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csvpandasmergeglob

Horizontal append in for loop?

I have a for loop iterating over a folder of one column csv's using glob, it makes some adjustments and then appends the results to a list and saves to a new csv, it resembles:

data= []
infiles = glob.glob("*.csv")
for file in infiles:
    df = pd.io.parsers.read_csv(file)
    (assorted adjustments)
    data.append(df)
fullpanel = pd.concat(panel)
fullpanel.to_csv('data.csv')

The problem is that makes one long column, I need each column (of differing lengths) added next to each other.

Solution

  • I think you can add parameter axis=1 to concat for columns added next to each other. Also you can change pd.io.parsers.read_csv to pd.read_csv and panel to data in concat.

    data= []
infiles = glob.glob("*.csv")
for file in infiles:
    df = pd.read_csv(file)
    (assorted adjustments)
    data.append(df)
fullpanel = pd.concat(data, axis=1)
fullpanel.to_csv('data.csv')