/*
* 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;
import java.util.Arrays;
import java.util.List;
import cc.redberry.core.tensor.AbstractTensorWrapper;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.tensor.TensorNumber;
import cc.redberry.core.tensor.TensorWrapper;
import cc.redberry.core.tensor.iterators.TensorTreeIterator;
import cc.redberry.core.tensor.iterators.TensorTreeIteratorFactory;
/**
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
*/
public class Transformer implements Transformation {
private List<Transformation> transformations;
public Transformer(Transformation... transformations) {
this.transformations = Arrays.asList(transformations);
}
public Transformer(List<Transformation> transformations) {
this.transformations = transformations;
}
@Override
public Tensor transform(Tensor tensor) {
return transform(tensor, false);
}
public Tensor transform(Tensor tensor, boolean tensorFirst) {
//TODO review
//Remembing parent
Tensor parent = tensor.getParent();
TensorWrapper wrapper = new TensorWrapper(tensor);
TensorTreeIterator it = TensorTreeIteratorFactory.create(tensorFirst, wrapper);
Tensor current, old;
while (it.hasNext()) {
old = current = it.next();
for (Transformation transformation : transformations)
if ((current = transformation.transform(current)) == null)
break;
if (current == null)
if (AbstractTensorWrapper.onInnerTensorIndicator.is(it))
it.set(TensorNumber.createZERO());
else
it.remove();
else if (old != current)
it.set(current);
}
Tensor result = wrapper.getInnerTensor();
result.setParent(parent);
return result;
}
}