list comprehension in pandas

Question

I\'m giving a toy example but it will help me understand what\'s going on for something else I\'m trying to do. Let\'s say I want a new column in a dataframe \'optimal_fruit

Answer 1

The reason why your new method doesn't work is because the list comprehension produces data that is longer than the number of indices in your dataframe. A quick fix for that would be something like:

[x * y - z for x,y,z in zip(df2['apples'], df2['oranges'], df2['bananas'])]