}
@Override
public Tensor transform(Tensor tensor) {
SubstitutionIterator iterator = new SubstitutionIterator(tensor);
Tensor current;
OUT:
while ((current = iterator.next()) != null) {
if (!(current instanceof TensorField))
continue;
TensorField currentField = (TensorField) current;
IndexMappingBuffer buffer = IndexMappings.simpleTensorsPort(from, currentField).take();
if (buffer == null)
continue;
Indices[] fromIndices = from.getArgIndices(), currentIndices = currentField.getArgIndices();
List<Transformation> transformations = new ArrayList<>();
Tensor fArg;
int[] cIndices, fIndices;
int i;
for (i = from.size() - 1; i >= 0; --i) {
if (IndexMappings.mappingExists(current.get(i), from.get(i)))
continue;
fIndices = fromIndices[i].getAllIndices().copy();
cIndices = currentIndices[i].getAllIndices().copy();
assert cIndices.length == fIndices.length;
fArg = ApplyIndexMapping.applyIndexMapping(from.get(i), fIndices, cIndices, new int[0]);
transformations.add(Substitutions.getTransformation(fArg, current.get(i)));
}
Tensor newTo;
if (symbolic)
newTo = to;
else {
int[] forbidden = new int[iterator.forbiddenIndices().size()];
int c = -1;
for (Integer f : iterator.forbiddenIndices())
forbidden[++c] = f;
newTo = ApplyIndexMapping.applyIndexMapping(to, buffer, forbidden);
// if (newTo != to)
iterator.forbiddenIndices().addAll(TensorUtils.getAllIndicesNames(newTo));
}
for (Transformation transformation : transformations)
newTo = transformation.transform(newTo);
if (!symbolic) {
int[] forbidden = new int[iterator.forbiddenIndices().size()];
int c = -1;
for (Integer f : iterator.forbiddenIndices())
forbidden[++c] = f;
Tensor temp = newTo;
newTo = ApplyIndexMapping.renameDummy(temp, forbidden);
if (temp != newTo)
iterator.forbiddenIndices().addAll(TensorUtils.getAllIndicesNames(newTo));
}