summarise.dtplyr_step {dtplyr}R Documentation

Summarise each group to one row

Description

This is a method for the dplyr summarise() generic. It is translated to the j argument of [.data.table.

Usage

## S3 method for class 'dtplyr_step'
summarise(.data, ...)

Arguments

.data

A lazy_dt().

...

<data-masking> Name-value pairs of summary functions. The name will be the name of the variable in the result.

The value can be:

  • A vector of length 1, e.g. min(x), n(), or sum(is.na(y)).

  • A vector of length n, e.g. quantile().

  • A data frame, to add multiple columns from a single expression.

Examples

library(dplyr, warn.conflicts = FALSE)

dt <- lazy_dt(mtcars)

dt %>%
  group_by(cyl) %>%
  summarise(vs = mean(vs))

dt %>%
  group_by(cyl) %>%
  summarise(across(disp:wt, mean))

[Package dtplyr version 1.1.0 Index]