private void unfoldAndOptimizeAndStore(IList <RewriteTreeElement> rewriteTreeElementsFromRootToChildrens)
{
RewriteTreeElement lastChildrenRewriteTreeElement = rewriteTreeElementsFromRootToChildrens[rewriteTreeElementsFromRootToChildrens.Count - 1];
// we have to copy because CausalSetNodeFuser.fuse() modifies the argument
CausalSetSystemBlock modifiedRootSystemBlock = unmodifiedRootSystemBlock.copyShallow();
CausalSetSystemBlock currentTopBlock = unmodifiedRootSystemBlock;
for (int rewriteChainIndex = 0; rewriteChainIndex < rewriteTreeElementsFromRootToChildrens.Count(); rewriteChainIndex++)
{
RewriteTreeElement iterationRewriteTreeElement = rewriteTreeElementsFromRootToChildrens[rewriteChainIndex];
CausalSetSystemBlock modifiedParent;
CausalSetSystemBlock afterFusion = CausalSetNodeFuser.fuse(currentTopBlock, out modifiedParent, iterationRewriteTreeElement.indicesOfParentNodesForRewrite.ToList());
currentTopBlock = afterFusion;
}
// linearize and calculate energy, store back to tree (in the children)
IList <uint> globalLinearized = linearizer.linearize(modifiedRootSystemBlock, /*recursive*/ true);
lastChildrenRewriteTreeElement.globalLinearized = GlobalLinearization.make(linearizer.linearize(modifiedRootSystemBlock, /*recursive*/ true));
Debug.Assert(lastChildrenRewriteTreeElement.globalLinearized.linearization.Count == unmodifiedRootSystemBlock.nodes.Count);
// calculate global energy
lastChildrenRewriteTreeElement.globalEnergyAfterRewrite = calculateEnergy(lastChildrenRewriteTreeElement.globalLinearized, modifiedRootSystemBlock);
}
// \param recursive do we recurse down if the embeded block is present
public IList <uint> linearize(CausalSetSystemBlock causalSystemBlock, bool recusive = false)
{
IList <uint> linearization = new List <uint>(); // (global) indices of nodes of the linearlization
linearizeInternal(causalSystemBlock, linearization, recusive);
return(linearization);
}
void buildTree(CausalSetSystemBlock entryBlock)
{
// store it for later reference for calculating the global energy
unmodifiedRootSystemBlock = entryBlock;
rootRewriteTreeElement = new RewriteTreeElement();
buildRewriteTreeRecursive(rootRewriteTreeElement, entryBlock.copyDeep());
}
public CausalSetSystemBlock copyDeep()
{
CausalSetSystemBlock copyResult = new CausalSetSystemBlock();
copyResult.indirectionArray = ArrayHelpers.copy(indirectionArray);
copyResult.indirectionCounter = indirectionCounter;
copyResult.entryIndices = entryIndices != null?ListHelpers.copy(entryIndices) : null;
foreach (CausalSetNode iteratorNode in nodes)
{
copyResult.nodes.Add(iteratorNode.copyDeep());
}
return(copyResult);
}
void buildRewriteTreeRecursive(RewriteTreeElement parentRewriteTreeElement, CausalSetSystemBlock recursedSystemBlock)
{
uint rewriteRounds = 1; // for now we just do one rewrite for testing
for (uint rewriteRound = 0; rewriteRound < rewriteRounds; rewriteRound++)
{
uint fuseEntryIndex = (uint)random.Next(recursedSystemBlock.nodes.Count);
RewriteTreeElement rewriteTreeElementAfterRewrite = new RewriteTreeElement();
rewriteTreeElementAfterRewrite.indicesOfParentNodesForRewrite = recursedSystemBlock.getRandomFollowerAsEnumerable(fuseEntryIndex, terminationPropability);
// rewrite
rewriteTreeElementAfterRewrite.blockAfterRewrite = CausalSetNodeFuser.fuse(recursedSystemBlock, out recursedSystemBlock, rewriteTreeElementAfterRewrite.indicesOfParentNodesForRewrite.ToList());
parentRewriteTreeElement.childrenRewrites.Add(rewriteTreeElementAfterRewrite);
}
}
void linearizeInternal(CausalSetSystemBlock causalSystemBlock, IList <uint> linearization, bool recusive)
{
causalSystemBlock.updateEntryIndices(); // we calculate this always new because we don't care about performance for now
IList <uint> indicesOfEntryNodes = causalSystemBlockAccessor.getEntryIndicesAsList(causalSystemBlock);
IList <uint> openNodeIndices = ListHelpers.copy(indicesOfEntryNodes);
ISet <uint> nodeIndicesInLinearization = new HashSet <uint>(); // set, bool values hae no meaning
while (!openNodeIndices.isEmpty())
{
uint currentCandidateNodeIndex;
{// choose random element from openNodeIndices and remove
uint candidateIndexOfOpenNodeIndices = (uint)random.Next(openNodeIndices.Count);
currentCandidateNodeIndex = openNodeIndices[(int)candidateIndexOfOpenNodeIndices];
openNodeIndices.RemoveAt((int)candidateIndexOfOpenNodeIndices);
}
Ensure.ensureHard(!nodeIndicesInLinearization.Contains(currentCandidateNodeIndex));
nodeIndicesInLinearization.Add(currentCandidateNodeIndex);
// if we can and should recurse down
