Add hollow cone vector generation example.

* examples/generate-hollow-cone-vector.c: New file.

1 files changed, 32 insertions, 0 deletions

diff --git a/examples/generate-hollow-cone-vector.c b/examples/generate-hollow-cone-vector.c
new file mode 100644
index 0000000..52cdc2d
--- /dev/null
+++ b/examples/generate-hollow-cone-vector.c
@@ -0,0 +1,32 @@
+#include <nd-random.h>
+
+// Dimension of the vector to generate
+#define DIMENSION 10
+// Minimum angle from the axis of the cone
+#define THETA_MIN M_PI/4
+// Maximum angle from the axis of the cone
+#define THETA_MAX M_PI/3
+
+int main ()
+{
+  // Initialize random number generator.
+  gsl_rng_env_setup();
+  gsl_rng* r = gsl_rng_alloc(gsl_rng_default);
+  // Allocate vector to be generated.
+  gsl_vector *x = gsl_vector_alloc(DIMENSION);
+  // Allocate and initialize central axis of cone.
+  gsl_vector *axis = gsl_vector_alloc(DIMENSION);
+  gsl_vector_set_all(axis, 1/sqrt(DIMENSION));
+
+  // Generate random vector on spherical cap of hollow cone.
+  hollow_cone_random_vector(r, axis, THETA_MIN, THETA_MAX, x);
+
+  // Print out generated vector.
+  gsl_vector_fprintf(stdout, x, "%g");
+
+  // Free allocated memory.
+  gsl_vector_free(axis);
+  gsl_vector_free(x);
+  gsl_rng_free(r);
+  return 0;
+}