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_r311990014
########## File path: flink-ml-parent/flink-ml-lib/src/main/java/org/apache/flink/ml/common/matrix/BLAS.java ########## @@ -0,0 +1,140 @@ +/* + * 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; + +/** + * A utility class that wraps netlib BLAS and provides some operations on dense matrix + * and dense vector. + */ +public class BLAS { + private static final com.github.fommil.netlib.BLAS BLAS = com.github.fommil.netlib.BLAS.getInstance(); + + /** + * y += a * x . + */ + public static void axpy(double a, double[] x, double[] y) { + BLAS.daxpy(x.length, a, x, 1, y, 1); + } + + /** + * y += a * x . + */ + public static void axpy(double a, DenseVector x, DenseVector y) { + axpy(a, x.getData(), y.getData()); + } + + /** + * x \cdot y . + */ + public static double dot(double[] x, double[] y) { + return BLAS.ddot(x.length, x, 1, y, 1); + } + + /** + * x \cdot y . + */ + public static double dot(DenseVector x, DenseVector y) { + return dot(x.getData(), y.getData()); + } + + /** + * x = x * a . + */ + public static void scal(double a, double[] x) { + BLAS.dscal(x.length, a, x, 1); + } + + /** + * x = x * a . + */ + public static void scal(double a, DenseVector x) { + scal(a, x.getData()); + } + + /** + * || x - y ||^2 . + */ + public static double dsquared(double[] x, double[] y) { + double s = 0.; + for (int i = 0; i < x.length; i++) { + double d = x[i] - y[i]; + s += d * d; + } + return s; + } + + /** + * | x - y | . + */ + public static double dabs(double[] x, double[] y) { + double s = 0.; + for (int i = 0; i < x.length; i++) { + double d = x[i] - y[i]; + s += Math.abs(d); + } + return s; + } + + /** + * C := alpha * A * B + beta * C . + */ + public static void gemm(double alpha, DenseMatrix matA, boolean transA, DenseMatrix matB, boolean transB, + double beta, DenseMatrix matC) { + if (transA) { + assert matA.numCols() == matC.numRows(); Review comment: Thanks for the suggestion. We have added the messages. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
