funfun(data, expr='log(x1/x2)*10^2')

Apply a custom arithmetic expression to columns of a data frame using column aliases x1, x2…

utility

Args:data — data frameexpr — R expression string with x1/x2/… as column placeholders

funfun <- function(data, expr = "log(x1 / x2) * 10^2") {
  expr <- parse(text = expr)
  data %>% mutate(x3 = eval(expr))
}