xuyang1706 commented on a change in pull request #8631: [FLINK-12745][ml] add sparse and dense vector class, and dense matrix class with basic operations. URL: https://github.com/apache/flink/pull/8631#discussion_r296091344
########## File path: flink-ml-parent/flink-ml-lib/src/main/java/org/apache/flink/ml/common/matrix/DenseMatrix.java ########## @@ -0,0 +1,751 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.flink.ml.common.matrix; + +import java.io.Serializable; +import java.util.Arrays; + +/** + * Dense Matrix. + */ +public class DenseMatrix implements Serializable { + /* ------------------------ + Class variables + * ------------------------ */ + + /** + * Row and column dimensions. + */ + int m, n; + + /** + * Array for internal storage of elements. + * <p> + * The matrix data is stored in column major format internally. + */ + double[] data; + + /* --------------------------------------------------- + * Constructors + * --------------------------------------------------- */ + + /** + * Construct an empty matrix. + */ + public DenseMatrix() { + } + + /** + * Construct an m-by-n matrix of zeros. + * + * @param m Number of rows. + * @param n Number of colums. + */ + public DenseMatrix(int m, int n) { + this.m = m; + this.n = n; + this.data = new double[m * n]; + } + + /** + * Construct a matrix from a 1-D array. The data in the array should organize + * in row major. + * + * @param m Number of rows. + * @param n Number of cols. + * @param data One-dimensional array of doubles. + */ + public DenseMatrix(int m, int n, double[] data) { + this(m, n, data, true); + } + + /** + * Construct a matrix from a 1-D array. The data in the array is organized + * in column major or in row major, which is specified by parameter 'inRowMajor' + * + * @param m Number of rows. + * @param n Number of cols. + * @param data One-dimensional array of doubles. + * @param inRowMajor Whether the matrix in 'data' is in row major format. + */ + public DenseMatrix(int m, int n, double[] data, boolean inRowMajor) { + assert (data.length == m * n); + this.m = m; + this.n = n; + if (inRowMajor) { + this.data = new double[m * n]; + for (int i = 0; i < m; i++) { + for (int j = 0; j < n; j++) { + this.set(i, j, data[i * n + j]); + } + } + } else { + this.data = data.clone(); + } + } + + /** + * Construct a matrix from a 2-D array. + * + * @param matA Two-dimensional array of doubles. + * @throws IllegalArgumentException All rows must have the same size + */ + public DenseMatrix(double[][] matA) { + this.m = matA.length; + this.n = matA[0].length; + for (int i = 0; i < m; i++) { + if (matA[i].length != n) { + throw new IllegalArgumentException("All rows must have the same size."); + } + } + this.data = new double[m * n]; + for (int i = 0; i < m; i++) { + for (int j = 0; j < n; j++) { + this.set(i, j, matA[i][j]); + } + } + } + + /** + * Construct a matrix with provided data buffer. + * This is for internal use only, so it is package private. + * + * @param m Number of rows. + * @param n Number of cols. + * @param data One-dimensional array of doubles. + */ + public static DenseMatrix fromDataBuffer(int m, int n, double[] data) { + assert m * n == data.length; + DenseMatrix matA = new DenseMatrix(); + matA.m = m; + matA.n = n; + matA.data = data; + return matA; + } + + /* --------------------------------------------------- + * Handy methods for creating matrix + * --------------------------------------------------- */ + + /** + * Create an identity matrix. + * + * @param n + * @return + */ + public static DenseMatrix eye(int n) { + return eye(n, n); + } + + /** + * Create a identity matrix. + * + * @param m + * @param n + * @return + */ + public static DenseMatrix eye(int m, int n) { + DenseMatrix matM = new DenseMatrix(m, n); + int mn = Math.min(m, n); + for (int i = 0; i < mn; i++) { + matM.data[i * n + i] = 1.0; + } + return matM; + } + + /** + * Create a zero matrix. + * + * @param m + * @param n + * @return + */ + public static DenseMatrix zeros(int m, int n) { + return new DenseMatrix(m, n); + } + + /** + * Create a matrix will all elements 1. + * + * @param m + * @param n + * @return + */ + public static DenseMatrix ones(int m, int n) { + DenseMatrix mat = new DenseMatrix(m, n); + Arrays.fill(mat.data, 1.); + return mat; + } + + /** + * Create a random matrix. + * + * @param m + * @param n + * @return + */ + public static DenseMatrix rand(int m, int n) { + DenseMatrix mat = new DenseMatrix(m, n); + for (int i = 0; i < m; i++) { + for (int j = 0; j < n; j++) { + mat.set(i, j, Math.random()); + } + } + return mat; + } + + /** + * Create a random symmetric matrix. + * + * @param n + * @return + */ + public static DenseMatrix randSymmetric(int n) { + DenseMatrix mat = new DenseMatrix(n, n); + for (int i = 0; i < n; i++) { + for (int j = i; j < n; j++) { + double r = Math.random(); + mat.set(i, j, r); + if (i != j) { + mat.set(j, i, r); + } + } + } + return mat; + } + + /* --------------------------------------------------- + * Methods for accessing matrix data + * --------------------------------------------------- */ + + /** + * C := A .* B . + */ + public static DenseMatrix elementWiseProduct(DenseMatrix matA, DenseMatrix matB) { Review comment: OK, moved to DenseMatrixUtil. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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