cordic.m

算超越函数的cordic算法的matlab程序

% function [angle]=cordic(xi,yi);
%                     % Initialitation
%     x = xi
%     y = yi
%     z = 0
%     d = 1;
%     zantes = 0;
%     a = 0;          % Iterative factor
% 	K = 0.6073;     %K Factor
%    % x = K*x;
% while a < 11        % Really only takes a half of this value get an 0.001 of error
%                     % in cosine and sine values.
%      if y >=0
%         d=-1;
%     else
%         d=1;
%      end
%                      %This function is used to get the +1,-1 value, the sing function don?t
%                      %perform d=1 if z=0.
%     xantes=x;
%      x=xantes-(y*d*(1/2^a))
%       y=y+(xantes*d*(1/2^a))
%    z=z-(d*(1024*atan(1/2^a)))
% 
%     a=a+1;
% end
% 
% % cosine = x;
% % sine = y;
% angle=z;


function [z0]=cordic(xi,yi,angle);
                    % Initialitation
    x = xi;
    y = yi;
    z = angle;
    d = 1;
    zantes = 0;
    a = 0;          % Iterative factor
	K = 0.6073;     %K Factor
    %x = K*x;
while a < 11      % Really only takes a half of this value get an 0.001 of error
                    % in cosine and sine values.
     if z >=0
        d=1;
     else
        d=-1;
     end
                     %This function is used to get the +1,-1 value, the sing function don?t
                    % perform d=1 if z=0.
    xantes=x;
     x=xantes-(y*d*(1/2^a))
      y=y+(xantes*d*(1/2^a))
   z=z-(d*(atan(1/2^a)))

    a=a+1;
end

% cosine = x;
% sine = y;
 K*x
 K*y
z0=z;