Please How I can use meshgrid with x and y are the elements of the matrix A and plot a figure like in the picture

x = linspace(0,3);
y = linspace(-2*pi,2*pi);
[X,Y] = meshgrid(x,y);
A=[x,2;0,y];
Z = exp(det(A)) + cos(Y);
contourf(X,Y,Z)

Answer 1

[Walter Roberson]

This does not look like a contour plot at first, but notice the upper right corner.

syms P Q
D = det([P, 2; 0, Q]);
x = linspace(0,3);
y = linspace(-2*pi,2*pi);
[X,Y] = meshgrid(x,y);
A = double(subs(D, {P,Q}, {X, Y}));
Z = exp(A) + cos(Y);
contourf(X, Y, Z)

[Abdelkader Hd]

@Walter Roberson Thank you br.