001/*-
002 *******************************************************************************
003 * Copyright (c) 2011, 2016 Diamond Light Source Ltd.
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the Eclipse Public License v1.0
006 * which accompanies this distribution, and is available at
007 * http://www.eclipse.org/legal/epl-v10.html
008 *
009 * Contributors:
010 *    Peter Chang - initial API and implementation and/or initial documentation
011 *******************************************************************************/
012
013package org.eclipse.january.dataset;
014
015import java.util.ArrayList;
016import java.util.Arrays;
017import java.util.List;
018
019/**
020 * Class to run over an array of integer datasets and return its items
021 */
022public class IntegersIterator extends IndexIterator {
023        final private int[] ishape; // shape of input
024        final private int irank; // rank of input shape
025        final private int[] oshape; // shape of output
026        final private int orank; // rank of output shape
027        private int offset; // offset of index subspace in new position 
028        private int srank; // rank of subspace
029
030        final private IndexIterator it;
031
032        /**
033         * position in input shape
034         */
035        final private int[] ipos;
036        /**
037         * position in output shape
038         */
039        final private int[] opos;
040        final private List<Object> indexes;
041
042        /**
043         * Constructor for an iterator over the items of an array of objects
044         * @param shape of entire data array
045         * @param index an array of integer dataset, boolean dataset, slices or null entries (same as full slices)
046         */
047        public IntegersIterator(final int[] shape, final Object... index) {
048                this(false, shape, index);
049        }
050
051        /**
052         * Constructor for an iterator over the items of an array of objects
053         * @param restrict1D if true, allow only one 1D integer datasets otherwise they must match shape
054         * @param shape of entire data array
055         * @param index an array of integer dataset, boolean dataset, slices or null entries (same as full slices)
056         */
057        public IntegersIterator(final boolean restrict1D, final int[] shape, final Object... index) {
058                ishape = shape.clone();
059                irank = shape.length;
060                if (irank < index.length) {
061                        throw new IllegalArgumentException("Number of index datasets is greater than rank of dataset");
062                }
063                indexes = new ArrayList<Object>();
064                for (Object i : index) {
065                        if (i instanceof BooleanDataset) { // turn boolean datasets into integer ones
066                                for (IntegerDataset id : Comparisons.nonZero((Dataset) i)) {
067                                        indexes.add(id);
068                                }
069                        } else if (i == null || i instanceof Slice) {
070                                indexes.add(i);
071                        } else if (i instanceof IntegerDataset) {
072                                Dataset id = (Dataset) i;
073                                int r = id.getRank();
074                                if (restrict1D && r > 1) {
075                                        throw new IllegalArgumentException("Integer datasets were restricted to zero or one dimensions");
076                                }
077                                if (r == 0) { // avoid zero-rank datasets
078                                        i = id.reshape(1);
079                                }
080                                indexes.add(i);
081                        } else {
082                                throw new IllegalArgumentException("Unsupported object for indexing");
083                        }
084                }
085                if (indexes.size() < irank) { // pad out index list
086                        for (int i = indexes.size(); i < irank; i++) {
087                                indexes.add(null);
088                        }
089                } else if (indexes.size() > irank) {
090                        throw new IllegalArgumentException("Too many indices (a boolean dataset may have too many dimensions)");
091                }
092
093                int ilength = -1;
094                int[] cshape = null;
095                int first = -1; // index of first null or slice after non-null index
096                boolean intact = true;
097                srank = 0;
098                for (int i = 0; i < irank; i++) { // see if shapes are consistent and subspace is intact
099                        Object obj = indexes.get(i);
100                        if (obj instanceof IntegerDataset && !restrict1D) {
101                                IntegerDataset ind = (IntegerDataset) obj;
102                                if (first > 0) {
103                                        intact = false;
104                                }
105
106                                int l = ind.size;
107                                if (ilength < l) {
108                                        ilength = l;
109                                        cshape = null;
110                                } else if (l != 1 && l != ilength) {
111                                        throw new IllegalArgumentException("Index datasets do not have same size");
112                                }
113                                if (cshape == null) {
114                                        cshape = ind.shape;
115                                        srank = cshape.length;
116                                        offset = i;
117                                } else if (l > 1 && !Arrays.equals(ind.shape, cshape)) { // broadcast
118                                        throw new IllegalArgumentException("Index datasets do not have same shape");
119                                }
120                        } else {
121                                if (cshape != null) {
122                                        if (first < 0)
123                                                first = i;
124                                }
125                        }
126                }
127
128                List<Integer> oShape = new ArrayList<Integer>(irank);
129
130                if (intact) { // get new output shape list
131                        boolean used = false;
132                        for (int i = 0; i < irank; i++) {
133                                Object obj = indexes.get(i);
134                                if (obj instanceof IntegerDataset) {
135                                        if (restrict1D || !used) {
136                                                used = true;
137                                                int[] lshape = restrict1D ? ((IntegerDataset) obj).shape : cshape;
