在字典中阅读时“没有要从文件中解析的列”

Question

I'm trying to take a dictionary object in python, write it out to a csv file, and then read it back in from that csv file.

But it's not working. When I try to read it back in, it gives me the following error:

EmptyDataError: No columns to parse from file

I don't understand this for two reasons. Firstly, if I used pandas very own to_csv method, it should be giving me the correct format for a csv. Secondly, when I print out the header values (by doing this: print(df.columns.values) ) of the dataframe that I'm trying to save, it says I do in fact have headers ("one" and "two".) So if the object I was sending out had column names, I don't know why they wouldn't be found when I'm trying to read it back.

import pandas as pd
testing = {"one":1,"two":2 }
df = pd.DataFrame(testing, index=[0])

file = open('testing.csv','w')

df.to_csv(file)

new_df = pd.read_csv("testing.csv")

What am I doing wrong?

Thanks in advance for the help!

Answer 1

The default pandas.DataFrame.to_csv takes a path and not an text io . Just remove the file declaration and directly use the path, pass index = False to skip indexes.

import pandas as pd
testing = {"one":1,"two":2 }
df = pd.DataFrame(testing, index=[0])

df.to_csv('testing.csv', index = False)

new_df = pd.read_csv("testing.csv")