x=(0:0.1:2);y1=(1/sqrt(2*pi))*(exp^(-(x^2)/2));h1=subplot(2,2,1);plot(x,y1)title('标准正态分布的概率密度曲线') 运行说是??? Error using ==> expNot enough input arguments.Error in ==> Untitled3 at 2y1=(1/sqrt(2*pi))*(exp^(-(x^2)/2));大虾们说下啊