How to use variables inside query in Pandas?

Question

I have problem quering the data frame in panda when I use variable instead of value.

df2 = pd.read_csv('my.csv')
query=df2.query('cc_vehicle_line==7')

works fine but

df2 = pd.read_csv('my.csv')
query=df2.query('cc_vehicle_line==variable_name')

It throws the message that variable_name is undefined.But it is defined. I cannot use hardcoded value as I need to automate and depending of value of variable_name, select relevant rows.

Am I missing something?

Thanks

Asked By: user437777

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Source

Answer 1

You should use @variable_name with @

query=df2.query('cc_vehicle_line==@variable_name')

Answered By: Zero

Answer 2

You can also use ->

query=df2.query(f’cc_vehicle_line=="{variable_name}"’)
query=df2.query(f"cc_vehicle_line=='{variable_name}’")
query=df2.query(‘cc_vehicle_line==@variable_name’)
query=df2.query("cc_vehicle_line== {0}".format(variable_name))

Answered By: ylnhari

How to use variables inside query in Pandas?

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