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偏函数
您可以通过使用functools库中的partial函数在Python中创建偏函数。
偏函数允许将具有x个参数的函数派生为具有更少参数的函数，并为更有限的函数设置固定值。
需要导入：
from functools import partial
这段代码将返回8。
from functools import partial
def multiply(x, y):
return x * y
# 创建一个新的乘以2的函数
dbl = partial(multiply, 2)
print(dbl(4))
一个重要的注意事项：默认值将从左开始替换变量。2将替换x。当调用dbl(4)时，y将等于4。在这个例子中没有区别，但在下面的例子中有区别。
练习
通过调用partial()并替换func()中的前三个变量来编辑提供的函数。然后仅用一个输入变量使用新的偏函数打印，以使输出等于60。
#Following is the exercise, function provided:
from functools import partial
def func(u, v, w, x):
return u*4 + v*3 + w*2 + x
#Enter your code here to create and print with your partial function
from functools import partial
def func(u, v, w, x):
return u*4 + v*3 + w*2 + x
p = partial(func,5,6,7)
print(p(8))
#test_object('p')
test_output_contains('60')
success_msg('Good job!')
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