R/voltriangle.R

In denpro: Visualization of Multivariate Functions, Sets, and Data

voltriangle<-function(simp)
{
# simp is (d+1)*d matrix  / 3*2 matrix
# Heron's formula

v1<-simp[1,]
v2<-simp[2,]
v3<-simp[3,]

a<-sqrt( sum((v1-v2)^2) )
b<-sqrt( sum((v1-v3)^2) )
c<-sqrt( sum((v2-v3)^2) )

s<-(a+b+c)/2
vol<-sqrt( s*(s-a)*(s-b)*(s-c) )

return(vol)
}