function y = evalRPoly(roots,x,k)%function y = evalRPoly(roots,x,k=1)%Compute the value of a polynomial which is given in terms of its roots.if(nargin<3)    k=1;endy = k(ones(size(x)));roots = roots(~isinf(roots));        % remove roots at infinityfor(i=1:length(roots))    y = y.*(x-roots(i));end