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function q = graeffe(A,eps)
n = length(A)-1;
x = poly(0,'x');
for(i = 1:n)
X(i) = x^(n+1-i);
end
X(n+1) = 1;
//disp(X)
//converting this polynomial into standard one where the coefficient of highest order term is 1
A = A/A(1);
p = A*X;
printf('The given polynomial is\n')
disp(p)
n = length(X)-1;
j = 1;
a(j,1) = A(j,2);
a(j,2) = abs(A(j,3)/A(j,2));
//eps = 0.000001;
err = 1;
printf('\nIteration no. error eps\n')
while(err>eps)
A(j,1) = 1;
for(i = 2:n+1)
S = 0;
for(k = 1:i-1)
if(i-1+k>n)
A(j,i+k) = 0;
end
S = S+ (-1)^k*A(j,i+k)*A(j,i-k);
end
A(j+1,i) = (-1)^(i-1)*(A(j,i)^2 + 2*S);
end
a(j+1,1) = abs(A(j+1,2))^(1/2^j);
for(i = 3:n+1)
a(j+1,i-1) = (abs(A(j+1,i)/A(j+1,i-1)))^(1/2^j);
end
b = abs(a);
err = abs((sum(b(j+1,:)) - sum(b(j,:)))/sum(b(j,:)));
printf(' %d %f %f\n',j,err,eps)
j = j+1;
end
printf('\nThe roots are \n')
for(i = 1:n)
printf(' %f\n',a(j,i))
end
q = a(j,:);
endfunction
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