iterator from those elements of iterable for which function returns true. iterable may be either a sequence, a container which supports iteration, or an iterator. If function is None, the identity function is assumed, that is, all elements of iterable that are false are removed.Note that filter(function, iterable) is equivalent to the generator expression (item for item in iterable if function(item)) if function is not None and (item for item in iterable if item) if function is None.See itertools.filterfalse() for the complementary function that returns elements of iterable for which function returns false.nie 

filter说明

map(function, iterable, ...)
Return an iterator that applies function to every item of iterable, yielding the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel. With multiple iterables, the iterator stops when the shortest iterable is exhausted. For cases where the function inputs are already arranged into argument tuples, see itertools.starmap().

map说明

>>> li = [11, 22, 33]
>>> new_list = map(lambda a: a + 100, li)
>>> for n in new_list: print(n)111
122
133

>>> new_list = map(lambda a: a + 100, li)
>>> zyl = list(new_list)
>>> zyl
[111, 122, 133]

>>> zyl = map(str, range(5))
>>> for i in zyl: print(i)

0
1
2
3
4
>>> zyl01 = map(add, range(5))
>>> for i in zyl01: print(i)

0
2
4
6
8
>>> zyl02 = map(lambda x: x+1, range(5))
>>> tj = list(zyl02)
>>> tj
[1, 2, 3, 4, 5]
>>> zyl03 = map(add, 'zhayilig')
>>> tj01 = list(zyl03)
>>> tj01
['zz', 'hh', 'aa', 'yy', 'ii', 'll', 'ii', 'gg']

>>> def add(x,y):return x+y

>>> zyl04 = map(add, 'zhagyiligon','lovepython')
>>> tj02 = list(zyl04)
>>> tj02
['zl', 'ho', 'av', 'ge', 'yp', 'iy', 'lt', 'ih', 'go', 'on']
>>> zyl05= map(add, 'zhagyilig','python')
>>> tj03 = list(zyl05)
>>> tj03
['zp', 'hy', 'at', 'gh', 'yo', 'in']

>>> li = [11, 22, 33]
>>> new_list = filter(lambda a: a > 20, li)
>>> zyl = list(new_list)
>>> zyl
[22, 33]

>>> fil = filter(div, range(6))
>>> zyl = list(fil)
>>> zyl
[1, 3, 5]

>>> fil = filter(lambda x : x%2,range(10))   #lambda 函数返回奇数，返回列表
>>> zyl = list(fil)
>>> zyl
[1, 3, 5, 7, 9]

>>> fil = filter(lambda x : not x%2,range(10))
>>> zyl = list(fil)
>>> zyl
[0, 2, 4, 6, 8]

>>> def fin(n):return n!='z'  #过滤'z' 函数，出现z则返回False

>>> fil = filter(fin, 'zhgyilig') 
>>> for i in fil:print(i)

h
g
y
i
l
i
g

>>> fil = filter(lambda x: x != 'z', 'zhgyilig')  #labmda返回True值
>>> zyl = list(fil)
>>> zyl
['h', 'g', 'y', 'i', 'l', 'i', 'g']
>>> fil = filter(lambda x: x == 'z', 'zhgyilig')  #返回：字符串
>>> zyl = list(fil)
>>> zyl
['z']

#!/usr/bin/env python
# Author:zhagyiligdef is_prime(start,stop):stop = stop + 1prime = filter(lambda x: not [x%i for i in range(2,x) if x%i == 0],range(start,stop))print(list(prime))if __name__ == '__main__':try:start = int(input("enter a start number: "))except:start = int(2)try:stop = int(input("enter a stop number: "))except:start = int(0)is_prime(start,stop)

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