count: Count observations by group

In tidySingleCellExperiment: Brings SingleCellExperiment to the Tidyverse

Description

'count()' lets you quickly count the unique values of one or more variables: 'df 'df 'count()' is paired with 'tally()', a lower-level helper that is equivalent to 'df switching the summary from 'n=n()' to 'n=sum(wt)'.

'add_count()' are 'add_tally()' are equivalents to 'count()' and 'tally()' but use 'mutate()' instead of 'summarise()' so that they add a new column with group-wise counts.

Usage

count(
  x,
  ...,
  wt = NULL,
  sort = FALSE,
  name = NULL,
  .drop = group_by_drop_default(x)
)

Arguments

x	A data frame, data frame extension (e.g. a tibble), or a lazy data frame (e.g. from dbplyr or dtplyr).
...	<['data-masking'][dplyr_data_masking]> Variables to group by.
wt	<['data-masking'][dplyr_data_masking]> Frequency weights. Can be 'NULL' or a variable: * If 'NULL' (the default), counts the number of rows in each group. * If a variable, computes 'sum(wt)' for each group.
sort	If 'TRUE', will show the largest groups at the top.
name	The name of the new column in the output. If omitted, it will default to ‘n'. If there’s already a column called 'n', it will error, and require you to specify the name.
.drop	For 'count()': if 'FALSE' will include counts for empty groups (i.e. for levels of factors that don't exist in the data). Deprecated in ‘add_count()' since it didn’t actually affect the output.

Value

An object of the same type as '.data'. 'count()' and 'add_count()' group transiently, so the output has the same groups as the input.

Examples

`%>%` <- magrittr::`%>%`
pbmc_small %>%
    tidy() %>%
    count(groups)

tidySingleCellExperiment documentation built on Nov. 8, 2020, 6:54 p.m.