% SCHEBPOL  symbolic Chebyshev polynomials 
%
function y=schebpol(dig,x,n)
digits(dig);
x=vpa(x);
Tkm1=vpa(1); Tk=x;
for k=2:n
  Tkm2=Tkm1; Tkm1=Tk;
  Tk=vpa(2*x.*Tkm1-Tkm2);
end
y=Tk;
