R/index.internal.var.R

In SantanderMetGroup/R_VALUE: Climate data validation in the framework of the COST action VALUE

index.internal.var <- function(ts, dates, type = c("monthly","interannual")) {
  type <- match.arg(type, choices = c("monthly", "interannual"))
  if (type=="monthly"){
    mon <- substr(dates, 1,7)
    ref <- var(tapply(ts, INDEX = mon, FUN = mean, na.rm = TRUE))
  }
  if (type=="interannual"){
    yea <- substr(dates, 1,4)
    ref <- var(tapply(ts, INDEX = yea, FUN = mean, na.rm = TRUE))  
  }
  return(ref)  
}