# Aggregates in Pandas

Learn the basics of aggregate functions in Pandas, which let us calculate quantities that describe groups of data..

Start- 1
This lesson you will learn about

*aggregates*in Pandas. An*aggregate*statistic is a way of creating a single number that describes a group of numbers. Common aggregate statistics incluse mean,... - 2
In the previous lesson, you learned how to perform operations on each value in a column using [...] . In this exercise, you will learn how to

*combine*all of the values from a column for a sing... - 3
When we have a bunch of data, we often want to calculate aggregate statistics (mean, standard deviation, median, percentiles, etc.) over certain subsets of the data. Suppose we have a grade book w...

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After using [...] , we often need to clean our resulting data. As we saw in the previous exercise, the [...] function creates a new Series, not a DataFrame. For our ShoeFly.com example, the in...

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Sometimes, the operation that you want to perform is more complicated than [...] or [...] . In those cases, you can use the [...] method and lambda functions, just like we did for individual ...

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Sometimes, we want to group by more than one column. We can easily do this by passing a list of column names into the [...] method. Imagine that we run a chain of stores and have data about the...

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When we perform a [...] across multiple columns, we often want to change how our data is stored. For instance, recall the example where we are running a chain of stores and have data about the n...

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This lesson introduced you to aggregates in Pandas. You learned:

*How to perform*aggregate*statistics over individual rows with the same value using [...] .*How to rearrange a DataFrame into...

## What you'll create

Portfolio projects that showcase your new skills

## How you'll master it

Stress-test your knowledge with quizzes that help commit syntax to memory