[R] Testing if all elements are equal in a vector/matrix

Vincent Goulet
Mon, 29 Aug 2005 19:35:21 -0000

Is there a canonical way to check if all elements of a vector or matrix are
the same? Solutions below work, but look hackish to me.

> x <- rep(1, 10)
> all(x == x[1])  # == operator does not provide for small differences
[1] TRUE
> isTRUE(all.equal(x, rep(x[1], length(x)))) # ugly
[1] TRUE

Best,

Vincent
--
  Vincent Goulet, Associate Professor
  ??cole d'actuariat
  Universit?? Laval, Qu??bec
  Vincent.Goulet at act.ulaval.ca   http://vgoulet.act.ulaval.ca