/*
* 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.contractions;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import cc.redberry.core.context.CC;
import cc.redberry.core.indices.Indices;
import cc.redberry.core.indexgenerator.IndexGenerator;
import cc.redberry.core.tensor.Product;
import cc.redberry.core.tensor.SimpleTensor;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.indexmapping.IndexMappingDirectAllowingUnmapped;
import cc.redberry.core.transformations.ApplyIndexMappingDirectTransformation;
import cc.redberry.transformation.Transformation;
import cc.redberry.core.utils.TensorUtils;
import static cc.redberry.core.indices.IndicesUtils.*;
/**
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
*/
public class UncontractIndicesTransformation implements Transformation {
final List<Tensor> kroneckers = new ArrayList<>();
final List<Integer> checked = new ArrayList<>();
final List<Integer> uncontracted = new ArrayList<>();
final int[] usedIndicesNames;
public UncontractIndicesTransformation() {
usedIndicesNames = new int[0];
}
public UncontractIndicesTransformation(Indices toUncontracct) {
for (int i = 0; i < toUncontracct.size(); ++i)
checked.add(inverseIndexState(toUncontracct.get(i)));
usedIndicesNames = new int[0];
}
public UncontractIndicesTransformation(int[] usedIndicesNames) {
this.usedIndicesNames = usedIndicesNames;
Arrays.sort(this.usedIndicesNames);
}
public UncontractIndicesTransformation(Indices toUncontracct, int[] usedIndicesNames) {
for (int i = 0; i < toUncontracct.size(); ++i)
checked.add(inverseIndexState(toUncontracct.get(i)));
this.usedIndicesNames = usedIndicesNames;
Arrays.sort(this.usedIndicesNames);
}
public List<Tensor> getKroneckers() {
return kroneckers;
}
public List<Integer> getUncontracted() {
return uncontracted;
}
@Override
public Tensor transform(Tensor tensor) {
Product result = new Product();
result.add(renameIndicesAndBuidKroneckers(tensor));
result.add(kroneckers);
return result.equivalent();
}
public Tensor renameIndicesAndBuidKroneckers(Tensor tensor) {
if (tensor instanceof SimpleTensor || tensor instanceof Product) {
Indices indices = tensor.getIndices();
IndexMappingDirectAllowingUnmapped im = new IndexMappingDirectAllowingUnmapped();
IndexMappingDirectAllowingUnmapped renameUsedIndices = null;
IndexGenerator ig;
ig = new IndexGenerator(TensorUtils.getAllIndicesBuilder(tensor).append(usedIndicesNames).asArray());
for (int i = 0; i < indices.size(); ++i) {
int index = indices.get(i);
if (checked.contains(inverseIndexState(index)))
if (usedIndicesNames.length == 0 || Arrays.binarySearch(usedIndicesNames, getNameWithType(index)) < 0) {
// uncontracted.add(inverseIndexState(index));
int newIndex = getRawStateInt(index) | ig.generate(getType(index));
uncontracted.add(getNameWithType(index));
uncontracted.add(getNameWithType(newIndex));
im.add(index, newIndex);
} else {
if (renameUsedIndices == null)
renameUsedIndices = new IndexMappingDirectAllowingUnmapped();
int newIndex = getRawStateInt(index) | ig.generate(getType(index));
int kroneckerIndex = getRawStateInt(index) | ig.generate(getType(index));
renameUsedIndices.add(index, kroneckerIndex);
renameUsedIndices.add(inverseIndexState(index), inverseIndexState(newIndex));
im.add(newIndex, kroneckerIndex);
uncontracted.add(getNameWithType(newIndex));
uncontracted.add(getNameWithType(kroneckerIndex));
}
else
checked.add(index);
}
if (im.isEmpty())
return tensor;
//biulding kroneckers
for (Map.Entry<Integer, Integer> entry : im.getMap().entrySet())
kroneckers.add(CC.createKronecker(entry.getKey(), inverseIndexState(entry.getValue())));
if (renameUsedIndices != null)
im.add(renameUsedIndices);
// ApplyIndexMappingDirectTransformation.INSTANCE.perform(tensor, renameUsedIndices);
ApplyIndexMappingDirectTransformation.INSTANCE.perform(tensor, im);
}
return tensor;
}
}