Using lambda if condition on different columns in Pandas dataframe
Solution
use a vectorized approach
frame['d'] = frame.b + (frame.c > 0) * (frame.c - frame.b)Explanation
This is derived from the sum of
(frame.c > 0) * frame.c # frame.c if positivePlus
(frame.c <= 0) * frame.b # frame.b if c is not positiveHowever
(frame.c <=0 )is equivalent to
(1 - frame.c > 0)and when combined you get
frame['d'] = frame.b + (frame.c > 0) * (frame.c - frame.b)