org.numenta.nupic.util.SparseBinaryMatrix Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of htm.java Show documentation
The Java version of Numenta's HTM technology
There is a newer version: 0.6.13
/* ---------------------------------------------------------------------
 * Numenta Platform for Intelligent Computing (NuPIC)
 * Copyright (C) 2014, Numenta, Inc.  Unless you have an agreement
 * with Numenta, Inc., for a separate license for this software code, the
 * following terms and conditions apply:
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero Public License version 3 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero Public License for more details.
 *
 * You should have received a copy of the GNU Affero Public License
 * along with this program.  If not, see http://www.gnu.org/licenses.
 *
 * http://numenta.org/licenses/
 * ---------------------------------------------------------------------
 */

package org.numenta.nupic.util;

import java.lang.reflect.Array;
import java.util.Arrays;

import org.numenta.nupic.model.Persistable;

/**
 * Implementation of a sparse matrix which contains binary integer
 * values only.
 * 
 * @author cogmission
 *
 */
public class SparseBinaryMatrix extends AbstractSparseBinaryMatrix implements Persistable {
    /** keep it simple */
    private static final long serialVersionUID = 1L;
    
    private Object backingArray;

    /**
     * Constructs a new {@code SparseBinaryMatrix} with the specified
     * dimensions (defaults to row major ordering)
     * 
     * @param dimensions    each indexed value is a dimension size
     */
    public SparseBinaryMatrix(int[] dimensions) {
        this(dimensions, false);
    }

    /**
     * Constructs a new {@code SparseBinaryMatrix} with the specified dimensions,
     * allowing the specification of column major ordering if desired. 
     * (defaults to row major ordering)
     * 
     * @param dimensions                each indexed value is a dimension size
     * @param useColumnMajorOrdering    if true, indicates column first iteration, otherwise
     *                                  row first iteration is the default (if false).
     */
    public SparseBinaryMatrix(int[] dimensions, boolean useColumnMajorOrdering) {
        super(dimensions, useColumnMajorOrdering);
        this.backingArray = Array.newInstance(int.class, dimensions);
    }

    /**
     * Called during mutation operations to simultaneously set the value
     * on the backing array dynamically.
     * @param val
     * @param coordinates
     */
    private void back(int val, int... coordinates) {
        ArrayUtils.setValue(this.backingArray, val, coordinates);
        //update true counts
        setTrueCount(coordinates[0], ArrayUtils.aggregateArray(((Object[])this.backingArray)[coordinates[0]]));
    }

    /**
     * Returns the slice specified by the passed in coordinates.
     * The array is returned as an object, therefore it is the caller's
     * responsibility to cast the array to the appropriate dimensions.
     * 
     * @param coordinates	the coordinates which specify the returned array
     * @return	the array specified
     * @throws	IllegalArgumentException if the specified coordinates address
     * 			an actual value instead of the array holding it.
     */
    @Override
    public Object getSlice(int... coordinates) {
        Object slice = ArrayUtils.getValue(this.backingArray, coordinates);
        //Ensure return value is of type Array
        if(!slice.getClass().isArray()) {
            sliceError(coordinates);
        }

        return slice;
    }

    /**
     * Fills the specified results array with the result of the 
     * matrix vector multiplication.
     * 
     * @param inputVector		the right side vector
     * @param results			the results array
     */
    public void rightVecSumAtNZ(int[] inputVector, int[] results) {
        for(int i = 0;i < dimensions[0];i++) {
            int[] slice = (int[])(dimensions.length > 1 ? getSlice(i) : backingArray);
            for(int j = 0;j < slice.length;j++) {
                results[i] += (inputVector[j] * slice[j]);
            }
        }
    }
    
    /**
     * Fills the specified results array with the result of the 
     * matrix vector multiplication.
     * 
     * @param inputVector       the right side vector
     * @param results           the results array
     */
    public void rightVecSumAtNZ(int[] inputVector, int[] results, double stimulusThreshold) {
        for(int i = 0;i < dimensions[0];i++) {
            int[] slice = (int[])(dimensions.length > 1 ? getSlice(i) : backingArray);
            for(int j = 0;j < slice.length;j++) {
                results[i] += (inputVector[j] * slice[j]);
                if(j==slice.length - 1) {
                    results[i] -= results[i] < stimulusThreshold ? results[i] : 0;
                }
            }
        }
    }

    /**
     * Sets the value at the specified index.
     * 
     * @param index     the index the object will occupy
     * @param object    the object to be indexed.
     */
    @Override
    public AbstractSparseBinaryMatrix set(int index, int value) {
        int[] coordinates = computeCoordinates(index);
        return set(value, coordinates);
    }

    /**
     * Sets the value to be indexed at the index
     * computed from the specified coordinates.
     * @param coordinates   the row major coordinates [outer --> ,...,..., inner]
     * @param object        the object to be indexed.
     */
    @Override
    public AbstractSparseBinaryMatrix set(int value, int... coordinates) {
        back(value, coordinates);
        return this;
    }

    /**
     * Sets the specified values at the specified indexes.
     * 
     * @param indexes   indexes of the values to be set
     * @param values    the values to be indexed.
     * 
     * @return this {@code SparseMatrix} implementation
     */
    public AbstractSparseBinaryMatrix set(int[] indexes, int[] values) { 
        for(int i = 0;i < indexes.length;i++) {
            set(indexes[i], values[i]);
        }
        return this;
    }

    /**
     * Clears the true counts prior to a cycle where they're
     * being set
     */
    public void clearStatistics(int row) {
        this.setTrueCount(row, 0);
        int[] slice = (int[])Array.get(backingArray, row);
        Arrays.fill(slice, 0);
    }

    @Override
    public AbstractSparseBinaryMatrix set(int index, Object value) {
        set(index, ((Integer) value).intValue());
        return this;
    }

    @Override
    public Integer get(int index) {
        int[] coordinates = computeCoordinates(index);
        if (coordinates.length == 1) {
            return Array.getInt(this.backingArray, index);
        }
        
        else return (Integer) ArrayUtils.getValue(this.backingArray, coordinates);
    }

    @Override
    public AbstractSparseBinaryMatrix setForTest(int index, int value) {
        ArrayUtils.setValue(this.backingArray, value, computeCoordinates(index));
        return this;
    }
   
}