function y = GrayDecoding(x,Nbits);% y = GrayDecoding(x,Nbits);%% returns the systematic Gray code of the Nbit number x.% S Weiss, 10/10/2000% x in [0; 2^Nbits-1]y = 0;dummy = 0;for i = Nbits:-1:1,    A = floor(x/2^(i-1));    if (A==1)	x = x - 2^(i-1);    end;    if (A~=dummy),       y = y+2^(i-1);    end;    dummy = A;       end;