python学习-day16：函数作用域、匿名函数、函数式编程、map、filter、reduce函数、内置函数r

f=lambda x:x*x
print(f)           #打印指向该函数的内存地址
print(f(5))       #内存地址（5） 调用运行该函数

def cala(x):
    y=x*x
    return y
z=cala(5)
print(z)
>>>
<function <lambda> at 0x10137d950>
25
100

#name=alex  #修改为:name=alex_sb
f=lambda x:x+‘_sb‘
print(f(‘alex‘))

f=lambda x,y,z=10:x+y+z  #可以存在默认数值
print(f(3,3))
>>>>
16

f=lambda x,y,z=10:(x+1,y+1,z+1)  #如果需要对函数进行返回多个值，需要加括号
print(f(3,3))
>>>
(4, 4, 11)

#这段代码
def calc(n):
    return n**n
print(calc(10))
 
#换成匿名函数
calc = lambda n:n**n
print(calc(10))

def pf(x):
    return x**2

def add_one(x):
    return x+1

def reduce_one(x):
    return x-1

def num_pin(fanfa,array):
    new_num=[]
    for i in array:
        new_num.append(fanfa(i))
    return new_num
new_num=num_pin(pf,num_1)
print(new_num)
new_num2=num_pin(add_one,num_1)
print(new_num2)

[1, 4, 100, 25, 9, 49]
[2, 3, 11, 6, 4, 8]

num=[13,46,5,46,5,7]
def pf(x):
    return x*x

def jisuan(fuan,array):
    new_num=[]
    for i in array:
        new_num.append(fuan(i))
    return new_num

print(jisuan(pf,num))
f=lambda x:x*x
print(f)
print(lambda x:x*x)
print(jisuan(f,num))
print(jisuan(lambda x:x*x,num))
>>>>
[169, 2116, 25, 2116, 25, 49]
<function <lambda> at 0x101b7da60>
<function <lambda> at 0x101b7dae8>
[169, 2116, 25, 2116, 25, 49]
[169, 2116, 25, 2116, 25, 49]

#终极版本
def map_test(func,array): #func=lambda x:x+1    arrary=[1,2,10,5,3,7]
    ret=[]
    for i in array:
        res=func(i) #add_one(i)
        ret.append(res)
    return ret

print(map_test(lambda x:x+1,num_l))
res=map(lambda x:x+1,num_l)
print(‘内置函数map，处理结果‘,res)
# for i in res:
#     print(i)
print(list(res))
print(‘传的是有名函数‘,list(map(reduce_one,num_l)))


msg=‘linhaifeng‘
print(list(map(lambda x:x.upper(),msg)))

>>>
[2, 3, 11, 6, 4, 8]
内置函数map，处理结果 <map object at 0x101b862e8>
[2, 3, 11, 6, 4, 8]
传的是有名函数 [0, 1, 9, 4, 2, 6]
[‘L‘, ‘I‘, ‘N‘, ‘H‘, ‘A‘, ‘I‘, ‘F‘, ‘E‘, ‘N‘, ‘G‘]

①、print(list(map(lambda x:x**2,num)))

②、

num=[13,46,5,46,5,7]
def pf(x):
    return x*x
print(list(map(pf,num)))