Source code in the icon programming language

link numbers     # for a/g/h means

procedure main()
every put(x := [], 1 to 10)
writes("x := [ "); every writes(!x," "); write("]")

write("Arithmetic mean:", a := amean!x)
write("Geometric mean:",g := gmean!x)
write("Harmonic mean:", h := hmean!x)
write(" a >= g >= h is ", if a >= g >= h then "true" else "false")
end


procedure amean(L[])		#: arithmetic mean
   local m
   if *L = 0 then fail
   m := 0.0
   every m +:= !L
   return m / *L
end

procedure gmean(L[])		#: geometric mean
   local m
   if *L = 0 then fail
   m := 1.0
   every m *:= !L
   m := abs(m)
   if m > 0.0 then
      return exp (log(m) / *L)
   else
      fail
end
   
procedure hmean(L[])		#: harmonic mean
   local m, r
   if *L = 0 then fail
   m := 0.0
   every r := !L do {
      if r = 0.0 then fail
      else m +:= 1.0 / r
      }
   return *L / m
end