MultiWide2Long: A function that reshapes data from wide format to long format...

In jonathantemplin/EPSY905R: Functions, files, and dependencies for Jonathan Templin's EPSY 905 course

Description

Used for reshaping data more extensively than the reshape, melt, or reshape2 functions available. Can reshape multiple wide-format variables into long format.

Usage

MultiWide2Long(data, idvars, varlist, timevals = 1:length(varlist[[1]]),
  timevar = "time")

Arguments

data	A data frame that is wide format.
idvars	The id variable(s) that identify multiple records from the same unit.
varlist	A list of length equal to the number of variables to be reshaped from wide to long. The names of the elements will make up the names of the new long-format variables. Each element of the list is a character vector that contains the variable names in data that are to be reshaped. All elements must have character vectors of the same length.
timevals	A vector of numbers to use for time. Length must be equal to the size of the elements in varlist. Can be NA for no time.
timevar	A character containing the name of the new time variable. Can be NA for default name or no name if timevar is NA.

Value

A data frome in long format

Examples

summary(Indometh)
wide <- reshape(Indometh, v.names = "conc", idvar = "Subject",
                timevar = "time", direction = "wide")
#add additional column so reshape has same size for two variables
wide$conc.9 = runif(n = 6, min = 0, max = .05)
wide


  long <- MultiWide2Long(data = wide, idvars = "Subject",
                         varlist =
                           list(ConcLE2 =
                                  c("conc.0.25",
                                    "conc.0.5",
                                    "conc.0.75",
                                    "conc.1",
                                    "conc.1.25",
                                    "conc.2"),
                                ConcGT2 =
                                  c("conc.3",
                                    "conc.4",
                                    "conc.5",
                                    "conc.6",
                                    "conc.8",
                                    "conc.9")),
                         timevals = 1:6, timevar = "time")
  long

jonathantemplin/EPSY905R documentation built on May 19, 2019, 4:06 p.m.