R/squeezing.R

In dylandaniels/ars:

# Computes the squeezing function.
# Import h(x), abscissae, and x value
# Returns l(x)
squeezing <- function(hx,abscissae,x){
  k <- length(abscissae)
  if (x < abscissae[1] || x > abscissae[k]) {
    return (-Inf)
  }
  for(i in 1:(k-1)) {
    if(x >= abscissae[i] && x <= abscissae[i+1]) {
      return (((abscissae[i+1]-x)*hx[i]+(x-abscissae[i])*hx[i+1])/(abscissae[i+1]-abscissae[i]))
    }
  }
}