/*
* 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.ArrayList;
import java.util.List;
import cc.redberry.concurrent.InputPortUnsafe;
import cc.redberry.core.tensor.Product;
import cc.redberry.core.tensor.Sum;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.tensor.TensorNumber;
import cc.redberry.core.tensor.Pow;
import cc.redberry.core.tensor.testing.TTest;
import cc.redberry.transformation.Transformations;
/**
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
*/
public class CollectPowersInputPort implements InputPortUnsafe<Tensor> {
private final List<Pair> collected = new ArrayList<>();
private boolean closed = false;
@Override
public void put(Tensor tensor) {
if (closed)
throw new RuntimeException("Port is closed.");
if (tensor == null) {
closed = true;
return;
}
Tensor inner;
Tensor power;
if (tensor instanceof Pow) {
inner = ((Pow) tensor).getTarget();
power = ((Pow) tensor).getPower();
} else {
inner = tensor;
power = TensorNumber.createONE();
}
for (Pair pair : collected)
if (TTest.testParity(pair.innerTensor, inner)) {
pair.add(power);
return;
}
collected.add(new Pair(inner, power));
}
public boolean isEmpty() {
return collected.isEmpty();
}
public Tensor getResult() {
Product result = new Product();
for (Pair p : collected)
result.add(p.get());
return result.equivalent();
}
private static class Pair {
Tensor innerTensor;
Sum power = new Sum();
Pair(Tensor innerTensor, Tensor power) {
this.innerTensor = innerTensor;
this.power.add(power);
}
void add(Tensor power) {
this.power.add(power);
}
Tensor get() {
Tensor pow = Transformations.calculateNumbers(power);
pow = CollectEquals.INSTANCE.transform(pow).equivalent();
if (pow instanceof TensorNumber && ((TensorNumber) pow).isOne())
return innerTensor;
return new Pow(innerTensor, pow);
}
}
}