P0=0.3; P1=0.7;最佳门限lamda0=0.429时 P0=0.5; P1=0.5;最佳门限lamda0=1时(P0=0.3; P1=0.7; optimal threshold lamda0=0.429 P0=0.5; P1=0.5; optimal threshold lamda0=1)