1 #include <extUtil.h>
2 
3 /* angle between two vectors in rad */
v_angle(double * v0,double * v1)4 double v_angle( double *v0, double *v1 )
5 {
6   double vn0[3], vn1[3];
7   double fi;
8 
9     v_norm(  v0, vn0 );
10     v_norm(  v1, vn1 );
11     /* winkel zwischen den Vektoren */
12     fi=v_sprod( vn0, vn1 );
13     return(acos(fi));
14 }
15