| dfOrder {psych} | R Documentation |
Although order will order a vector, and it is possible to order several columns of a data.frame by specifying each column individually in the call to order, dfOrder will order a dataframe by as many columns as desired.
dfOrder(object, columns)
object |
The data.frame to be sorted |
columns |
Column numbers to use for sorting. If positive, then they will be sorted in increasing order. If negative, then in decreasing order |
This is just a simple helper function to reorder data.frames. Originally developed to organize IRT output from the ltm package. It is a basic add on to the order function.
The original data frame is now in sorted order.
William Revelle
This code is used in the test.irt function to combine ltm and sim.irt output.
x <- data.frame(matrix(sample(1:4,64,replace=TRUE),ncol=4)) dfOrder(x) # sort by all columns dfOrder(x,c(1,4)) #sort by the first and 4th column dfOrder(x,c(1,-2)) #sort by the first in increaseing order, #the second in decreasing order