python - 向量化函数 (Python)

Question

我是 python 的新手，正在尝试进行硬件分配，但它一直向我抛出此错误(在 iPython Notebook 中):

"TypeError: unsupported operand type(s) for ** or pow(): 'list' and 'float'"

这是我试图模仿的公式:h(x)=(1/√2π)*e^−(1/2)^x^2

import numpy as np
import math
from math import *


def h_scalar(x):
    return (1 / sqrt(2 * pi)) * exp(-.50** x ** 2.00)

我正在努力取得与我的老师相同的成绩。

l = [-10.0, -1.0, 0.0, 1.0, 10.0] #
print h_scalar(l)
>>> [1.4867195147342977e-06, 0.24197072451914337, 0.3989422804014327,
0.24197072451914337, 1.4867195147342977e-06]

顺便问一下老师的问题:

First of all, write a function called h_scalar. The function should expect a list (or in general an item that is iterable). It will expect that the list contains floating point values. It should return a new list of floats that are the h(x) for each x value in the input list. You should name your function h_scalar()

Answer 1

使用 numpy 的 sqrt 和 exp 将获得更好的性能，它们将按元素运行:

import numpy as np
from numpy import sqrt, exp, pi
def h_scalar(x):
    x = np.array(x)
    return (1/sqrt(2*pi)) * exp(-0.50*x**2)

你可以像这样使用它:

x = [-10.0, -1.0, 0.0, 1.0, 10.0]
h_scalar(x)