mtt: /home/laradmin/lar/perception/planarobstacles/mtt/src/metrics.cpp Source File

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00032 #include <mtt/metrics.h>
00033 
00034 double mahalanobis(Vector2d&y,Vector2d&mean,Matrix2d& cov)
00035 {       
00036         VectorXd a=y-mean;
00037         MatrixXd i= cov.inverse();
00038         double squared=a.transpose()*i*a;
00039         return sqrt(squared);
00040 }
00041 
00042 double biVariatePDF(Vector2d& x,Vector2d& m,Matrix2d& cov)
00043 {
00044         double a,b,c,d,e;
00045         double s1,s2,rho;
00046         
00047         s1=sqrt(cov(0,0));
00048         s2=sqrt(cov(1,1));
00049         rho=cov(0,1)/(s1*s2);
00050         
00051         a=1./(2*M_PI*s1*s2*sqrt(1-rho*rho));
00052         b=1./(2*(1-rho*rho));
00053         c=pow(x(0)-m(0),2)/(s1*s1);
00054         d=pow(x(1)-m(1),2)/(s2*s2);
00055         e=(2*rho*(x(0)-m(0))*(x(1)-m(1)))/(s1*s2);
00056         
00057         double f = a*exp(-b*(c+d-e));
00058 
00059         if(f<1e-12)
00060                 f=0;
00061         
00062         return f;
00063 }