Use function to create a new column in a DataFrame based on DataFrame variables with pandas

Question

Have a function to assign a hex color variable based on a scale from 0-1.

In one column I have pageviews that are being assigned a scale:

df1['pvScale'] = df1['GA Page Views']/max(df1['GA Page Views'])

But when I go to create another column and have that be based off a function for assigning hex values:

df1['hex'] = colorscale("#00ff4c", df1['pvScale']) #(orginal hex, 0-1)

Getting this return:

"ValueError: The truth value of a Series is ambiguous."

What's the correct syntax to perform this operation?

Dimgold · Accepted Answer · 2017-07-04 15:48:28Z

1

Try using df.apply():

df1['hex'] = df['pvScale'].apply(lambda x: colorscale("#00ff4c", x))

It will apply the colorscale function on the values in one-by-one.

answered Jul 4, 2017 at 15:06

Dimgold

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1 Comment

Thank you! I was trying to use .apply but didn't have the lambda function.