derive_var_obs_number: Adds a Variable Numbering the Observations Within Each By...

In epijim/admiral: ADaM in R Asset Library

Description

Adds a variable numbering the observations within each by group

Usage

derive_var_obs_number(
  dataset,
  by_vars = NULL,
  order = NULL,
  new_var = ASEQ,
  check_type = "none"
)

Arguments

dataset	Input dataset The variables specified by the order and the by_vars parameter are expected.
by_vars	Grouping variables Permitted Values: list of variables
order	Sort order Within each by group the observations are ordered by the specified order. Permitted Values: list of variables or functions of variables
new_var	Name of variable to create The new variable is set to the observation number for each by group. The numbering starts with 1. Default: ASEQ
check_type	Check uniqueness? If "warning" or "error" is specified, the specified message is issued if the observations of the input dataset are not unique with respect to the by variables and the order. Default: "none" Permitted Values: "none", "warning", "error"

Details

For each group (with respect to the variables specified for the by_vars parameter) the first or last observation (with respect to the order specified for the order parameter and the mode specified for the mode parameter) is included in the output dataset.

Value

A dataset containing all observations and variables of the input dataset and additionally the variable specified by the new_var parameter.

Author(s)

Stefan Bundfuss

Examples

library(dplyr, warn.conflicts = FALSE)
library(admiral.test)
data("vs")

vs %>%
  select(USUBJID, VSTESTCD, VISITNUM, VSTPTNUM) %>%
  filter(VSTESTCD %in% c("HEIGHT", "WEIGHT")) %>%
  derive_var_obs_number(
    by_vars = vars(USUBJID, VSTESTCD),
    order = vars(VISITNUM, VSTPTNUM)
  )

epijim/admiral documentation built on Feb. 13, 2022, 12:15 a.m.