diff --git a/src/experimental/_impl/_pnoise1.scad b/src/experimental/_impl/_pnoise1.scad
index 2d0cbc26..c58dc56a 100644
--- a/src/experimental/_impl/_pnoise1.scad
+++ b/src/experimental/_impl/_pnoise1.scad
@@ -3,7 +3,7 @@ use <experimental/_impl/_pnoise_comm.scad>;
 function _pnoise1(x, seed) =
     let(
         xi = floor(x),
-        xf = x - floor(x),
+        xf = x - xi,
         u = _pnoise_fade(xf),
         a = _pnoise_lookup_poise_table(seed + xi),
         b = _pnoise_lookup_poise_table(seed + xi + 1)