compound_interest.R

compound.R

# How much interest etc. would you pay for a mortgage?

compound <- function(rate, money, n) {
  prin <- money * (1+rate/100)^(0:(n-1))
  int  <- prin * (rate/100)
  totalInt <- sum(int)
  totalMoney <- money + totalInt
  rentpermonth <- totalMoney / (n * 12)
  textTable <- c(
                 cat(rep("=", 30), "\n ", sep=""),
                 "Rate: %g \n",
                 "Money: %g \n",
                 "Year: %g \n",
                 "Total Interest: %g \n",
                 "Total Money: %g \n",
                 "Rent Per Month: %g \n"
                )
  cat(
    sprintf(paste(textTable, collapse = " "), 
            rate, money, n, totalInt, totalMoney, rentpermonth)
  )
}

# Run an example:
compound(rate = 0.99, money = 350000, n = 30)
compound(rate = 0.21, money = 250000, n = 30)