// This function contributed by Andrew W. Steiner <*****@*****.**>
int test_bicubic_nonlinear_nonsq() {
int status;
double xarr[] = {1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0};
double yarr[] = {1.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 16.0};
double zarr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
2, 2, 6, 4, 10, 6, 14, 8, 11, 12,
3, 6, 3, 12, 15, 6, 21, 24, 13, 14,
4, 4, 12, 4, 20, 12, 28, 8, 15, 16,
5, 10, 15, 20, 5, 30, 35, 40, 17, 18,
6, 6, 6, 12, 30, 6, 42, 24, 19, 20,
7, 14, 21, 28, 35, 42, 7, 56, 21, 22,
8, 8, 24, 8, 40, 24, 56, 8, 23, 24};
double xval[] = {1.4, 2.3, 9.7, 3.3, 9.5, 6.6, 5.1};
double yval[] = {1.0, 1.8, 1.9, 2.5, 2.7, 4.1, 3.3};
// results computed using GSL 1D cubic interpolation twice
double zval[]={1.4,2.46782030941187003,10.7717721621846465,
4.80725067958096375,11.6747032398627297,
11.2619968682970111,9.00168877916872567};
size_t xsize = sizeof(xarr) / sizeof(xarr[0]);
size_t ysize = sizeof(yarr) / sizeof(yarr[0]);
size_t test_size = sizeof(xval) / sizeof(xval[0]);
status = test_interp2d(xarr, yarr, zarr, xsize, ysize, xval, yval, zval, NULL, NULL, NULL, NULL, NULL, test_size, interp2d_bicubic);
gsl_test(status, "bicubic interpolation on nonlinear symmetric function");
return status;
}
static int
test_bicubic_nonlinear()
{
int status;
double xarr[] = {1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0};
double yarr[] = {1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0};
/* least common multiple of x and y */
double zarr[] = { 1, 2, 3, 4, 5, 6, 7, 8,
2, 2, 6, 4, 10, 6, 14, 8,
3, 6, 3, 12, 15, 6, 21, 24,
4, 4, 12, 4, 20, 12, 28, 8,
5, 10, 15, 20, 5, 30, 35, 40,
6, 6, 6, 12, 30, 6, 42, 24,
7, 14, 21, 28, 35, 42, 7, 56,
8, 8, 24, 8, 40, 24, 56, 8};
double xval[] = {1.4, 2.3, 4.7, 3.3, 7.5, 6.6, 5.1};
double yval[] = {1.0, 1.8, 1.9, 2.5, 2.7, 4.1, 3.3};
/* results computed using GSL 1D cubic interpolation twice */
double zval[] = { 1.4, 3.11183531264736, 8.27114315792559, 5.03218982537718,
22.13230634702637, 23.63206834997871, 17.28553080971182 };
size_t xsize = sizeof(xarr) / sizeof(xarr[0]);
size_t ysize = sizeof(yarr) / sizeof(yarr[0]);
size_t test_size = sizeof(xval) / sizeof(xval[0]);
status = test_interp2d(xarr, yarr, zarr, xsize, ysize, xval, yval, zval,
NULL, NULL, NULL, NULL, NULL, test_size,
gsl_interp2d_bicubic);
gsl_test(status, "bicubic interpolation on nonlinear symmetric function");
return status;
}
/*
* Tests bilinear interpolation with an asymmetric function, f(x,y)!=f(y,x),
* and off-diagonal interpolation points (x,y) where x and y may or may not
* be equal.
*/
static int
test_bilinear_asymmetric_z()
{
int status;
double xarr[] = {0.0, 1.0, 2.0, 3.0};
double yarr[] = {0.0, 1.0, 2.0, 3.0};
double zarr[] = {1.0, 1.1, 1.2, 1.4,
1.3, 1.4, 1.5, 1.7,
1.5, 1.6, 1.7, 1.9,
1.6, 1.9, 2.2, 2.3};
double xval[] = { 0.0, 0.5, 1.0, 1.5, 2.5, 3.0,
1.3954, 1.6476, 0.824957,
2.41108, 2.98619, 1.36485 };
double yval[] = {0.0, 0.5, 1.0, 1.5, 2.5, 3.0,
0.265371, 2.13849, 1.62114,
1.22198, 0.724681, 0.0596087 };
/* results computed using Mathematica 9.0.1.0 */
double zval[] = {1.0, 1.2, 1.4, 1.55, 2.025, 2.3,
1.2191513, 1.7242442248, 1.5067237,
1.626612, 1.6146423, 1.15436761};
size_t xsize = sizeof(xarr) / sizeof(xarr[0]);
size_t ysize = sizeof(yarr) / sizeof(yarr[0]);
size_t test_size = sizeof(xval) / sizeof(xval[0]);
status = test_interp2d(xarr, yarr, zarr, xsize, ysize, xval, yval, zval,
NULL, NULL, NULL, NULL, NULL, test_size,
gsl_interp2d_bilinear);
gsl_test(status, "bilinear interpolation with asymmetric z values");
return status;
}
void test_bicubic() {
int status;
double xarr[] = {0.0, 1.0, 2.0, 3.0};
double yarr[] = {0.0, 1.0, 2.0, 3.0};
double zarr[] = {1.0, 1.1, 1.2, 1.3,
1.1, 1.2, 1.3, 1.4,
1.2, 1.3, 1.4, 1.5,
1.3, 1.4, 1.5, 1.6};
double xval[] = {1.0, 1.5, 2.0};
double yval[] = {1.0, 1.5, 2.0};
double zval[] = {1.2, 1.3, 1.4};
size_t xsize = sizeof(xarr) / sizeof(xarr[0]);
size_t ysize = sizeof(yarr) / sizeof(yarr[0]);
size_t test_size = sizeof(xval) / sizeof(xval[0]);
status = test_interp2d(xarr, yarr, zarr, xsize, ysize, xval, yval, zval, NULL, NULL, NULL, NULL, NULL, test_size, interp2d_bicubic);
gsl_test(status, "bicubic interpolation on linear function");
}
/**
* Tests bilinear interpolation using a symmetric function, f(x,y)==f(y,x),
* and diagonal interpolation points (x,y) where x==y. If these tests don't pass,
* something is seriously broken.
*/
int test_bilinear_symmetric() {
int status;
double xarr[] = {0.0, 1.0, 2.0, 3.0};
double yarr[] = {0.0, 1.0, 2.0, 3.0};
double zarr[] = {1.0, 1.1, 1.2, 1.3,
1.1, 1.2, 1.3, 1.4,
1.2, 1.3, 1.4, 1.5,
1.3, 1.4, 1.5, 1.6};
double xval[] = {0.0, 0.5, 1.0, 1.5, 2.5, 3.0};
double yval[] = {0.0, 0.5, 1.0, 1.5, 2.5, 3.0};
double zval[] = {1.0, 1.1, 1.2, 1.3, 1.5, 1.6};
size_t xsize = sizeof(xarr) / sizeof(xarr[0]);
size_t ysize = sizeof(yarr) / sizeof(yarr[0]);
size_t test_size = sizeof(xval) / sizeof(xval[0]);
status = test_interp2d(xarr, yarr, zarr, xsize, ysize, xval, yval, zval, NULL, NULL, NULL, NULL, NULL, test_size, interp2d_bilinear);
gsl_test(status, "bilinear interpolation with symmetric values");
return status;
}
