Pandas Dataframe - Sort Multiple Column Values with Custom Key

This Pandas Dataframe tutorial shows you how to sort multiple column values with a custom key.

Suppose you have the following data:

And you want to sort on the Level and Reviews column and you need to define the custom key for the level column. Below is an example:

ranking_level_sort = {
    "Exceptional": 5,
    "Excellent": 4,
    "Very good": 3,
    "Good": 2,
    "Review score": 1,
    "None": 0
}

Pandas Dataframe - Sort Mulitple Column Values with Custom Key Example

You can use the map for both columns, so in reviews no matching and returned NaN, so need to replace them with original values using fillna. Below is an example:

hotel_sorted = hotel.sort_values(by=["level", "reviews"],  
                                 key=lambda x: x.map(ranking_level_sort).fillna(x), 
                                 ascending=False)
hotel_sorted.reset_index(drop=True, inplace=True)

print (hotel_sorted)

Output:

See also:

• Python Program to Sort Objects Without Comparison
• ValueError: grouper and axis must be same length