How to use the result of my matrix calculation to create 2D plot

I tried to plot my the result of my matrix calculation. However, my matlab said that my calculation result lambda1 or Z is not a matrix so I cannot plot without using the command plot3. But I have to plot the 2D figure with different colors represent different result of lambda1. And the commands like pcolor and color require my results to be matrix. What should I do?

n1 = 1.5;

n2 = 3.0;

b1 = 8*10.^(-18);

c1 = pi*10.^(-13);

k1 = (2*pi)*n1;

k2 = (2*pi)*n2;

d1 = [1 1; k1 -k1];

d2 = [1 1; k2 -k2];

t1 = inv(d1);

t2 = inv(d2);

for l1= 1:0.1:10

for l2= 1:0.1:10

p2= [exp(i*k2*l2) 0; 0 exp(-i*k2*l2)];

p1= [exp(i*k1*l1) 0; 0 exp(-i*k1*l1)];

M = t1*d2*p2*t2*d1*p1;

M1= real(M);

[X,Y]= eig(M1);

lambda1 = [0 1]*Y*[0;1];

lambda2 = real([1 0]*Y*[1;0]);

Z = lambda1;

hold on

end

end

pcolor(l1,l2,Z)

[KALYAN ACHARJYA]

Formulate the question in an easy way so that it can be understood easily.

Answer 1

[Daniel M]

l1,l2, and Z are all a single value. You need to understand how to store values in a for loop:

https://www.mathworks.com/help/matlab/ref/for.html

[Jun Xiao]

Thank you for the instruction. I know how to store value Z in a for loop now. But, I still don't know why my variants l1 and l2 cannot be stored as common for loop always did. Can you point it for me?

[Daniel M]

Those variables don't really exist outside of the for loop. They look like vectors, but they're not. Their value is only the value of that iteration, and therefore outside of the loop they only keep the value of the last iteration. Just recreate them after the loop.