pandas.errors.ParserWarning¶
-
exception
pandas.errors.
ParserWarning
[source]¶ Warning raised when reading a file that doesn’t use the default ‘c’ parser.
Raised by pd.read_csv and pd.read_table when it is necessary to change parsers, generally from the default ‘c’ parser to ‘python’.
It happens due to a lack of support or functionality for parsing a particular attribute of a CSV file with the requested engine.
Currently, ‘c’ unsupported options include the following parameters:
- sep other than a single character (e.g. regex separators)
- skipfooter higher than 0
- sep=None with delim_whitespace=False
The warning can be avoided by adding engine=’python’ as a parameter in pd.read_csv and pd.read_table methods.
See also
pd.read_csv
- Read CSV (comma-separated) file into DataFrame.
pd.read_table
- Read general delimited file into DataFrame.
Examples
Using a sep in pd.read_csv other than a single character:
>>> import io >>> csv = u'''a;b;c ... 1;1,8 ... 1;2,1''' >>> df = pd.read_csv(io.StringIO(csv), sep='[;,]') ... # ParserWarning: Falling back to the 'python' engine...
Adding engine=’python’ to pd.read_csv removes the Warning:
>>> df = pd.read_csv(io.StringIO(csv), sep='[;,]', engine='python')