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Count Number of Observations Where a Variable Equals a Value

Source: R/filter_joined.R
count_vals.Rd

Count number of observations where a variable equals a value.

Usage

count_vals(var, val)

Arguments

var

A vector

val

A value

See also

Utilities for Filtering Observations: filter_exist(), filter_extreme(), filter_joined(), filter_not_exist(), filter_relative(), max_cond(), min_cond()

Examples


library(tibble)
library(dplyr, warn.conflicts = FALSE)
library(admiral)
data <- tribble(
  ~USUBJID, ~AVISITN, ~AVALC,
  "1",      1,        "PR",
  "1",      2,        "CR",
  "1",      3,        "NE",
  "1",      4,        "CR",
  "1",      5,        "NE",
  "2",      1,        "CR",
  "2",      2,        "PR",
  "2",      3,        "CR",
  "3",      1,        "CR",
  "4",      1,        "CR",
  "4",      2,        "NE",
  "4",      3,        "NE",
  "4",      4,        "CR",
  "4",      5,        "PR"
)

# add variable providing the number of NEs for each subject
group_by(data, USUBJID) %>%
  mutate(nr_nes = count_vals(var = AVALC, val = "NE"))
#> # A tibble: 14 × 4
#> # Groups:   USUBJID [4]
#>    USUBJID AVISITN AVALC nr_nes
#>    <chr>     <dbl> <chr>  <int>
#>  1 1             1 PR         2
#>  2 1             2 CR         2
#>  3 1             3 NE         2
#>  4 1             4 CR         2
#>  5 1             5 NE         2
#>  6 2             1 CR         0
#>  7 2             2 PR         0
#>  8 2             3 CR         0
#>  9 3             1 CR         0
#> 10 4             1 CR         2
#> 11 4             2 NE         2
#> 12 4             3 NE         2
#> 13 4             4 CR         2
#> 14 4             5 PR         2