Howto? neatly compare pandas columns at different indices

Part 1 (2018)
1

There’s lots related to this on Stackoverflow etc, but I’m struggling with a neat and efficient code to put it together. I’m new to pandas/python - I’m sure people here can improve this. As in the subject I just want to compare columns that should be identical but shifted in indexes. Neat but error throwing code:

ishift=24*60 
len(df[df["col1"][:-ishift]!=df["col2"][ishift:]])

returns #ValueError: Can only compare identically-labeled Series objects
because

print(df[“col1”][:-ishift].index , df[“col2”][ishift:].index

RangeIndex(start=0, stop=28560, step=1) RangeIndex(start=1440, stop=30000, step=1)

I’ve messed around with copies, and resetting indexes etc , but this (working example) is really ugly to me

a=df["col2"][180:]
a=a.reset_index(drop=True)
b=df["col1"][:-180]
print(len(b), len(b!=a))
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