/*
* Redberry: symbolic tensor computations.
*
* Copyright (c) 2010-2012:
* Stanislav Poslavsky <stvlpos@mail.ru>
* Bolotin Dmitriy <bolotin.dmitriy@gmail.com>
*
* This file is part of Redberry.
*
* Redberry 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.
*
* Redberry 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 Redberry. If not, see <http://www.gnu.org/licenses/>.
*/
package cc.redberry.transformation.collect;
import java.util.ArrayDeque;
import java.util.Deque;
import cc.redberry.core.tensor.Sum;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.tensor.TensorIterator;
import cc.redberry.core.tensor.testing.TTest;
import cc.redberry.transformation.Transformation;
/**
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
*/
public class PatternCollectManager implements Transformation{
private final Deque<SplitPattern> patterns;
private Deque<SplitPattern> tempPatterns;
boolean reset = true;
public PatternCollectManager(Deque<SplitPattern> patterns) {
this.patterns = patterns;
}
private void reset() {
tempPatterns = new ArrayDeque<>();
for (SplitPattern sp : patterns)
tempPatterns.add(sp);
reset = false;
}
@Override
public Tensor transform(Tensor target) {
if (!(target instanceof Sum))
return target;
if (reset)
reset();
//main routine
Tensor result = collect1(target);
reset = true;
return result;
}
private Tensor collect1(Tensor target) {
//main routine
if (!(target instanceof Sum))
return target;
if (tempPatterns.isEmpty()) {
if (TTest.testIsScalar(target)) {
CollectTerms act = new CollectTerms(ScalarsSplitCriteria.INSTANCE);
return act.transform(target);
}
CollectTerms act = new CollectTerms(EqualsSplitCriteria.INSTANCE);
return act.transform(target);
}
SplitPattern currentPattern = tempPatterns.poll();
CollectTerms act = new CollectTerms(new PatternSplitCriteria(currentPattern));
target = act.transform(target);
if (!(target instanceof Sum))
return target;
for (Tensor term : target) {
TensorIterator it = term.iterator();
Tensor multiplyer;
while (it.hasNext()) {
multiplyer = it.next();
if (multiplyer instanceof Sum)
it.set(collect1(multiplyer)); // break;
}
}
return target;
}
}