138                                                for (int j : lshape) {
139                                                        oShape.add(j);
140                                                }
141                                        }
142                                } else if (obj instanceof Slice) {
143                                        Slice s = (Slice) obj;
144                                        int l = ishape[i];
145                                        s.setLength(l);
146                                        oShape.add(s.getNumSteps());
147                                } else {
148                                        oShape.add(ishape[i]);
149                                }
150                        }
151                } else {
152                        assert cshape != null;
153                        for (int j : cshape) {
154                                oShape.add(j);
155                        }
156                        for (int i = 0; i < irank; i++) {
157                                Object obj = indexes.get(i);
158                                if (obj == null) {
159                                        oShape.add(ishape[i]);
160                                } else if (obj instanceof Slice) {
161                                        Slice s = (Slice) obj;
162                                        int l = ishape[i];
163                                        s.setLength(l);
164                                        oShape.add(s.getNumSteps());
165                                }
166                        }
167                }
168                orank = oShape.size();
169                oshape = new int[orank];
170                for (int i = 0; i < orank; i++) {
171                        oshape[i] = oShape.get(i);
172                }
173
174                for (int i = 0; i < irank; i++) { // check input indexes for out of bounds
175                        Object obj = indexes.get(i);
176                        if (obj instanceof IntegerDataset) {
177                                IntegerDataset ind = (IntegerDataset) obj;
178                                if (ind.getSize() > 0) {
179                                        int l = ishape[i];
180                                        if (ind.min().intValue() < -l || ind.max().intValue() >= l) {
181                                                throw new IllegalArgumentException("A value in index datasets is outside permitted range");
182                                        }
183                                }
184                        }
185                }
186
187                ipos = new int[irank];
188                it = new PositionIterator(oshape);
189                opos = it.getPos();
190        }
191
192        @Override
193        public int[] getShape() {
194                return oshape;
195        }
196
197        @Override
198        public boolean hasNext() {
199                if (it.hasNext()) {
200                        int i = 0;
201                        for (; i < offset; i++) {
202                                Object obj = indexes.get(i);
203                                if (obj == null) {
204                                        ipos[i] = opos[i];
205                                } else if (obj instanceof Slice) {
206                                        Slice s = (Slice) obj;
207                                        ipos[i] = s.getPosition(opos[i]); // overwrite position
208                                } else {
209                                        throw new IllegalStateException("Bad state: index dataset before offset");
210                                }
211                        }
212                        int[] spos = srank > 0 ? Arrays.copyOfRange(opos, i, i+srank) : opos;
213                        if (spos == opos) {
214                                for (; i < irank; i++) {
215                                        Object obj = indexes.get(i);
216                                        if (obj == null) {
217                                                ipos[i] = opos[i];
218                                        } else if (obj instanceof Slice) {
219                                                Slice s = (Slice) obj;
220                                                ipos[i] = s.getPosition(opos[i]); // overwrite position
221                                        } else if (obj instanceof IntegerDataset) { // allowed when restricted to 1D
222                                                int p = ((Dataset) obj).getInt(opos[i]);
223                                                ipos[i] = p < 0 ? p + ishape[i] : p;
224                                        } else {
225                                                throw new IllegalStateException("Bad state: index dataset after subspace");
226                                        }
227                                }
228                        } else {
229                                for (int j = 0; j < irank; j++) {
230                                        Object obj = indexes.get(j);
231                                        if (obj instanceof IntegerDataset) {
232                                                IntegerDataset ind = (IntegerDataset) obj;
233                                                int p = ind.size > 1 ? ind.get(spos) : ind.getAbs(0); // broadcasting
234                                                ipos[i] = p < 0 ? p + ishape[i] : p;
235                                                i++;
236                                        }
237                                }
238                                int o = orank - irank;
239                                for (; i < irank; i++) {
240                                        Object obj = indexes.get(i);
241                                        if (obj == null) {
242                                                ipos[i] = opos[i+o];
243                                        } else if (obj instanceof Slice) {
244                                                Slice s = (Slice) obj;
245                                                ipos[i] = s.getPosition(opos[i+o]); // overwrite position
246                                        } else {
247                                                throw new IllegalStateException("Bad state: index dataset after subspace");
248                                        }
249                                }
250                        }
251//                      System.err.println(Arrays.toString(opos) + ", " + Arrays.toString(spos) + ", " + Arrays.toString(ipos));
252                        return true;
253                }
254                return false;
255        }
256
257        @Override
258        public int[] getPos() {
259                return ipos;
260        }
261
262        @Override
263        public void reset() {
264                it.reset();
265                Arrays.fill(ipos, 0);
266                index = 0;
267        }
268}