Visual Servoing Platform  version 3.0.0
vpGaussRand.cpp
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29  *
30  * Description:
31  * Generation of random number with uniform and normal probability density.
32  *
33  * Authors:
34  * Eric Marchand
35  *
36  *****************************************************************************/
37 
38 #include <math.h>
39 #include <visp3/core/vpGaussRand.h>
40 
48 double
49 vpGaussRand::gaussianDraw()
50 {
51  double v1, v2, rsq;
52  static bool AlreadyDone = false;
53  static double x2;
54 
55  if (AlreadyDone) {
56  AlreadyDone=false;
57  return x2;
58  }
59 
60  else {
61 
62  do {
63  v1=2*draw1()-1;
64  v2=2*draw1()-1;
65  rsq=v1*v1+v2*v2;
66  } while (rsq >= 1);
67 
68  double fac=sqrt(-2*log(rsq)/rsq);
69  x2=v2*fac;
70  AlreadyDone=true;
71  return v1*fac;
72  }
73 }
double draw1()
Definition: vpUniRand.cpp:62