Random DD stuff

DDCalc.R

## Define function that will convert temperatures to Celcius and divide by 8 [same as * 1/8] (as each measurement represents 1/8 of a day)
#Note: need to add a part here where any value <0 = 0 and not a negative, as heating DD's are calculated only using the 'above the threshold'
extractDD=function(path) {
  vals=(values(raster(path,varname="TMP"))-273.15)/8
  if(vals < 0) {
    vals = 0
  }
  if (sum(is.na(vals))>0)
    stop(paste0("this raster has na values: ", path))
  return(vals)
}