if(hu>=0.81*hz*pow((hz/gg),0.72)) cd=0.611*pow((hu-gg)/(hu+15*gg),0.072);
else cd=0.611*pow((hu-gg)/(hu+15*gg),0.072)*pow((hu-hz),0.7)*pow((0.32*pow((0.81*hz*pow((hz/gg),0.72)-hu),0.7)+pow((hu-hz),0.7)),-1);

可以啊，可以理解成几次根号下。。。