Subversion Repositories wdsp

function [output]=frac2bin(a,ibits,fbits);

%  [output]=frac2bin(a,ibits, fbits);

%           a= number to be converted

%           ibits=integer part bits, must be an integer >0

%           fbits=number of  fractional bits, must be an integer>=0

%       This returns an array [output] that is the input number

%       in twos  complement form

%        [output] is ibits+fbits long

%    **NOTE**   This is not  idiot proof, and will cause problems if the number is too big

%               for the nu mber of bits specified-1.

if   (a>=0)

      bitsign=1;

    number=a;

else

    bitsign=-1;

    number=(a*-1);

end

ipart=number-rem(number,1);

fpart=rem(number,1);

unout (ibits+fbits)=0;

signedzero=1 ;

if ibits~=1

    for k=(ibits-1):-1:1,

        if ipart>=2^(k-1)

            unout(k+fbits)=1;

            ipart=ipart-2^(k-1);

            signedzero=0;

        end

    end

end

for k=fbits:-1:1,

    fpart=fpart*2;

    if fpart>=1

         unout(k)=1;

        fpart=fpart-1;

        signedzero=0;

    end

end

if (bitsign==-1) & (signedzero==0)

    testbit=1;

    for k=1:(ibits+fbits-1),

        if ((testbit==1) & (unout(k)==      1))

            testbit=0;

        elseif ((testbit==0) & (unout(k)==0))

            unout(k)=1;

        elseif ((testbit==0) & (unout(k)==1))

            unout(k)=0;

        end

    end

    unout(ibits+fbits)=1;

end

output=unout;