Two text files, want to add a column value

[deanhystad]

If it is guaranteed that the two files will contain the same timestamps you can do this:

import pandas as pd
import io

f1 = io.StringIO("""
20220617 14:30:00, 1.1
20220617 14:40:00, 1.3
20220617 14:50:00, 1.7
20220617 15:00:00, 1.4
""")

f2 = io.StringIO("""
20220617 14:30:00, 2.1
20220617 14:40:00, 2.3
20220617 14:50:00, 2.7
20220617 15:00:00, 2.4
""")

df1 = pd.read_csv(f1, names=("Date", "Value"))
df2 = pd.read_csv(f2, names=("Date", "Value"))

print(df1)
print(df2)
print(df1 + df2)

Output:
                Date  Value
0  20220617 14:30:00    1.1
1  20220617 14:40:00    1.3
2  20220617 14:50:00    1.7
3  20220617 15:00:00    1.4
                Date  Value
0  20220617 14:30:00    2.1
1  20220617 14:40:00    2.3
2  20220617 14:50:00    2.7
3  20220617 15:00:00    2.4
                                 Date  Value
0  20220617 14:30:0020220617 14:30:00    3.2
1  20220617 14:40:0020220617 14:40:00    3.6
2  20220617 14:50:0020220617 14:50:00    4.4
3  20220617 15:00:0020220617 15:00:00    3.8

Instead of printing you would (df1 + df2).write_csv(file_path)