ProgOne pairings

pairings.R

library(reshape2)

get_pairs <- function(people)
{
	require(reshape2)

	# Create matrix of all possible pairings
	# Only use pairings on diagonal with an offset of half the number of people
	# This ensures that there is equal spacing between each person's turn to present (as def or pros)
	p <- rep(people, 2)
	x <- matrix(0, length(p), length(p))
	rownames(x) <- p
	colnames(x) <- p

	# Get offset coordinates
	n <- round(length(people)/2)+1
	n1 <- n:ncol(x)
	x[cbind(seq(n1), n1)] <- 1

	# Get pairings
	dat <- subset(melt(x), value==1)[1:length(people),1:2]
	names(dat) <- c("defendant", "prosecutor")
	rownames(dat) <- NULL
	return(dat)
}

set.seed(100)
people <- c("gib", "david", "jack", "hannah", "neil", "lavinia", "luisa", "eleanor", "evie")

# Get pairings using get_pairs
# For each round shuffle the order of the people so that the pairings are different
rounds <- 3
l <- list()
for(i in 1:rounds)
{
	l[[i]] <- get_pairs(sample(people))
}
dat <- do.call(rbind, l)
write.csv(dat, file="pairs.csv")