Pandas
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Applying a function to multiple columns in groupsCalculating percentiles of a DataFrameCalculating the percentage of each value in each groupComputing descriptive statistics of each groupDifference between a group's count and sizeDifference between methods apply and transform for groupbyGetting cumulative sum of each groupGetting descriptive statistics of DataFrameGetting multiple aggregates of a column after groupingGetting n rows with smallest column value in each groupGetting number of distinct rows in each groupGetting size of each groupGetting specific group after groupbyGetting the first row of each groupGetting the last row of each groupGetting the top n rows with largest column value in each groupGetting unique values of each groupGrouping by multiple columnsGrouping without turning group column into indexMerging rows within a group togetherNaming columns after aggregationSorting values within groups
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Getting size of each group in Pandas
schedule Aug 12, 2023
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Tags Python●Pandas
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To get the size of each group in Pandas, use the groups' size() method.
Example
Consider the following DataFrame about some products:
df = pd.DataFrame({"price":[500,300,700, 200,900], "brand":["apple", "google", "apple", "google","apple"], "device":["phone","phone","computer","phone","phone"]}, index=["a","b","c","d","e"])df
price brand devicea 500 apple phoneb 300 google phonec 700 apple computerd 200 google phonee 900 apple phone
To get the number of products offered by each brand:
df.groupby("brand").size() # returns a Series
brandapple 3google 2dtype: int64
Published by Isshin Inada
Edited by 0 others
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