How to deal with floating point errors in R

Question

Consider the following R function

is.sqrt <- function(x, y){
  if(x^2 == y) TRUE
  else FALSE
}

which answers whether x is the square ro

Answer 1

You can use the near function from dplyr, it has a built-in tolerance.

is.sqrt <- function(x, y) {
  near(x^2, y)
}

is.sqrt(sqrt(2), 2)

> TRUE