regression/nextAfter.sml

   1 functor Test (R: REAL) =
   2 struct
   3
   4 open R
   5
   6 val posZero = minPos - minPos
   7 val negZero = ~posZero
   8
   9 val rs =
  10    [(negZero, negZero, negZero),
  11     (negZero, posZero, posZero),
  12     (posZero, negZero, negZero),
  13     (posZero, posZero, posZero),
  14     (negZero, posInf, minPos),
  15     (negZero, negInf, ~minPos),
  16     (posZero, posInf, minPos),
  17     (posZero, negInf, ~minPos),
  18     (minPos, posZero, posZero),
  19     (minPos, negZero, posZero),
  20     (minPos, negInf, posZero),
  21     (~minPos, posZero, negZero),
  22     (~minPos, negZero, negZero),
  23     (~minPos, posInf, negZero),
  24     (minPos, minPos, minPos),
  25     (~minPos, ~minPos, ~minPos),
  26     (minPos, posInf, fromInt 2 * minPos),
  27     (~minPos, negInf, ~(fromInt 2 * minPos)),
  28     (maxFinite, posInf, posInf),
  29     (~maxFinite, negInf, negInf),
  30     (nextAfter (minNormalPos, negInf), posInf, minNormalPos)]
  31
  32 val () =
  33    List.app
  34    (fn (x, y, z) =>
  35     let
  36        val r2s = fmt StringCvt.EXACT
  37        val z' = nextAfter (x, y)
  38     in
  39        print (concat ["nextAfter (", r2s x, ", ", r2s y, ") = ", r2s z', " ",
  40                       if == (z, z') then "OK" else concat ["<> ", r2s z],
  41                       "\n"])
  42     end)
  43    rs
  44
  45 end
  46
  47 structure Z = Test (Real32)
  48 structure Z = Test (Real64)
  49