How to change column value by matching row value in data frame?

Say I do have the following table

longitude	latitude	temperature	label
x	y	z	1
p	q	r	2
a	b	c	1
k	l	m	1

I store the table in df and run the following data fragment query.

df1= df.query('longitude == @x and latitude == @y and temperature== @z')

Mostly I am getting the correct output.

Now I want to change the label value for my row matched by the query

df.query('longitude == a and latitude == b and temperature== c')

How can I update the label value matched by the query row. I tried using .replace , .iloc but None of them is giving me proper result.

https://stackoverflow.com/questions/66811330/how-to-change-column-value-by-matching-row-value-in-data-frame March 26, 2021 at 01:06PM