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pythonpandaslambda

Using Two Variables In Lambda Python

I want to make a new column based on two variables. I want my new column to have the value "Good" if (column 1 >= .5 or column 2 < 0.5) and (column 1 < .5 or column 2 >= 0.5) otherwise "Bad".

I tried using lambda and if. 

df["new column"] = df[["column 1", "column 2"]].apply(
    lambda x, y: "Good" if (x >= 0.5 or y < 0.5) and (x < 0.5 or y >= 0.5) else "Bad"
)

Got

TypeError: ("() missing 1 required positional argument: 'y'", 'occurred at index column 1')
Solution

  • Try this:

    import pandas as pd 

def update_column(row):
    if (row['x'] >= .5 or row['y'] <= .5) and (row['x'] < .5 or row['y'] >= .5):
        return "Good"
    return "Bad"

df['new_column'] = df.apply(update_column, axis=1)