Search code examples
pythonpandasunicodeutf-8

pandas to_csv: ascii can't encode character

I'm trying to read and write a dataframe to a pipe-delimited file. Some of the characters are non-Roman letters (`, ç, ñ, etc.). But it breaks when I try to write out the accents as ASCII.

df = pd.read_csv('filename.txt',sep='|', encoding='utf-8')
<do stuff>
newdf.to_csv('output.txt', sep='|', index=False, encoding='ascii')

-------

  File "<ipython-input-63-ae528ab37b8f>", line 21, in <module>
    newdf.to_csv(filename,sep='|',index=False, encoding='ascii')

  File "C:\Users\aliceell\AppData\Local\Continuum\Anaconda3\lib\site-packages\pandas\core\frame.py", line 1344, in to_csv
    formatter.save()

  File "C:\Users\aliceell\AppData\Local\Continuum\Anaconda3\lib\site-packages\pandas\formats\format.py", line 1551, in save
    self._save()

  File "C:\Users\aliceell\AppData\Local\Continuum\Anaconda3\lib\site-packages\pandas\formats\format.py", line 1652, in _save
    self._save_chunk(start_i, end_i)

  File "C:\Users\aliceell\AppData\Local\Continuum\Anaconda3\lib\site-packages\pandas\formats\format.py", line 1678, in _save_chunk
    lib.write_csv_rows(self.data, ix, self.nlevels, self.cols, self.writer)

  File "pandas\lib.pyx", line 1075, in pandas.lib.write_csv_rows (pandas\lib.c:19767)

UnicodeEncodeError: 'ascii' codec can't encode character '\xb4' in position 7: ordinal not in range(128)

If I change to_csv to have utf-8 encoding, then I can't read the file in properly:

newdf.to_csv('output.txt',sep='|',index=False,encoding='utf-8')
pd.read_csv('output.txt', sep='|')

> UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb4 in position 2: invalid start byte

My goal is to have a pipe-delimited file that retains the accents and special characters.

Also, is there an easy way to figure out which line read_csv is breaking on? Right now I don't know how to get it to show me the bad character(s).

Solution

  • You have some characters that are not ASCII and therefore cannot be encoded as you are trying to do. I would just use utf-8 as suggested in a comment.

    To check which lines are causing the issue you can try something like this:

    def is_not_ascii(string):
    return string is not None and any([ord(s) >= 128 for s in string])

df[df[col].apply(is_not_ascii)]

    You'll need to specify the column col you are testing.