numpy.frompyfunc(func，nin，nout)函数允许创建一个任意的Python函数作为Numpy ufunc(通用函数)。
参数：
func: [A python function object ] An arbitrary python function
nin:[int] Number of input arguments to that function.
nout:[int] Number of objects returned by that function.返回： A Numpy universal function object.
例如，abs_value = numpy.frompyfunc(abs，1，1)将创建一个ufunc，该ufunc将返回数组元素的绝对值。
代码1：
# Python code to demonstrate the
# use of numpy.frompyfunc
import numpy as np
# create an array of numners
a = np.array([34, 67, 89, 15, 33, 27])
# python str function as ufunc
string_generator = np.frompyfunc(str, 1, 1)
print("Original array-", a)
print("After conversion to string-", string_generator(a))
输出：
Original array- [34 67 89 15 33 27] After conversion to string- ['34' '67' '89' '15' '33' '27']
代码2：
# Python code to demonstrate
# user-defined function as ufunc
import numpy as np
# create an array of numbers
a = np.array([345, 122, 454, 232, 334, 56, 66])
# user-defined function to check
# whether a no. is palindrome or not
def fun(x):
s = str(x)
return s[::-1]== s
# 'check_palindrome' as universal function
check_palindrome = np.frompyfunc(fun, 1, 1)
print("Original array-", a)
print("Checking of number as palindrome-",
check_palindrome(a))
输出：
Original array- [345 122 454 232 334 56 66] Checking of number as palindrome- [False False True True False False True]
注意：此自定义ufunc使用frompyfunc 始终接受ndarray作为输入参数，并返回ndarray对象作为输出。
相关用法
注：本文由纯净天空筛选整理自Tanvi_Garg大神的英文原创作品 numpy.frompyfunc() in Python。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。