Match does not work

match, r

Solution

The right way to deal with floating point errors is to use `all.equal`. Here is a custom function for applying `match` to numerics and accounting for the possibility of floating point errors:

match.numeric <- function(x, table) {
   are.equal <- function(x, y) isTRUE(all.equal(x, y))
   match.one <- function(x, table)
      match(TRUE, vapply(table, are.equal, logical(1L), x = x))
   vapply(x, match.one, integer(1L), table)
}

match.numeric(c(tifl.e, tifc.e, tifr.e), t)
# [1] 26 36 46
match.numeric(c(tifl.m, tifc.m, tifr.m), t)
# [1] 25 37 49

Problem

I was trying to match a numeric to a vector, as following: ``` t <- seq(-4,4,length=81) tifl.e <--1.5 tifc.e <--0.5 tifr.e <-0.5 tifl.m <--1.6 tifc.m <--0.4 tifr.m <-0.8 match( c(tifl.e, tifc.e, tifr.e), t) [1] 26 36 46 match( c(tifl.m, tifc.m, tifr.m), t) [1] NA NA NA ``` I also tried the code, but it gave the same results. ``` tifl.cut <-c(-1.5,-1.6) tifc.cut <-c(-0.5,-0.4) tifr.cut <-c(0.5,0.8) match( c(tifl.cut[1], tifc.cut[1], tifr.cut[1]), t) [1] 26 36 46 match( c(tifl.cut[2], tifc.cut[2], tifr.cut[2]), t) [1] NA NA NA ``` Meanwhile, I tried similar syntax by using %in%, which produced the exact same results. So what is the problem in the syntax? How should I fix it? Thanks for your inputs.

Original source