MATLAB: Problem in Eigen values plot

eigenvalues

I would like to plot the First five minimum eigenvalues in assending order w.r.t. ''g '' of the following Matrix using for loop. But am really confuse to sort the minimum eigevlaues. Can anybody help me to solve that?
clc;
syms   g
omega=1.0;
D = 1.0;
n=15;
I1=eye(n);
I2=eye(2);
matdimension= n-1;
tempvector = 0:1:matdimension;
tempvector = sqrt(tempvector);
tempmatrix = diag(tempvector);
anni= circshift(tempmatrix,-1);
crea = anni';
sc=(crea)^2;
sanni=(anni)^2;
num=crea*anni;
c=crea+anni;
d=sc+sanni;
sigx=[0,1;1,0];
sigy=[0,-1i;1i,0];
sigz=[1,0; 0,-1];
sigp=(1/2)*(sigx+1i.*sigy);
sigm=(1/2)*(sigx -1i.*sigy);
g=0:0.01:2.0;
for i = 1:length(g)
    
       A= omega.*kron(I2,num) + (D./2).* kron(sigz,I1) + g(i).*kron(sigx,c); 
      
      [~,v]=eig(A);
      
    
   
end
%plot(g,p1,'r',g,p2,'r',g,p3,'r',g,p4,'r',g,p5,'r')
%ax = gca;
%set(gca,'XMinorTick','on','YMinorTick','on')

Best Answer

Using sort function, you can sort the elements of matrix in ascending order.
clc;
close all
clear
syms   g
omega=1.0;
D = 1.0;
n=15;
I1=eye(n);
I2=eye(2);
matdimension= n-1;
tempvector = 0:1:matdimension;
tempvector = sqrt(tempvector);
tempmatrix = diag(tempvector);
anni= circshift(tempmatrix,-1);
crea = anni';
sc=(crea)^2;
sanni=(anni)^2;
num=crea*anni;
c=crea+anni;
d=sc+sanni;
sigx=[0,1;1,0];
sigy=[0,-1i;1i,0];
sigz=[1,0; 0,-1];
sigp=(1/2)*(sigx+1i.*sigy);
sigm=(1/2)*(sigx -1i.*sigy);
g=0:0.01:2.0;
for i = 1:length(g)
    
       A= omega.*kron(I2,num) + (D./2).* kron(sigz,I1) + g(i).*kron(sigx,c); 
      
      [~,v]=eig(A);
      V=diag(v);
      Vsort = sort(V);
      Vsort(1)   % minimum eigenvalue
      Vsort(1:5)   % First five minimum eigenvalues
end
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