clinpubr (version 1.3.0)

to_wide: Fast long-to-wide conversion with item selection

Description

Convert long-format data to wide format by grouping keys, using one column as item names and one column as values. When there are multiple values under the same key-item combination, values are reduced by agg_fun. Designed to convert long-format clinical data in database to wide format for analysis and publication.

Usage

to_wide(df, keys, item_col, value_col, items = NULL, agg_fun = get_valid)

Value

A wide-format data frame.

Arguments

df

A data frame in long format.

keys

A character vector of key column names.

item_col

A single column name that contains item names.

value_col

A single column name that contains values to spread.

items

Optional character vector of items to keep in wide format. If provided, output item columns follow this order and missing items are kept as NA columns.

agg_fun

Aggregation function used when key-item combinations have multiple values. Default is get_valid().

Examples

df <- data.frame(
  id = c(1, 1, 1, 2, 2),
  visit = c("v1", "v1", "v1", "v1", "v1"),
  item = c("A", "A", "B", "A", "C"),
  value = c(3, 5, 2, 1, 9)
)

to_wide(
  df,
  keys = c("id", "visit"),
  item_col = "item",
  value_col = "value",
  items = c("A", "B", "C"),
  agg_fun = max
)