// EXAMPLE chebyVol surface
   
   function chebychev(x) {
     xx := x * x;
     xx * xx - 2 * xx + 1;
   }
   
   n := 20;
   
// Allocate vol to be a cube, then fill with 0..n-1 uniform coordinate
// indices in 3D.

   vol := (short)index_fill([n, n, n, 3]);
   float res[n, n, n] = 0;
   
// Scale vol to lie in the range -2..2 and apply the chebychev() function
// pointwise throughout vol. Perform a sum-reduction over the XYZ vector
// to compute the result, which is returned as a scalar lattice.

   res += chebychev(vol * (4.0/n) - 2);
   First_Out := scalar_lattice_out(res);