将浮点数的字符串containsg数组转换为numpy数组 [英] Convert string containg array of floats to numpy array

问题描述

我有一个浮点数数组，希望将其转换为通过JSON传输的字符串:

I have a numpy array of floats that I wish to convert to a string to transmit via JSON:

import numpy as np
#Create an array of float arrays
numbers = np.array([[1.0, 2.0],[3.0,4.0],[5.0,6.0]], dtype=np.float64)
print(numbers)
[[1. 2.]
 [3. 4.]
 [5. 6.]]

#Convert each row in the array to string and separate by a ','
numbers_to_string_commas = ','.join(str(number) for number in numbers)
print(numbers_to_string_commas)
[1. 2.],[3. 4.],[5. 6.]

现在，我希望将此字符串转换回原始的numpy数组.我尝试使用以下方法，但没有任何乐趣:

Now I wish to convert this string back into the original numpy array. I have tried using the following but I have had no joy:

a = np.fromstring(numbers_to_string_commas, dtype=np.float64, sep=',')
print(a)
[]

我该怎么做?

推荐答案

我认为问题在于格式不完全是

I think the problem is that the format is not quite the formats that numpy is expecting, but if the string is not too huge:

In [39]: eval('np.array([%s])' % '[1. 2.],[3. 4.],[5. 6.]'.replace(' ', ','))
Out[39]: 
array([[1., 2.],
       [3., 4.],
       [5., 6.]])

请注意，如果字符串很长，您可能会遇到问题: 为什么对python的eval有长度限制?

Be aware if the string is very long you might run into issues: Why is there a length limit to python's eval?

这篇关于将浮点数的字符串containsg数组转换为numpy数组的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！