twiddles.m

TigerSharc TS201 32-bit floating point FFT routine

function [id] = twiddles(name_file, N)

   for k=1:N/2
        twid(k)=complex(cos(2*pi*(k-1)/N), -sin(2*pi*(k-1)/N));
        re = real(twid(k));
        im = imag(twid(k));

        if re==1
            real_twid(k)=2^15-1;
        elseif re>=0
            real_twid(k)=round(2^15*re);
        else
            real_twid(k)=round(2^16+2^15*re);
        end;
        if im==1
            imag_twid(k)=2^15-1;
        elseif im>=0
            imag_twid(k)=round(2^15*im);
        else
            imag_twid(k)=round(2^16+2^15*im);
        end;



   end;

       fin = fopen(name_file, 'wt');
           for k=1:N/2
               fprintf(fin, '0x%04x%04x\n', imag_twid(k), real_twid(k));
           end;
       fclose(fin);