double BCAL_tdiff_res(double geometric_mean, int ilayer) { double &x = geometric_mean; switch(ilayer){ case 1: return 0.181385+(0.243128/(pow(x,0.180288)-1.84364)); break; case 2: return 0.257368+(23.5305/(pow(x,0.957295)-20.7751)); break; case 3: return 100.0; break; case 4: case 5: case 6: case 7: case 8: case 9: case 10: return 100.0; } return 1000.0; }