R/reduce-fraction.R

In pmcharrison/incon: Computational Models of Simultaneous Consonance

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# Copyright (c) 2022 Santiago Barreda
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reduce_fraction <- function(ratio) {
  if (length(ratio) != 2)
    stop("Ratio must contain two numbers.")
  if (ratio[1] %% 1 > 0 | ratio[2] %% 1 > 0)
    stop("Elements of ratio must be whole numbers.")
  numerator = ratio[1]
  denominator = ratio[2]
  remainder = -1
  while (remainder != 0) {
    remainder = numerator %% denominator
    numerator = denominator
    if (remainder != 0)
      denominator = remainder
  }
  ratio = ratio / denominator
  return(ratio)
}