double fU(double q){
return ( pow(q,2.0) / 4.0 );
}
double fZ(double q){
return ( 1.0 + pow(q,2.0) / 4.0 );
}
double fP(double q, double p){
return ( 1.0 - fU(q) / pow(fZ(q),2.0) * log (1.0/p) ) * pow ( p, 1.0/fZ(p) );
}
void main(void)
{
double r1 = fP(5.0, pow(10.0,-6.0));
double r2 = fP(10.0, pow(10.0,-4.0));
double r3 = fP(15.0, pow(10.0,-2.0));
}