function y=quadraticFormula0(a,b,c)
% Roots of a quadratic equation:
% STRAIGHTFORWARD usage of the quadratic formula
% NO attention is paid to minimize rooundoff error,
% overflow and unnecessary underflow.
% The coefficients must all be real.
% However the roots may be complex.
% K. Ming Leung, 01/09/03

if (a~=0)
    d=b*b-4*a*c;
    a2=2*a;
    if (d>0)         % both roots are real
        ds=sqrt(d);
        x1=(-b+ds)/a2;
        x2=-(b+ds)/a2;
    elseif (d<0)     % pair of complex roots
        ds=sqrt(-d);
        r1=-b/a2;
        r2=ds/a2;
        x1=r1+i*r2;
        x2=conj(x1);
    else
        x1=-b/a2; x2=x1;
    end;
else                     % for a=0
    x1=-c/b; x2=Inf;
end
y=[x1 x2];