function Y3 = shiftf(X3,c)
% Y3 = shiftf(X3,c)
% X3 is matrix coefficients of
% a polynomial P(x).
% c is a number.
% Result Y3 is  coefficients of P(y+c)

  test=size(X3);
if (size(test)<3)
Y3 = X3;
return
end%if
% Matlab automatically squeezes some results, so we stop here instead of 
% putting the rest of the function into an else clause.
  n=test(3);
  if (n == 1)
    Y3 = X3;
  else
    [Q3,V] = syndivf(X3,c);
    Y3=cat(3,shiftf(Q3,c),V);
% build vector of remainders
  end%if
end%function
% Rutgers teaching code by R. T. Bumby