bool compare_ensembles( swarm::ensemble& e1, swarm::ensemble &e2 , double & pos_diff, double & vel_diff, double & time_diff ) {
if (e1.nsys() != e2.nsys() || e1.nbod() != e2.nbod() ) return false;
pos_diff = vel_diff = time_diff = 0;
for(int i = 0; i < e1.nsys(); i++) {
for(int j = 0; j < e1.nbod() ; j++){
// Distance between body position in ensemble e1 and e2
double dp = sqrt(
square ( e1[i][j][0].pos() - e2[i][j][0].pos() )
+ square ( e1[i][j][1].pos() - e2[i][j][1].pos() )
+ square ( e1[i][j][2].pos() - e2[i][j][2].pos() ) ) ;
// Average magnitude of the position in e1 and e2
double ap = sqrt(
square ( e1[i][j][0].pos() + e2[i][j][0].pos() )
+ square ( e1[i][j][1].pos() + e2[i][j][1].pos() )
+ square ( e1[i][j][2].pos() + e2[i][j][2].pos() ) ) / 2.0 ;
// Difference between body velocities in ensemble e1 and e2
double dv = sqrt(
square ( e1[i][j][0].vel() - e2[i][j][0].vel() )
+ square ( e1[i][j][1].vel() - e2[i][j][1].vel() )
+ square ( e1[i][j][2].vel() - e2[i][j][2].vel() ) ) ;
// Average magnitude of the velocity in e1 and e2
double av = sqrt(
square ( e1[i][j][0].vel() + e2[i][j][0].vel() )
+ square ( e1[i][j][1].vel() + e2[i][j][1].vel() )
+ square ( e1[i][j][2].vel() + e2[i][j][2].vel() ) ) / 2.0 ;
if ( dp > pos_diff ) pos_diff = dp;
if ( dv > vel_diff ) vel_diff = dv;
}
// Difference between time divided by average of the two
double dt = fabs(e1[i].time() - e2[i].time())
/(e1[i].time() + e2[i].time())*2;
if ( dt > time_diff ) time_diff = dt;
}
return true;
}
void print_selected_systems_for_demo(swarm::ensemble& ens, unsigned int nprint, std::ostream &os = std::cout)
{
if(nprint>ens.nsys()) nprint = ens.nsys();
for(unsigned int systemid = 0; systemid< nprint; ++systemid)
print_system(ens,systemid,os);
}