// const REAL quot = std::tan(phiN)*(std::cos(thetaN)*std::cos(thetaT) + std::sin(thetaN)*std::sin(thetaT)) ; // Based on orthogonality
// REAL phiT = -std::atan(1/quot) ; // if quot==0, atan returns Pi/2
REALphiT=-std::atan((std::cos(thetaN)*std::cos(thetaT)+std::sin(thetaN)*std::sin(thetaT))*std::cos(phiN)/std::sin(phiN));// if quot==0, atan returns Pi/2
REALphiT=0.0;
if(std::fabs(phiN)<M_PI/2.0-1e-3)
phiT=-std::atan((std::cos(thetaN)*std::cos(thetaT)+std::sin(thetaN)*std::sin(thetaT))*std::cos(phiN)/std::sin(phiN));// if quot==0, atan returns Pi/2
// if (phiT < 0.0) {
std::cout<<" ; New set = "<<compressedFrame<<phiT<<std::endl;