PLOT 2D graph and matrices

I'm trying to solve this 2D problem in matlab,

for a given matrices (2*2 dimension for example) using the following notations :

A frequency-domain representation of the matrix K

sigma=the maximum singular value of matrix K;

the fist axis is p and the secon axis is s where 1<p<4 and 1<s<4 and

K=[p-1 -2; -3 s-4]

how to ( compute and plot ) the surf that represnt each pair (p,s) the ( sigma=the maximum singular value of matrix K) like this graph ( note that this graph is for a nother example ),

it's mean: the first axis: p, the second axis: s, and the third axis: we have the maximum singular value of matrix K

Answer 1

[SALAH ALRABEEI]

You need to define several values of p and s, then find the svds of K for each value of k p and s; See thebexample below

 p=1.1:0.1:3.9;
s=p
for i =1:length(p)
for j =1: length(s)
pi = p(i); sj = s(j);
K=[pi-1 -2; -3 sj-4];
M(i,j) = svds(K,1);
end
end
surf(p,s,M)

[Lewis Fer]

thank you so much SALAH!! this is the result I I forgot to use svds command.