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-rw-r--r--src/gaussian-nd-random.c51
1 files changed, 0 insertions, 51 deletions
diff --git a/src/gaussian-nd-random.c b/src/gaussian-nd-random.c
deleted file mode 100644
index 16abc94..0000000
--- a/src/gaussian-nd-random.c
+++ /dev/null
@@ -1,51 +0,0 @@
-#include <gsl/gsl_blas.h>
-#include <gsl/gsl_randist.h>
-#include <gsl/gsl_sf_gamma.h>
-#include "nd-random.h"
-#include "utils.h"
-
-#define INTEGRATION_EPSABS 1e-3
-#define INTEGRATION_EPSREL 1e-3
-
-unsigned int shifted_gaussian_random_vector
-(const gsl_rng* r, const gsl_vector* mean, double theta_max, double standard_deviation, gsl_vector* x)
-{
-  for (int i=0; i<x->size; i++)
-    gsl_vector_set(x, i, gsl_ran_gaussian(r, standard_deviation));
-  gsl_vector_add(x, mean);
-  gsl_blas_dscal(1/gsl_blas_dnrm2(x), x);
-  if (angle_between_vectors(x, mean) > theta_max)
-    return 1 + shifted_gaussian_random_vector(r, mean, theta_max, standard_deviation, x);
-  else return 1;
-}
-
-double shifted_gaussian_pdf (double theta, double mean, double theta_max,
-                             double standard_deviation, unsigned int dimension, gsl_integration_workspace* w)
-{
-  // NOTE: Due to the rejection sampling, the returned result is only
-  // proportional to the actual PDF.
-  if (theta > theta_max) return 0;
-  
-  double projection = mean*cos(theta);
-  double integrand (double r, void* params)
-  {
-    return gsl_pow_uint(r, dimension - 1)
-      * gaussian_pdf((r - projection) / standard_deviation);
-  }
-  
-  gsl_function gsl_integrand = {&integrand};
-  double result, error;
-  /* gsl_integration_qagiu(&gsl_integrand, 0, INTEGRATION_EPSABS, INTEGRATION_EPSREL, */
-  /*                       w->limit, w, &result, &error); */
-  double rmax = 0.5 * (projection + sqrt(gsl_pow_2(projection) + 4*(dimension-1)*gsl_pow_2(standard_deviation)));
-  double halfwidth = 3 * standard_deviation;
-  gsl_integration_qag(&gsl_integrand,
-                      rmax - halfwidth < 0 ? 0 : rmax - halfwidth,
-                      rmax + halfwidth,
-                      INTEGRATION_EPSABS, INTEGRATION_EPSREL,
-                      w->limit, GSL_INTEG_GAUSS41, w, &result, &error);
-  return result
-    * gaussian_pdf(sqrt(gsl_pow_2(mean) - gsl_pow_2(projection)) / standard_deviation)
-    / gsl_pow_uint(M_SQRT2*sqrt(M_PI), dimension - 2)
-    / gsl_pow_uint(standard_deviation, dimension);
-}