/*
* Redberry: symbolic tensor computations.
*
* Copyright (c) 2010-2013:
* 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.core.transformations;
import cc.redberry.core.tensor.Sum;
import cc.redberry.core.tensor.SumBuilderSplitingScalars;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.tensor.iterator.FromChildToParentIterator;
/**
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
* @since 1.1
*/
public final class CollectNonScalarsTransformation implements Transformation {
public static final CollectNonScalarsTransformation COLLECT_NON_SCALARS
= new CollectNonScalarsTransformation();
private CollectNonScalarsTransformation() {
}
@Override
public Tensor transform(Tensor t) {
return collectNonScalars(t);
}
public static Tensor collectNonScalars(Tensor t) {
FromChildToParentIterator iterator = new FromChildToParentIterator(t);
Tensor c;
while ((c = iterator.next()) != null)
if (c instanceof Sum) {
//TODO add check whether we need to do this transformation
SumBuilderSplitingScalars sbss = new SumBuilderSplitingScalars(c.size());
for (Tensor tt : c)
sbss.put(tt);
iterator.set(sbss.build());
}
return iterator.result();
}
}