How to create a New Column in Pandas on if else condition in Python

Question

This is my dataframe. I want to create a new column named mpg_high

The condition of the column is: mpg_high = 1 if mpg > average mpg (this is the mean of mpg where I placed np.mean(df.mpg) else = 0.

I tried various methods but kept getting syntax errors. How can I do this?

Thanks in advance

Andrej Kesely · Accepted Answer · 2021-04-21 17:57:56Z

1

You can use np.where:

df['mpg_high'] = np.where(df.mpg > np.mean(df.mpg), 1, 0)

answered Apr 21, 2021 at 17:57

Andrej Kesely

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Comments

Rob Raymond · Accepted Answer · 2021-04-21 18:00:24Z

1

It can be reduced to straight binary comparison and conversion to int

df = pd.DataFrame({"mgp":np.random.randint(15,35, 50)})

df["mgp_high"] = df["mgp"].gt(df["mgp"].mean()).astype(int)

answered Apr 21, 2021 at 18:00

Rob Raymond

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