Build a column based on another

Question

I am trying to build a column that will be based off of another. The new column should reflect the values meeting certain criteria and put 0's where the values do not meet the criteria.

Example, a column called bank balance will have negative and positive values; the new column, overdraft, will have the negative values for the appropriate row and 0 where the balance is greater than 0.

 Bal  Ovr
 21   0
-34 -34
 45   0
-32 -32

The final result should look like that.

`df['Ovr'] = df['Bal'].clip(upper=0)`. – Quang Hoang Dec 03 '20 at 19:27 — Quang Hoang, Dec 03 '20 at 19:27

score 1 · Accepted Answer · answered Dec 03 '20 at 19:27

1

Assuming your dataframe is called df, you can use np.where and do:

import numpy as np
df['Ovr'] = np.where(df['Bal'] <0,'df['Bal'],0)

which will create a column called Ovr, with 0's when Bal is +ve, and the same as Bal when Bal is -ve.

answered Dec 03 '20 at 19:27

sophocles

13,593
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score 1 · Answer 2 · answered Dec 03 '20 at 19:33

1

df["over"] = df.Bal.apply(lambda x: 0 if x>0 else x)

Additional method to enrich your coding skills. However, it isn't needed for such easy tasks.

answered Dec 03 '20 at 19:33

ombk

2,036
1
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Build a column based on another

2 Answers2