Subset rows of a data structure in order.

Subset rows of a data structure in order.

Usage

# S3 method for flowSet
slice_max(
  .data,
  order_by,
  ...,
  n,
  prop,
  by = NULL,
  with_ties = TRUE,
  na_rm = FALSE
)

Arguments

.data

A flowSet

order_by

Variable or function of variables to order by. To order by multiple variables, wrap them in a data frame or tibble.

...

Unused.

n, prop

Provide either n, the number of rows, or prop, the proportion of rows to select. If neither are supplied, n = 1 will be used. If n is greater than the number of rows in the group (or prop > 1), the result will be silently truncated to the group size. prop will be rounded towards zero to generate an integer number of rows.

A negative value of n or prop will be subtracted from the group size. For example, n = -2 with a group of 5 rows will select 5 - 2 = 3 rows; prop = -0.25 with 8 rows will select 8 * (1 - 0.25) = 6 rows.

by

Optionally, an unquoted selection of columns to group by for just this operation. An alternative to group_by.

with_ties

Should ties be kept together? The default, TRUE, may return more rows than you request. Use FALSE to ignore ties, and return the first n rows.

na_rm

Should missing values in order_by be removed from the result? If FALSE, NA values are sorted to the end so they will only be included if there are insufficient non-missing values to reach n/prop.

Value

An object of the same type as .data. The output has the following properties: * Each row may appear 0, 1, or many times in the output. * Columns are not modified. * Groups are not modified. * A flowSet's pData is preserved.

Examples

my_flowset <- simulate_cytometry_data()$flowset

my_flowset |>
  dplyr::slice_max(order_by = feature_1, n = 10)
#> A flowSet with 5 experiments.
#> 
#> column names(10): feature_1 feature_2 ... feature_9 feature_10
#>