R/calcEhiergaus.R

In glotaran/TIMP: Fitting Separable Nonlinear Models in Spectroscopy and Microscopy

"calcEhiergaus" <-
  function(theta, lambda, nupower) {
    spec <- matrix(data = 0, ncol = length(theta), nrow = length(lambda))
    for (i in 1:length(theta)) {
      npare <- ifelse(length(theta[[i]]) == 3, 3, 4)
      for (j in 1:(length(theta[[i]]) / npare)) {
        joff <- (j - 1) * npare
        a <- ifelse(npare == 3, 1, theta[[i]][joff + 4])
        if (theta[[i]][joff + 3] != 0) {
          spec[, i] <- spec[, i] +
            a * skew(
              theta[[i]][joff + 1],
              theta[[i]][joff + 2],
              theta[[i]][joff + 3], l2nu(lambda),
              nupower
            )
        } else {
          spec[, i] <- spec[, i] + a * gaus(
            theta[[i]][joff + 1],
            theta[[i]][joff + 2],
            l2nu(lambda), nupower
          )
        }
      }
    }
    spec
  }