protected double kEvalSum(Vec y)
    {
        if (alphas == null)
            throw new RuntimeException("alphas have not been set");

        return kernel.evalSum(vecs, accelCache, alphas, y, 0, alphas.length);
    }
protected double kEvalSum ( Vec y ) { if ( alphas == null ) throw new RuntimeException ( "alphas have not been set" ) ; return kernel . evalSum ( vecs , accelCache , alphas , y , 0 , alphas . length ) ; }
Performs a summation of the form <br>
<big>&#8721;</big> &alpha;<sub>i</sub> k(x<sub>i</sub>, y) <br>
for each support vector and associated alpha value currently stored in
the support vector machine. It is not necessary to call
{@link #setAlphas(double[]) } before calling this, but kernel evaluations
may be slower if this is not done.
@param y the vector to perform the kernel product sum against
@return the sum of the scaled kernel products