csv-import – Tarik Billa

pandas read_csv and filter columns with usecols

December 19, 2022 by Tarik

The solution lies in understanding these two keyword arguments: names is only necessary when there is no header row in your file and you want to specify other arguments (such as usecols) using column names rather than integer indices. usecols is supposed to provide a filter before reading the whole DataFrame into memory; if used … Read more

Create Pandas DataFrame from a string

September 18, 2022 by Tarik

A simple way to do this is to use StringIO.StringIO (python2) or io.StringIO (python3) and pass that to the pandas.read_csv function. E.g: import sys if sys.version_info[0] < 3: from StringIO import StringIO else: from io import StringIO import pandas as pd TESTDATA = StringIO(“””col1;col2;col3 1;4.4;99 2;4.5;200 3;4.7;65 4;3.2;140 “””) df = pd.read_csv(TESTDATA, sep=”;”)