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diff --git a/260/CH5/EX5.13/5_13.sce b/260/CH5/EX5.13/5_13.sce
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+//Eg-5.13
+//pg-250
+
+clear
+clc
+
+A=[0 1.5 1;1.5 0 0.5;1 0.5 0];
+iter=1;
+imax=100;
+sig2=0;
+S=sum(A.^2);
+T=eye(3,3);
+
+//A(1,1)=A(2,2)=A(3,3),,,so in this case sinalp=cosalp=(1/2)^.5
+while sig2~=S&iter<imax
+//for i=1,j=2
+sigma=sum(diag(A).^2);
+cosalp=(1/2)^.5;
+sinalp=(1/2)^.5;
+U=[cosalp sinalp 0;sinalp -cosalp 0;0 0 1];
+
+//for i=1,j=3
+A1=inv(U)*A*U;
+
+q=abs(A1(1,1)-A1(3,3));
+p=2*A1(1,3)*q/(A1(1,1)-A1(3,3));
+spq=(p^2+q^2)^.5;
+cosalp=((1+q/spq)/2)^.5;
+sinalp=p/(2*cosalp*spq);
+U1=[cosalp 0 sinalp;0 1 0;sinalp 0 -cosalp];
+
+
+//for i=2,j=3
+A2=inv(U1)*A1*U1;
+
+q=abs(A2(2,2)-A2(3,3));
+p=2*A2(2,3)*q/(A2(2,2)-A2(3,3));
+spq=(p^2+q^2)^.5;
+cosalp=((1+q/spq)/2)^.5;
+sinalp=p/(2*cosalp*spq);
+U2=[1 0 0 ;0 cosalp sinalp;0 sinalp -cosalp];
+
+A3=inv(U2)*A2*U2;
+
+sig2=sum(diag(A3.^2));
+iter=iter+1;
+T=T*U*U1*U2;
+end
+printf('Note that the eigen values are in a different order from that on the text book and the part B is printed first and then the part A\n')
+disp(A)
+disp("eigen values")
+disp(diag(A3))
+disp("eigen vectors are columns of the following matrix")
+disp(T)
+
+
+B=[1 8 7 6;8 7 3 4;7 3 2 1;6 4 1 5];
+[v,d]=spec(B);
+disp(B)
+disp("eigen values")
+disp(d)
+disp("eigen vectors are columns of the following matrix")
+disp(v)
+
+