Iterate over rows and calculate mean of selected items putting the new value in a new column

Question

Using Pandas I have a data frame with rows and columns:

id  column1 column2 column3
1         4  Banana       2
2         4  Carrot       
3         1  Tomato       3
4         7   Melon       5
5         1    Lime       5

I want to iterate through each row and calculate the mean the items in column1 and column2 (e.g. Row 1: 4+2/2=3). Everything will be put in a new column called mean. empty values should be ignored.

The result should be like:

id  column1 column2 column3  mean
1         4  Banana       2     3
2         4  Carrot             4
3         1  Tomato       3     2
4         7   Melon       5     6
5         2    Lime       5   3.5

Use `df['mean'] = df.mean(axis=1)` – jezrael Apr 06 '20 at 09:50 — jezrael, Apr 06 '20 at 09:50

score 1 · Accepted Answer · answered Apr 06 '20 at 09:46

1

You can use:

df['mean'] = df[['column1', 'column3']].mean(axis=1)

answered Apr 06 '20 at 09:46

Carsten

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just a suggestion... ```select dtypes``` could help avoid the hardcoding of the column names – sammywemmy Apr 06 '20 at 09:48
1

@sammywemmy - For me pandas omit non numeric columns, so working `df['mean'] = df.mean(axis=1)` – jezrael Apr 06 '20 at 09:50
nice. even better. – sammywemmy Apr 06 '20 at 09:51

Iterate over rows and calculate mean of selected items putting the new value in a new column

1 Answers1