Python Pandas .loc function

Question

i have some question. I want to change one value in a column. Is there any diff in output between this two examples?

wards.loc[wards['ward'] == '1', ['ward']] = '61'

&

wards.loc[wards['ward'] == '1'] = '61'

Thanks for replies.

You can also simply do: wards['ward'] = wards['ward'].replace('1', '61') This is simpler in my opinion, but they are just about the same amount of characters, and I think a direct replace would be more performant. — David Erickson
– David Erickson, Commented Dec 5, 2020 at 10:09

avarice · Accepted Answer · 2020-12-05 10:06:58Z

1

Yes, there is difference.

The first one will select all columns of the dataframe where the criteria has matched.
And the second one will select only the ward column as a dataframe where the criteria has matched.
But if you not use [] then it will get a series.
Also these are don't different if ward is the only column in dataframe.

answered Dec 5, 2020 at 10:06

avarice

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