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pythonpandasnumpycsvdelimiter

Trailing delimiter confuses pandas read_csv

A csv (comma delimited) file, where lines have an extra trailing delimiter, seems to confuse pandas.read_csv. (The data file is [1])

It treats the extra delimiter as if there's an extra column. So there's one more column than what headers require. Then pandas.read_csv takes the first column as row labels. The overall effect is that columns and headers are not aligned any more - the first column becomes row labels, the second column is named by first header, etc.

It is quite annoying. Any idea how to tell pandas.read_csv do the right thing? I couldn't find one.

Great book, BTW.

[1]: 2012 FEC Election Database from chapter 9 of the book Python for Data Analysis

Solution

  • I created a GitHub issue to have a look at handling this issue automatically:

    https://github.com/pydata/pandas/issues/2442

    I think the FEC file format changed slightly causing this annoying issue-- if you use the one posted here http://github.com/pydata/pydata-book you hopefully won't have that problem.