Java tutorial
/* * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ /** * WekaExtractArray.java * Copyright (C) 2010-2016 University of Waikato, Hamilton, New Zealand */ package adams.flow.transformer; import weka.core.Instances; import adams.core.Index; import adams.core.QuickInfoHelper; import adams.data.spreadsheet.Cell; import adams.data.spreadsheet.SpreadSheet; import adams.flow.core.Token; /** <!-- globalinfo-start --> * Extracts a column or row of data from a weka.core.Instances or SpreadSheet object.<br> * Only numeric columns can be returned. In case of row-retrieval, the value of the internal format of the weka.core.Instance object is returned; for SpreadSheet object it is attempted to convert the cell content to double (null values might get returned!). * <br><br> <!-- globalinfo-end --> * <!-- flow-summary-start --> * Input/output:<br> * - accepts:<br> * weka.core.Instances<br> * adams.core.io.SpreadSheet<br> * - generates:<br> * java.lang.Double[]<br> * <br><br> <!-- flow-summary-end --> * <!-- options-start --> * Valid options are: <br><br> * * <pre>-D <int> (property: debugLevel) * The greater the number the more additional info the scheme may output to * the console (0 = off). * default: 0 * minimum: 0 * </pre> * * <pre>-name <java.lang.String> (property: name) * The name of the actor. * default: ExtractArray * </pre> * * <pre>-annotation <adams.core.base.BaseText> (property: annotations) * The annotations to attach to this actor. * default: * </pre> * * <pre>-skip (property: skip) * If set to true, transformation is skipped and the input token is just forwarded * as it is. * </pre> * * <pre>-stop-flow-on-error (property: stopFlowOnError) * If set to true, the flow gets stopped in case this actor encounters an error; * useful for critical actors. * </pre> * * <pre>-type <COLUMN|ROW> (property: type) * The type of extraction to perform, row or column. * default: COLUMN * </pre> * * <pre>-index <java.lang.String> (property: index) * The index of the row/column to extract. * default: first * </pre> * <!-- options-end --> * * @author fracpete (fracpete at waikato dot ac dot nz) * @version $Revision$ */ public class WekaExtractArray extends AbstractTransformer { /** for serialization. */ private static final long serialVersionUID = -3989993009528522476L; /** * The type of extraction to perform. * * @author fracpete (fracpete at waikato dot ac dot nz) * @version $Revision$ */ public enum ExtractionType { /** column. */ COLUMN, /** row. */ ROW } /** the type of extraction. */ protected ExtractionType m_Type; /** the index of the row/column to extract. */ protected Index m_Index; /** * Returns a string describing the object. * * @return a description suitable for displaying in the gui */ @Override public String globalInfo() { return "Extracts a column or row of data from a weka.core.Instances or " + "SpreadSheet object.\n" + "Only numeric columns can be returned. In case of row-retrieval, " + "the value of the internal format of the weka.core.Instance object " + "is returned; for SpreadSheet object it is attempted to convert the " + "cell content to double (null values might get returned!)."; } /** * Adds options to the internal list of options. */ @Override public void defineOptions() { super.defineOptions(); m_OptionManager.add("type", "type", ExtractionType.COLUMN); m_OptionManager.add("index", "index", new Index(Index.FIRST)); } /** * Initializes the member variables. */ @Override protected void initialize() { super.initialize(); m_Index = new Index(); } /** * Returns a quick info about the actor, which will be displayed in the GUI. * * @return null if no info available, otherwise short string */ @Override public String getQuickInfo() { String result; result = QuickInfoHelper.toString(this, "type", m_Type); result += QuickInfoHelper.toString(this, "index", m_Index, ": "); return result; } /** * Sets the type of extraction to perform. * * @param value the type */ public void setType(ExtractionType value) { m_Type = value; reset(); } /** * Returns the type of extraction to perform. * * @return the type */ public ExtractionType getType() { return m_Type; } /** * Returns the tip text for this property. * * @return tip text for this property suitable for * displaying in the GUI or for listing the options. */ public String typeTipText() { return "The type of extraction to perform, row or column."; } /** * Sets the type of extraction to perform. * * @param value the type */ public void setIndex(Index value) { m_Index = value; reset(); } /** * Returns the type of extraction to perform. * * @return the type */ public Index getIndex() { return m_Index; } /** * Returns the tip text for this property. * * @return tip text for this property suitable for * displaying in the GUI or for listing the options. */ public String indexTipText() { return "The index of the row/column to extract."; } /** * Returns the class that the consumer accepts. * * @return <!-- flow-accepts-start -->weka.core.Instances.class, adams.core.io.SpreadSheet.class<!-- flow-accepts-end --> */ public Class[] accepts() { return new Class[] { Instances.class, SpreadSheet.class }; } /** * Returns the class of objects that it generates. * * @return <!-- flow-generates-start -->java.lang.Double[].class<!-- flow-generates-end --> */ public Class[] generates() { return new Class[] { Double[].class }; } /** * Executes the flow item. * * @return null if everything is fine, otherwise error message */ @Override protected String doExecute() { String result; Double[] array; Instances inst; SpreadSheet sheet; int i; int index; Cell cell; result = null; array = null; if (m_InputToken.getPayload() instanceof Instances) { inst = (Instances) m_InputToken.getPayload(); if (m_Type == ExtractionType.COLUMN) m_Index.setMax(inst.numAttributes()); else m_Index.setMax(inst.numInstances()); index = m_Index.getIntIndex(); if (index == -1) result = "Invalid index: " + m_Index + " (max=" + m_Index.getMax() + ")"; else if ((m_Type == ExtractionType.COLUMN) && !inst.attribute(index).isNumeric()) result = "Column " + m_Index + " is not numeric!"; if (result == null) { if (m_Type == ExtractionType.COLUMN) { array = new Double[inst.numInstances()]; for (i = 0; i < array.length; i++) array[i] = inst.instance(i).value(index); } else { array = new Double[inst.numAttributes()]; for (i = 0; i < array.length; i++) array[i] = inst.instance(index).value(i); } } } else { sheet = (SpreadSheet) m_InputToken.getPayload(); if (m_Type == ExtractionType.COLUMN) m_Index.setMax(sheet.getColumnCount()); else m_Index.setMax(sheet.getRowCount()); index = m_Index.getIntIndex(); if (index == -1) result = "Invalid index: " + m_Index + " (max=" + m_Index.getMax() + ")"; else if ((m_Type == ExtractionType.COLUMN) && !sheet.isNumeric(index, true)) result = "Column " + m_Index + " is not numeric!"; if (result == null) { if (m_Type == ExtractionType.COLUMN) { array = new Double[sheet.getRowCount()]; for (i = 0; i < array.length; i++) { cell = sheet.getCell(i, index); if ((cell != null) && !cell.isMissing()) array[i] = cell.toDouble(); } } else { array = new Double[sheet.getColumnCount()]; for (i = 0; i < array.length; i++) { cell = sheet.getCell(index, i); if ((cell != null) && !cell.isMissing()) array[i] = cell.toDouble(); } } } } if (array != null) m_OutputToken = new Token(array); return result; } }