| /* |
| * 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.sysds.runtime.compress; |
| |
| import org.apache.sysds.runtime.compress.utils.DblArray; |
| import org.apache.sysds.runtime.matrix.data.MatrixBlock; |
| |
| /** considers only a subset of row indexes */ |
| public class ReaderColumnSelectionDenseSample extends ReaderColumnSelection { |
| protected MatrixBlock _data; |
| |
| private int[] _sampleIndexes; |
| private int lastIndex = -1; |
| |
| // reusable return |
| private DblArray reusableReturn; |
| private double[] reusableArr; |
| |
| public ReaderColumnSelectionDenseSample(MatrixBlock data, int[] colIndexes, int[] sampleIndexes, |
| CompressionSettings compSettings) { |
| super(colIndexes, -1, compSettings); |
| _data = data; |
| _sampleIndexes = sampleIndexes; |
| reusableArr = new double[colIndexes.length]; |
| reusableReturn = new DblArray(reusableArr); |
| } |
| |
| protected DblArray getNextRow() { |
| if(lastIndex == _sampleIndexes.length - 1) |
| return null; |
| lastIndex++; |
| for(int i = 0; i < _colIndexes.length; i++) { |
| reusableArr[i] = _compSettings.transposeInput ? _data.quickGetValue(_colIndexes[i], |
| _sampleIndexes[lastIndex]) : _data.quickGetValue(_sampleIndexes[lastIndex], _colIndexes[i]); |
| } |
| return reusableReturn; |
| } |
| |
| @Override |
| public int getCurrentRowIndex() { |
| return _sampleIndexes[lastIndex]; |
| } |
| } |