How to sum a variable by group

How to sum a variable by group

r dataframe aggregate r-faq

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Mean per group in a data.frame [duplicate]

r aggregate

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Aggregate / summarize multiple variables per group (e.g. sum, mean)

r dataframe data.table aggregate r-faq

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Summarizing multiple columns with dplyr? [duplicate]

r dplyr aggregate

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Count number of rows within each group

r dataframe aggregate r-faq

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Apply several summary functions on several variables by group in one call

r aggregate r-faq

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Collapse / concatenate / aggregate a column to a single comma separated string within each group

r aggregate r-faq

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Extract row corresponding to minimum value of a variable by group

r dplyr data.table aggregate

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Extract the maximum value within each group in a dataframe [duplicate]

r aggregate

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Add count of unique / distinct values by group to the original data

r count unique aggregate

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data.frame Group By column [duplicate]

r aggregate

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Name columns within aggregate in R

r rename aggregate

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Select the top N values by group

r aggregate

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Aggregating by unique identifier and concatenating related values into a string [duplicate]

r concatenation aggregate

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Count number of rows per group and add result to original data frame

r count aggregate r-faq

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