matlab中输出中间值的命令是什么啊？

想要那个值你就用disp()去显示

function rk(A,x,h,y0)
i=1;
y(i,:)=y0;
m=length(A);
b=x(length(x));
while x(i)<b
     a=[x(i),y(i,:)];
    for l=1:m
         k1(l)=eval(A{l},a);
    end
     a=[x(i)+h/2,y(i,:)+h/2*k1];
    for l=1:l
         k2(l)=eval(A{l},a);
    end
     a=[x(i)+h/2,y(i,:)+h/2*k2];
    for l=1:m
         k3(l)=eval(A{l},a);
    end
     a=[x(i)+h,y(i,:)+h*k3];
    for l=1:m
         k4(l)=eval(A{l},a);
    end
     y(i+1,:)=y(i,:)+h/6*(k1+2*k2+2*k3+k4);
     i=i+1;
end
y,k1,k2,k3,k4

我想把中间过程的k1,k2,k3,k4和yi值都显示出来，结果不行如下：
y1='-10*a(2)-9*a(3)+8';
y2='-9*a(2)-8*a(3)+7';
A=[{y1},{y2}];
rk(A,0:0.05:1,0.05,ones(1,2))

y =

    1.0000    1.0000
    0.6417    0.6716
    0.4972    0.5345
    0.4403    0.4758
    0.4193    0.4491
    0.4129    0.4356
    0.4126    0.4275
    0.4148    0.4216
    0.4181    0.4166
    0.4217    0.4120
    0.4255    0.4075
    0.4294    0.4030
    0.4334    0.3986
    0.4373    0.3941
    0.4413    0.3897
    0.4453    0.3852
    0.4493    0.3807
    0.4533    0.3762
    0.4574    0.3717
    0.4614    0.3672
    0.4655    0.3627


k1 =

    0.0809   -0.0904


k2 =

    0.0811   -0.0906


k3 =

    0.0811   -0.0906


k4 =

    0.0812   -0.0907

请大侠指教，谢谢