bundles/org.simantics.history/src/org/simantics/history/util/WeightedMedianBinding.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2011 Association for Decentralized Information Management in
   3  * Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.history.util;
  13
  14 import java.util.Iterator;
  15
  16 import org.simantics.databoard.Bindings;
  17 import org.simantics.databoard.binding.ArrayBinding;
  18 import org.simantics.databoard.binding.error.BindingException;
  19 import org.simantics.databoard.type.ArrayType;
  20
  21 /**
  22  * This class binds median class to as an array(double) where every second value
  23  * represents value and odd weight.
  24  */
  25 public class WeightedMedianBinding extends ArrayBinding {
  26
  27         public WeightedMedianBinding() {
  28                 super(new ArrayType(Bindings.DOUBLE.type()), Bindings.DOUBLE);
  29         }
  30
  31         @Override
  32         public Object create() {
  33                 return new WeightedMedian();
  34         }
  35
  36         @Override
  37         public Object create(int length, Iterator<Object> it) throws BindingException {
  38                 WeightedMedian result = new WeightedMedian( length );
  39                 int count = length/2;
  40                 WeightedMedian.Item[] items = new WeightedMedian.Item[count];
  41                 int index = 0;
  42                 double value=0.0, weight=0.0;
  43                 while (it.hasNext()) {
  44                         double d = (Double) it.next();
  45                         if ( index%2==0 ) {
  46                                 value = d;
  47                         } else {
  48                                 weight = d;
  49                                 WeightedMedian.Item i = new WeightedMedian.Item(weight, value);
  50                                 items[ index/2 ] = i;
  51                         }
  52                         index++;
  53                 }
  54                 if ( count>0 ) {
  55                         items[0].next = items[1];
  56                         items[count-1].prev = items[count-2];
  57                 }
  58                 for (index=1; index<count-1; index++) {
  59                         items[index].next = items[index+1];
  60                         items[index].prev = items[index-1];
  61                 }
  62                 result.median = items[count/2];
  63                 result.itemCount = count;
  64                 return result;
  65         }
  66
  67         @Override
  68         public Object create(Object[] array) throws BindingException {
  69                 int count = array.length/2;
  70                 WeightedMedian result = new WeightedMedian();
  71                 WeightedMedian.Item[] items = new WeightedMedian.Item[count];
  72                 double value=0.0, weight=0.0;
  73                 for (int index=0; index<array.length; index++) {
  74                         double d = (Double) array[index];
  75                         if ( index%2==0 ) {
  76                                 value = d;
  77                         } else {
  78                                 weight = d;
  79                                 WeightedMedian.Item i = new WeightedMedian.Item(weight, value);
  80                                 items[ index/2 ] = i;
  81                         }
  82                         index++;
  83                 }
  84                 if ( count>0 ) {
  85                         items[0].next = items[1];
  86                         items[count-1].prev = items[count-2];
  87                 }
  88                 for (int index=1; index<count-1; index++) {
  89                         items[index].next = items[index+1];
  90                         items[index].prev = items[index-1];
  91                 }
  92                 result.median = items[count/2];
  93                 result.itemCount = count;
  94                 return result;
  95         }
  96
  97         @Override
  98         public void add(Object array, int index, Object element) throws BindingException, IndexOutOfBoundsException {
  99                 throw new BindingException("not implemented");
 100         }
 101
 102         @Override
 103         public void remove(Object array, int index, int count) throws BindingException {
 104                 throw new BindingException("not implemented");
 105         }
 106
 107         @Override
 108         public Object get(Object array, int index) throws BindingException {
 109                 int pos = index/2;
 110                 WeightedMedian median = (WeightedMedian) array;
 111                 int c = median.itemCount*2;
 112                 if ( index<0 || index>=c ) throw new BindingException("Index "+index+" out of bounds "+c);
 113                 WeightedMedian.Item i = median.head();
 114                 for (int ix=1; ix<pos; ix++) i = i.next;
 115                 return index%2==0?i.value:i.weight;
 116         }
 117
 118         @Override
 119         public void getAll(Object array, Object[] result) throws BindingException {
 120                 int c = size( array );
 121                 if (result.length<c) throw new BindingException("Array too small");
 122                 WeightedMedian median = (WeightedMedian) array;
 123                 int ix = 0;
 124                 WeightedMedian.Item i = median.head();
 125                 while (i != null) {
 126                         result[ix] = i.value; ix++;
 127                         result[ix] = i.weight; ix++;
 128                         i = i.next;
 129                 }
 130         }
 131
 132         @Override
 133         public void set(Object array, int index, Object value) throws BindingException {
 134                 remove(array, index);
 135                 add(array, value);
 136         }
 137
 138         @Override
 139         public void setSize(Object array, int newSize) throws BindingException {
 140                 int size = size(array);
 141                 if (size<newSize) newSize = size;
 142                 remove( array, size-newSize, newSize);
 143         }
 144
 145         @Override
 146         public int size(Object array) throws BindingException {
 147                 WeightedMedian median = (WeightedMedian) array;
 148                 return median.itemCount*2;
 149         }
 150
 151         @Override
 152         public boolean isInstance(Object obj) {
 153                 return obj instanceof WeightedMedian;
 154         }
 155
 156         @Override
 157         public boolean isResizable() {
 158                 return true;
 159         }
 160
 161 }
 162
 163