collapse_dt: Collapse redundant rows of a df using the Simplify function
In dkrozelle/toolboxR: Collection of functions and scripts for bioinformatics.

Description Usage Arguments Value Examples

This function performs similar to aggregate.data.frame, but with several conveniences. This version also improves on the previous CollapseDF by temporarily coercing into a data.table structure, making it handle Big Data much better. For simplicity it currently only allows grouping by columns that exist in df by explicit column name. Collapse columns are moved to the front of the df.

1	collapse_dt(df, column.names, unique = F)

`df`	DataFrame containing column.names
`column.names`	character vector of column names used for grouping rows. Performs a similar function as "by=" in aggregate()

collapsed data.table. This can be used as a data.frame or returned as dt

df <- data.frame(
  Patient = c(1,   1,  2,  2,  3,  4),
  Age     = c(31, 31, 32, NA, 33, NA),
  Score   = c( 9, 10,  8,  8, "",  4))
collapse_dt(df, "Patient")
 #   Patient   Age   Score
 # 1       1    31   10; 9
 # 2       2    32       8
 # 3       3    33
 # 4       4    NA       4