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pythonpandastranspose

Create a dataframe from a csv containing only rows

I have a csv file like:

feature1
feature2
feature3
f1_v1
f2_v1
f3_v1
f1_v2
f2_v2
f3_v2
...

I want to get a dataframe like this:

    feature1 feature2 feature3
0   f1_v1    f2_v1    f3_v1
1   f1_v2    f2_v2    f3_v2
...

How can I do that?

Solution

  • Read it into a list of lists and convert after. I'm not sure why so many people are afraid of preprocessing their data to allow it to fit into pandas, but that should be a common strategy.

    import pandas as pd

headers = []
rows = []

for line in open('x.csv'):
    line = line.strip()
    if len(headers) < 3:
        headers.append(line)
        continue
    if not rows or len(rows[-1]) == 3:
        rows.append([])
    rows[-1].append(line)

df = pd.DataFrame(rows, columns=headers)
print(df)

    Output:

      feature1 feature2 feature3
0    f1_v1    f2_v1    f3_v1
1    f1_v2    f2_v2    f3_v2