Method convergenceStep

JSAT/src/jsat/clustering/MeanShift.java:317–345

Computes the meanShift of the point at the given index, and then updates the vector array to indicate the movement towards the mode for the data point. @param xit the array of the current data point's positions @param i the index of the data point being considered @param converged the array used to

(final Vec[] xit, int i, final boolean[] converged, final int[] designations, final Vec scratch, final KernelFunction k)

     * @param k the kernel function to use
     */
    private void convergenceStep(final Vec[] xit, int i, final boolean[] converged, final int[] designations, final Vec scratch, final KernelFunction k)
    {
        double denom = 0.0;
        Vec xCur = xit[i];
        List<? extends VecPaired<VecPaired<Vec, Integer>, Double>> contrib = mkde.getNearbyRaw(xCur);
        
        if(contrib.size() == 1)
        {
            //If a point has no neighbors, it can not shift, and is its own mdoe - so we mark it noise
            converged[i] = true;
            designations[i] = -1;
        }
        else
        {
            scratch.zeroOut();
            for(VecPaired<VecPaired<Vec, Integer>, Double> v : contrib)
            {
                double g = - k.kPrime(v.getPair());
                denom += g;
                scratch.mutableAdd(g, v);
            }
            scratch.mutableDivide(denom);

            if( Math.abs(scratch.pNormDist(2, xCur)) < 1e-5)
                converged[i] = true;

            scratch.copyTo(xCur);
        }
    }

    @Override
    public MeanShift clone()