function b=miphapol(a)

% Converts the polynomial a into a minimum phase one.
%
% Programmed by: Dimitris Manolakis, 1995
%
%-----------------------------------------------------------
% Copyright 2000, by Dimitris G. Manolakis, Vinay K. Ingle,
% and Stephen M. Kogon.  For use with the book
% "Statistical and Adaptive Signal Processing"
% McGraw-Hill Higher Education.
%-----------------------------------------------------------



c=a(1);
a=a/c;
z=roots(a);

r=abs(z);
theta=angle(z);
N=length(z);

for k=1:N
 
  if r(k)<1 
  else 
    r(k)=1/r(k);
    theta(k)=-theta(k); 
    z(k)=r(k)*cos(theta(k))+sqrt(-1)*r(k)*sin(theta(k));
  end

end
 
b=c*poly(z);