Display thousand values with a comma separator in polars

pl.Config.set_thousands_separator

It’s easier to read large numerical values when they’re separated by a comma every three digits. For instance, your brain can more easily comprehend 5,000,000 at a glance than 5000000. Polars allows you to format numerical values with commas to improve readability. Below is a dataframe showing department budgets for a company:

shape: (5, 2)

Department	Budget
str	i64
"Hospitality"	5700000
"Legal"	1200000
"Finance"	8300000
"Advertising"	6800000
"Sales"	9200000

Insert commas in values

We can make the budget values more human-readable by separating each group of three digits with a comma. Here’s how to do it:

with pl.Config(thousands_separator=','):
    display(df)

shape: (5, 2)

Department	Budget
str	i64
"Hospitality"	5,700,000
"Legal"	1,200,000
"Finance"	8,300,000
"Advertising"	6,800,000
"Sales"	9,200,000

If you live in Brazil (where the thousand separator is a full stop), you can replace , with .

with pl.Config(thousands_separator='.'):
    display(df)

shape: (5, 2)

Department	Budget
str	i64
"Hospitality"	5.700.000
"Legal"	1.200.000
"Finance"	8.300.000
"Advertising"	6.800.000
"Sales"	9.200.000

Tip

You can configure this setting globally so that all your dataframes use the same configuration. All you need to do is have these two lines at the beginning of your Python script.

import polars as pl
pl.Config(thousands_separator=',')

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