package chase.s2.net; import java.util.*; public class SelfOrganizingMap { protected SelfOrganizedNode[] nodes; protected SelfOrganizedNode bmu; protected int[] lattice; protected int statBinIndexes; protected int weights; protected int timeIndex = 1; private Queue<Update> updateQueue = new LinkedList<Update>(); private Update nextUpdate = null; /** * Creates a self organizing map with a lattice size, stat indexes and * number of node weights as stated. * @param lattice - An array of integers, designating a shape of the lattice * @param statIndexes - number of indexes in output array * @param weights - the number of weights found in a node */ public SelfOrganizingMap(int[] lattice, int statIndexes, int weights) { if(lattice.length < 1) throw new RuntimeException("Lattice requires atleast 1 dimension."); statBinIndexes = statIndexes; this.lattice = lattice; this.weights = weights; int latticeSize = 1; for(int i=0; i<lattice.length; i++) { latticeSize *= lattice[i]; // if(lattice[i] > maxLatticeDim) { // maxLatticeDim = lattice[i]; // } //end if } //end for nodes = new SelfOrganizedNode[latticeSize]; int[] vector = new int[lattice.length]; for(int i=0; i<latticeSize; i++) { nodes[i] = new SelfOrganizedNode(vector, this); initialize(nodes[i], vector); vector[0]++; for(int j=1; j<lattice.length; j++) { if(vector[j-1] >= lattice[j-1]) { vector[j-1] = 0; vector[j]++; } //end if } //end for } //end for } //Notice: In desperate need of a better initialization! private void initialize(SelfOrganizedNode n, int[] position) { for(int i=0; i<weights; i++) n.weights[i] = Math.random(); } public void updateMap(double[] input, int index) { timeIndex++; bmu = getBMU(input); for(int i=0; i<size();i++) { nodes[i].update(input, index); } } public int size() { return nodes.length; } public void addUpdate(double[] input, int index) { updateQueue.offer(new Update(input,index)); } public void distributeUpdate(int num) { if((nextUpdate == null || nextUpdate.startNode > size()) && !updateQueue.isEmpty()) { nextUpdate = updateQueue.poll(); bmu = getBMU(nextUpdate.weights); timeIndex++; } if(nextUpdate == null) return; for(int i=nextUpdate.startNode; i<size() && i < (nextUpdate.startNode + num); i++) { nodes[i].update(nextUpdate.weights, nextUpdate.index); nextUpdate.startNode++; } } public SelfOrganizedNode getBMU(double[] input) { int bmu = 0; double smallestDifference = Double.POSITIVE_INFINITY; //there is no faster way as the data in the nodes changes constantly for(int i=0; i<size(); i++) { double difference = nodes[i].difference(input); //small shortcut, as we need every ounce of speed if(difference < 0.002) return nodes[i]; if(difference < smallestDifference) { bmu = i; smallestDifference = difference; } } return nodes[bmu]; } private class Update { public double[] weights; public int index; public int startNode; public Update(double w[], int i) { weights = w; index = i; startNode = 0; } } } public class SelfOrganizedNode { protected SelfOrganizingMap map; protected int position[]; protected double weights[]; public float statBin[]; protected SelfOrganizedNode(int[] latticePosition, SelfOrganizingMap parent) { position = latticePosition.clone(); map = parent; statBin = new float[map.statBinIndexes]; weights = new double[map.weights]; } public void update(double[] input, int index) { double distance = distance(map.bmu); double variance = Math.min(2,Math.log(.2*map.timeIndex+1)+.25); double neighborhood = Math.exp(-(variance*variance*distance*distance)/2.0); //double limiter = Math.max(Math.exp(-(map.timeIndex/1000)),.75); if(neighborhood < 0.001) return; for(int i=0; i < map.weights; i++) { weights[i] += neighborhood*(input[i] - weights[i]); } for(int i=0; i<map.statBinIndexes; i++) { int diff = Math.abs(index - i); float stat = (float)Math.exp(-(.7*.7*diff*diff)/2.0); statBin[i] += neighborhood*stat; } } protected float distance(SelfOrganizedNode n) { return distance(position, n.position); } protected double difference(double[] input) { return distance(weights, input); } public static final float distance(int[] p, int[] q) { float k, d = 0; for(int i=0; i<p.length; i++) { d += (k=((float)p[i]-(float)q[i]))*k; } return d; } public static final double distance(double[] p, double[] q) { if(p == null || q == null) return Double.POSITIVE_INFINITY; double k, d = 0; for(int i=0; i<p.length; i++) { d += (k=(p[i]-q[i]))*k; } return d; } }
Its still not running 100% when I plug it into my old prototype gun, but mostly cause I think it uses much more well formed code. ;) --Chase-san