Set vector coefficients a box at a time.
Set vector coefficients a box at a time. The data in values is ordered
as follows:
m = 0;
for (k = ilower[2]; k <= iupper[2]; k++)
for (j = ilower[1]; j <= iupper[1]; j++)
for (i = ilower[0]; i <= iupper[0]; i++)
{
values[m] = ...;
m++;
}