内置函数
abs() divmod() input() open() staticmethod() all() enumerate() int() ord() str() any() eval() isinstance() pow() sum() basestring() execfile() issubclass() print() super() bin() file() iter() property() tuple() bool() filter() len() range() type() bytearray() float() list() raw_input() unichr() callable() format() locals() reduce() unicode() chr() frozenset() long() reload() vars() classmethod() getattr() map() repr() xrange() cmp() globals() max() reverse() zip() compile() hasattr() memoryview() round() __import__() complex() hash() min() set() delattr() help() next() setattr() dict() hex() object() slice() dir() id() oct() sorted() exec 内置表达式
all()
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
print(all([1,2,'123']))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
True
Process finished with exit code 0
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
print(all([1,2,'123','']))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
False
Process finished with exit code 0
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
print(all('123 556'))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
True
Process finished with exit code 0
eval()
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
print(eval('1+3*2'))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
7
Process finished with exit code 0
filter(): 过滤器
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
str = ['a','b','c','d']
def fun1(s):
if s != 'a':
return s
ret = filter(fun1,str)
print(ret)
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
<filter object at 0x7fce389d6820>
Process finished with exit code 0
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
str = ['a','b','c','d']
def fun1(s):
if s != 'a':
return s
ret = filter(fun1,str)
print(list(ret)) #ret是一个迭代器对象
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
['b', 'c', 'd']
Process finished with exit code 0
对sequence中的item依次执行function(item)，将执行结果为True的item做成一个filter object的迭代器返回。可以看作是过滤函数
map()
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
str = ['d','a','b']
def fun2(s):
return s + "alvin"
ret = map(fun2,str)
print(ret) # map object的迭代器
print(list(ret))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
<map object at 0x7f8468338820>
['dalvin', 'aalvin', 'balvin']
Process finished with exit code 0
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
str = ['d','a','b']
def fun2(s):
return s + "alvin"
ret = filter(fun2,str) #注意filter和map的区别
print(ret)
print(list(ret))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
<filter object at 0x7f6325d3c820>
['d', 'a', 'b']
Process finished with exit code 0
reduce()
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
from functools import reduce
def add1(x,y):
return x + y
print(reduce(add1,range(1,101))) #从1-100叠加
print(reduce(add1,range(1,101),20)) #从1-100叠加再加20
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
5050
5070
Process finished with exit code 0
对sequence中的item顺序迭代调用function，如果starting_value，还可以作为初始值调用
lambda
普通函数与匿名函数对比：
普通函数
#!/usr/bin/env python3.8
# __author: "smoke"
# date: 2021/1/10 下午7:07
def add(a,b):
return a + b
print(add(3,4))
/home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py
7
Process finished with exit code 0
匿名函数
#!/usr/bin/env python3.8 # __author: "smoke" # date: 2021/1/10 下午7:07 add = lambda a,b : a + b print(add(2,3)) /home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py 5 Process finished with exit code 0 #!/usr/bin/env python3.8 # __author: "smoke" # date: 2021/1/10 下午7:07 from functools import reduce print(reduce(lambda x,y:x * y,range(1,6))) #阶乘 /home/smoke/PycharmProjects/pythonProject/venv/bin/python /home/smoke/PycharmProjects/pythonProject/lean_python/built-in-funcation.py 120 Process finished with exit code 0
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