package lpa;

import java.util.Arrays;

import java.util.HashMap;

import java.util.Map;

public class LPA {

	public static float sigma = 1;

	public static int tag_num = 2;

	public static void main(String[] args) {

		float[][] data = {

				{1,1},

				{1,2},

				{2,1},

				{2,2},

				{4,4},

				{6,6},

				{6,7},

				{7,6},

				{7,7}

		};

		Map<Integer, Integer> tag_map = new HashMap<Integer, Integer>();

		tag_map.put(1, 1);

		tag_map.put(6, 0);

		float[][] weight = new float[data.length][data.length];

		for(int i = 0; i < weight.length; i++) {

			float sum = 0f;

			for(int j = 0; j < weight[i].length; j++) {

				weight[i][j] = (float) Math.exp( - distance(data[i], data[j]) / Math.pow(sigma, 2));

				sum += weight[i][j];

			}

			for(int j = 0; j < weight[i].length; j++) {

				weight[i][j] /= sum;

			}

		}

		System.out.println("=============");

		for(int i = 0; i < weight.length; i++) {

			System.out.println(Arrays.toString(weight[i]));

		}

		System.out.println("=============");

		float[][] tag_matrix = new float[data.length][tag_num];

		for(int i = 0; i < tag_matrix.length; i++) {

			if(tag_map.get(i) != null) {

				tag_matrix[i][tag_map.get(i)] = 1;

			} else {

				float sum = 0;

				for(int j = 0; j < tag_matrix[i].length; j++) {

					tag_matrix[i][j] = (float) Math.random();

					sum += tag_matrix[i][j];

				}

				for(int j = 0; j < tag_matrix[i].length; j++) {

					tag_matrix[i][j] /= sum;

				}

			}

		}

		for(int it = 0; it < 100; it++) {

			for(int i = 0; i < tag_matrix.length; i++) {

				if(tag_map.get(i) != null) {

					continue;

				}

				float all_sum = 0;

				for(int j = 0; j < tag_matrix[i].length; j++) {

					float sum = 0;

					for(int k = 0; k < weight.length; k++) {

						sum += weight[i][k] * tag_matrix[k][j];

					}

					tag_matrix[i][j] = sum;

					all_sum += sum;

				}

				for(int j = 0; j < tag_matrix[i].length; j++) {

					tag_matrix[i][j] /= all_sum;

				}

			}

			System.out.println("=============");

			for(int i = 0; i < tag_matrix.length; i++) {

				System.out.println(Arrays.toString(tag_matrix[i]));

			}

			System.out.println("=============");

		}

	}

	public static float distance(float[] a, float[] b) {

		float dis = 0;

		for(int i = 0; i < a.length; i++) {

			dis = (float) Math.pow(b[i] - a[i], 2);

		}

		return dis;

	}

}