asymLD (version 0.1)

lsort: Sort a data.frame.

Description

A function to sort a data.frame on specific columns.

Usage

lsort(dat, by = 1:dim(dat)[2], asc = rep(TRUE, length(by)), na.last = TRUE)

Arguments

dat

a dataframe or a matrix ("dimnames" are used as the variable names for a matrix)

by

a vector or a list of variable names or column indices specifying the "sort by" variables, the default is to sort by all variables in the order they appear in the data set.

asc

a vector with the same length as "by" indicating whether the sorting of each "by" variable is in ascending order, the default order is ascending.

na.last

a flag indicating whether missing values are placed as the last elements in the data set, the default is TRUE

Value

The return value is a sorted dataframe.

Details

The input dataframe is not modified. The code is adapted from code posted to an old s-news listserve.

Examples

## Not run: 
# library(asymLD)
# data(snp.freqs)
# 
# # sort snp.freqs by "locus1" (ascending) and "allele1" (descending)
# newdata <- lsort(snp.freqs, by=c("locus1","allele1"), asc=c(T,F))
# head(newdata)
# # sort snp.freqs by the fourth and the second variable (ascending)
# newdata <- lsort(snp.freqs, by=c(4,2))
# # sort "snp.freqs" by "locus1" and the 5th variable (ascending)
# newdata <- lsort(snp.freqs, by=list("locus1",5))
# 
# ## End(Not run)