R/roots.R

In SchroederFabian/CVOC: Classification under varying operating conditions

roots <- function(mu0, mu1, sigma0, sigma1, c0, c1, pi0) {
  
  a <- 1/(2*sigma0^2) - 1/(2*sigma1^2)
  b <- mu1/sigma1^2 - mu0/sigma0^2
  c <- mu0^2/(2*sigma0^2) - mu1^2/(2*sigma1^2) + log(sigma0/sigma1) - log(pi0/(1-pi0)*c0/c1)
  
  if (b^2 - 4*a*c >= 0) { return(c((-b - sqrt(b^2 - 4*a*c)) / (2*a), (-b + sqrt(b^2 - 4*a*c)) / (2*a)))										
  } else {return(c(NA, NA))}
}