将带有NaNs的Numpy数组写入python中的CSV中 [英] Writing Numpy Array with NaNs into CSV in python

问题描述

我正在尝试使用np.savetxt将2D numpy array写入csv文件.

I am trying to write 2D numpy array into csv file using np.savetxt.

import numpy as np

data = np.array([[0,np.nan,2,3],[4,5,np.nan,7],[8,9,10,np.nan]])

np.savetxt("file.csv", data, delimiter=",", fmt='%.2f')

将创建具有以下内容的文件file.csv.

Which creates a file file.csv with the following content.

0.00,nan,2.00,3.00
4.00,5.00,nan,7.00
8.00,9.00,10.00,nan

如您所见，该文件包含nan而不是空白.我知道nan不是字符串.

As you can see the file contains nan instead of blanks. I know nan is not a string.

预期输出:

0.00,,2.00,3.00
4.00,5.00,,7.00
8.00,9.00,10.00,

使用pandas我可以像下面这样实现.

Using pandas I can achieve this like below.

import pandas as pd

df = pd.DataFrame(data)
df.to_csv("file1.csv", index=False)

但是我暂时不使用pandas.那么可以使用numpy做到这一点吗?

But I'm refraining from using pandas for now. So is it possible to achieve this using numpy?

推荐答案

最直接的解决方案:

data1 = data.astype(str)
data1[data1=='nan'] = ''
np.savetxt("file.csv", data1, delimiter=",", fmt="%s")

这篇关于将带有NaNs的Numpy数组写入python中的CSV中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！