The Python Oracle

Pandas: Check if column value is smaller than any previous column value

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Chapters
00:00 Pandas: Check If Column Value Is Smaller Than Any Previous Column Value
00:34 Accepted Answer Score 9
00:47 Thank you

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Full question
https://stackoverflow.com/questions/5373...

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Tags
#python #pandas

#avk47


ACCEPTED ANSWER

Score 9


This should work:

df['diff'] = df['c'] < df['c'].cummax()

Output is just as you mentioned:

    c   diff
0   1  False
1   4  False
2   9  False
3   7   True
4   8   True
5  36  False