count: Count observations by group

In tidyft: Fast and Memory Efficient Data Operations in Tidy Syntax

Count observations by group

Description

Analogous function for count and add_count in dplyr.

Usage

count(.data, ..., sort = FALSE, name = "n")

add_count(.data, ..., name = "n")

Arguments

.data	data.table
...	variables to group by.
sort	logical. If TRUE result will be sorted in desending order by resulting variable.
name	character. Name of resulting variable. Default uses "n".

Value

data.table

Examples

a = as.data.table(mtcars)
count(a,cyl)
count(a,cyl,sort = TRUE)
a

b = as.data.table(iris)
b %>% add_count(Species,name = "N")
b

tidyft documentation built on Sept. 30, 2024, 9:40 a.m.