Get pandas.read_csv to read empty values as empty string instead of nan

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I"m using the pandas library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can"t figure out how to get it not to read an empty value as NaN. Here"s sample data and output

One,Two,Three
a,1,one
b,2,two
,3,three
d,4,nan
e,5,five
nan,6,
g,7,seven

>>> pandas.read_csv("test.csv", na_values={"One": [], "Three": []})
    One  Two  Three
0    a    1    one
1    b    2    two
2  NaN    3  three
3    d    4    nan
4    e    5   five
5  nan    6    NaN
6    g    7  seven

It correctly reads "nan" as the string "nan", but still reads the empty cells as NaN. I tried passing in str in the converters argument to read_csv (with converters={"One": str})), but it still reads the empty cells as NaN.

I realize I can fill the values after reading, with fillna, but is there really no way to tell pandas that an empty cell in a particular CSV column should be read as an empty string instead of NaN?

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Walter Porretti

London | 2023-02-04

I was preparing for my coding interview, thanks for clarifying this - Get pandas.read_csv to read empty values as empty string instead of nan in Python is not the simplest one. Checked yesterday, it works!

Oliver Emmerson

Warsaw | 2023-02-04

I was preparing for my coding interview, thanks for clarifying this - Get pandas.read_csv to read empty values as empty string instead of nan in Python is not the simplest one. I am just not quite sure it is the best method

Jan Sikorski

Abu Dhabi | 2023-02-04

Ev PHP module is always a bit confusing 😭 Get pandas.read_csv to read empty values as empty string instead of nan is not the only problem I encountered. I am just not quite sure it is the best method

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