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function [output]=bin2frac(a,ibits,fbits);

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

%           a=array to be converted to real numbers

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

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

%       This returns a real number in [output]

%    **NOTE**   This is not idiot proof, and will cause problem           s if th  e number is bigger

%                tha n bits specified.  It also assumes 2's complement form

%code to convert back from signed to sign/magnitude

unin=a;

bitsign=1;

if unin(ibits+fbits)==1

    bitsign=-1;

    testbit=1;

    for k=1:(ibits+fbits),

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

            testbit=0;

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

            unin(k)=1;

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

            unin(k)=0;

         end

     end

end

temp=0;

bitvalue=pow2(ibits-2);

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

    temp=temp+unin(k)*bitvalue;

    bitvalue=bitvalue/2;

end

output=temp*bitsign;