/**
* <summary> The calculateRMinusY method creates a new {@link java.util.Vector} with given Instance, then it multiplies given
* input Vector with given weights Matrix. After normalizing the output, it return the difference between the newly created
* Vector and normalized output.</summary>
*
* <param name="instance">Instance is used to get class labels.</param>
* <param name="input"> Vector to multiply weights.</param>
* <param name="weights"> Matrix of weights/</param>
* <returns>Difference between newly created Vector and normalized output.</returns>
*/
protected Vector CalculateRMinusY(Instance.Instance instance, Vector input, Matrix weights)
{
r = new Vector(K, classLabels.IndexOf(instance.GetClassLabel()), 1.0);
var o = weights.MultiplyWithVectorFromRight(input);
y = NormalizeOutput(o);
return(r.Difference(y));
}