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Full Version: Copying column values up based on other column values
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Hello,

I have this dataframe

import numpy as np
import pandas as pd
from numpy.random import randn
df=pd.DataFrame(randn(5,4),['A','B','C','D','E'],['W','X','Y','Z'])
Output:
W X Y Z A -0.183141 -0.398652 0.909746 0.332105 B -0.587611 -2.046930 1.446886 0.167606 C 1.142661 -0.861617 -0.180631 1.650463 D 1.174805 -0.957653 1.854577 0.335818 E -0.680611 -1.051793 1.448004 -0.490869
is there a way to create a column S - which will copy column column Y values UP- if values in column Y are above 1 - otherwise return new value above zero?.I made this manually:

Output:
S: A 1.446886 B 1.446886 C 1.854577 D 1.854577 E 1.448004
thanks a lot!
thank you - I included all the code...the last column S was manually created by me as a reference for the code required for this operation...in excel there is a quick way to back-propagate a cell value by making it equal to the next one - eg A10=A11 - is there a quick way to do that in pandas given that it operates on arrays?