Stacked: stack columns from a wide form to a long form
Usage
Stacked(data, id.vars, var.stubs, sep, keep.all = TRUE,
...)Arguments
data
The source data.frame.
id.vars
The variables that serve as unique
identifiers.
var.stubs
The prefixes of the variable groups.
sep
The character that separates the "variable
name" from the "times" in the wide data.frame.
keep.all
Logical. Should all the variables from
the source data.frame be kept (keep.all =
TRUE) or should the resulting
data.table comprise
only columns for ...
Further arguments to NoSep in
case the separator is of a different form. Value
- A
list of data.tables with one
data.table for each "var.stub". The
key is set to the
id.vars and .time_#} vars.
A function to conveniently stack groups of wide columns
into a long form which can then be
merged together.
This is the function internally called by
merged.stack.
set.seed(1)
mydf <- data.frame(id_1 = 1:6, id_2 = c("A", "B"),
varA.1 = sample(letters, 6),
varA.2 = sample(letters, 6),
varA.3 = sample(letters, 6),
varB.2 = sample(10, 6),
varB.3 = sample(10, 6),
varC.3 = rnorm(6))
mydf
Stacked(data = mydf, id.vars = c("id_1", "id_2"),
var.stubs = c("varA", "varB", "varC"),
sep = "\\.")rm(mydf)
[object Object],[object Object]
stack, melt
from "reshape2".