Can you please find the error in the matlab code below? It generates natural frequencies correctly, but there is an error in modal shapes

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Can you please find the error in the matlab code below? It generates natural frequencies correctly, but there is an error in modal shapes.

modal shapes vector's answer = [1,1,1; 0.647, -0.601, -2.584; 0.301, -0.676.2.484] (You can check according to this answer.)

% program to get normalized vectors and eigen values

clc;

close all;

m=[1 0 0;0 1.5 0;0 0 2];

disp(' mass matrix')

m

%you can give stiffness matrix

% disp(' stiffness matrix')

k=[600 -600 0;-600 1800 -1200;0 -1200 3000];

% k

% a=inv(k);

% or you can given flexibility matrix directly

a=[.75 .5 .25;.5 1 .5;.25 .5 .75];

disp(' flexibility matrix')

a

c=a*m;

[ms,ns]=size(m);

%eigen values and eigen vectors

[V,D]=eig(k,m);

for i=1:ms

e(i)=1/D(i,i);

end

Qh=max(e)+0.001;

Ql=0;

for i=1:ms

for j=1:ms

if e(j) > Ql && e(j) < Qh

kk=j;

Qh=e(j);

else

end

end

Ql=Qh;

Qh=max(e)+0.001;

om1(i)=e(kk);

omega(i)=1/sqrt(e(kk));

for l=1:ms

p1(l,i)=V(l,kk);

end

end

%Normalizing the mode shape

L=p1'*m*p1;

L1=p1'*k*p1;

%develop modal matrix

for i=1:ms

for j=1:ms

p(i,j)=p1(i,j)/sqrt(L(j,j));

end

end

disp(' Natural frequencies in rad/sec')

disp(omega)

disp(' normalized modal vector')

disp(p)

p'*m*p

p'*k*p