circumcircles.r

library(tripack)
library(viridis)
library(grDevices)

n <- 40

x <- runif(n)
y <- runif(n)

gr <- expand.grid(c(1:n), c(1:n), c(1:n))
gr <- unique(t(apply(gr, 1, sort)))
alldif <- apply(gr, 1, function(x) length(unique(x)) == length(x))
gr <- gr[alldif,]

pal <- adjustcolor(inferno(1000), alpha=0.4)

plot(x=x, y=y, asp=1, pch=NA)
for(i in c(1:nrow(gr))){
    c = circumcircle(x[gr[i,]], y[gr[i,]], num.touch=3)
    circles(x=c$x, y=c$y, r=c$radius, col=pal[round(c$radius*1000,0)], lwd=2)
}
points(x=x, y=y, pch=21, bg='darkgrey', lwd=9+rnorm(n, mean=0), cex=3+rnorm(n, mean=0), col="lightgrey")