diff --git a/csa/geometry.py b/csa/geometry.py
index c83e470..da9edca 100644
--- a/csa/geometry.py
+++ b/csa/geometry.py
@@ -105,7 +105,9 @@ def grid3d(width, xScale = 1.0, yScale = 1.0, zScale = 1.0, x0 = 0.0, y0 = 0.0,
     yScale /= width
     zScale /= width
     g = lambda i: \
-        (x0 + xScale * (i % width), y0 + yScale * ((i % (width*width)) / width), z0 + zScale * (i / (width*width)))
+        (x0 + xScale * (i % width), 
+         y0 + yScale * ((i % (width*width)) // width), 
+         z0 + zScale * (i // (width*width)))
     g.type = 'grid3d'
     g.width = width
     g.xScale = xScale
@@ -168,4 +170,4 @@ def euclidMetric3d (g1, g2 = None):
     :rtype: function
     """
     g2 = g1 if g2 == None else g2
-    return lambda i, j: euclidDistance3d (g1 (i), g2 (j))
+    return lambda i, j: euclidDistance3d (g1 (i), g2 (j))
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