if (recusive && causalSystemBlock.nodes[(int)currentCandidateNodeIndex].content != null)
{
CausalSetSystemBlock childrenBlock = causalSystemBlock.nodes[(int)currentCandidateNodeIndex].content;
linearizeInternal(childrenBlock, linearization, recusive);
}
else
{
// the global index must be valid
linearization.Add(causalSystemBlock.nodes[(int)currentCandidateNodeIndex].globalIndex.Value);
}
ISet <uint> nextIndicesOfCurrentCandidate = SetHelpers.subtract(causalSystemBlockAccessor.getNextIndicesOfNodeAsSet(causalSystemBlock, currentCandidateNodeIndex), nodeIndicesInLinearization);
openNodeIndices = SetHelpers.union(SetHelpers.toSet(openNodeIndices), nextIndicesOfCurrentCandidate).ToList();
}
}
private long calculateEnergy(GlobalLinearization linearization, CausalSetSystemBlock root)
{
IDictionary <uint, uint> indexInLinearizationByIndex = new Dictionary <uint, uint>();
for (uint i = 0; i < linearization.linearization.Count; i++)
{
uint nodeIndex = linearization.linearization[(int)i];
Ensure.ensureHard(!indexInLinearizationByIndex.ContainsKey(nodeIndex));
indexInLinearizationByIndex[nodeIndex] = i;
}
long energy = 0;
for (uint indexInLinearization = 0; indexInLinearization < linearization.linearization.Count; indexInLinearization++)
{
uint nodeIndex = linearization.linearization[(int)indexInLinearization];
foreach (CausalIndirectionIndex nextNodeIndicesFromCurrentNode in unmodifiedRootSystemBlock.nodes[(int)nodeIndex].next)
{
uint nextNodeIndexFromCurrentNode = root.translateIndirectIndexToIndex(nextNodeIndicesFromCurrentNode);
// translate the index of the next node which follows the current node to the index in the linearization
uint indexInLinearizationOfNextNode = indexInLinearizationByIndex[nextNodeIndexFromCurrentNode];
// calculate energy from current node to next node based on linearization
Debug.Assert(indexInLinearizationOfNextNode >= 0);
int energyFromCurrentNodeToNextNode = (int)indexInLinearizationOfNextNode - (int)indexInLinearization;
// must be greater than zero else we have some really nasty bug in the code
Ensure.ensureHard(energyFromCurrentNodeToNextNode > 0);
energy += energyFromCurrentNodeToNextNode;
}
}
return(energy);
}
public void entry(CausalSetSystemBlock entryBlock)
{
Ensure.ensureHard(rootRewriteTreeElement == null);
buildTree(entryBlock);
}
public CausalSetNode(CausalSetSystemBlock content = null)
{
this.content = content;
}
// creates a new block with the content as the fused nodes and fuses the nodes in the "entryBlock" and returns the created "CausalSystemBlock" which contains all fused nodes on the next level
// entryblock doesn't get modified
static public CausalSetSystemBlock fuse(CausalSetSystemBlock entryBlock, out CausalSetSystemBlock modifiedEntryBlock, IList <uint> indices)
{
CausalSetSystemBlock modifiedEntryBlock_localVar = entryBlock.copyDeep();
CausalSetSystemBlock higherLevelBlock = new CausalSetSystemBlock();
// fill higherLevelBlock with as many nodes as required
foreach (uint iterationIndex in indices)
{
CausalSetNode createdNode = new CausalSetNode();
createdNode.nodeIndexInParentSystemBlock = iterationIndex;
higherLevelBlock.nodes.Add(createdNode);
higherLevelBlock.indirectionArray.Add(higherLevelBlock.getNewIndirectionNumber());
}
// translates the index in entryBlock to the index in higherLevelBlock
Dictionary <uint, uint> indexToElementInHigherLevelBlock = new Dictionary <uint, uint>();
for (uint i = 0; i < indices.Count; i++)
{
uint redirectedIndex = indices[(int)i];
indexToElementInHigherLevelBlock[redirectedIndex] = i;
}
// rewire from entryBlock the subnetwork to HigherLevelBlock
foreach (Tuple <uint, CausalSetNode> iterationIndexAndNodePair in indices.Select(index => new Tuple <uint, CausalSetNode>(index, modifiedEntryBlock_localVar.getNodeByIndex(index))))
{
uint higherLevelBlock_index = indexToElementInHigherLevelBlock[iterationIndexAndNodePair.Item1];
var nextValidIndicesFromIterationNode =
iterationIndexAndNodePair.Item2.next
.Select(nextIndirection => modifiedEntryBlock_localVar.translateIndirectIndexToIndex(nextIndirection))
.Where(index => indexToElementInHigherLevelBlock.ContainsKey(index)); // if the node points to an node which is not in nextLevelBlock then we ignore it
foreach (uint iterationNextValidIndexFromIterationNode in nextValidIndicesFromIterationNode)
{
uint higherLevelBlock_nextIndex = indexToElementInHigherLevelBlock[iterationNextValidIndexFromIterationNode];
// make sure that the indirection is an identity
// only this way we don't have to do an inverse lookup to get the CausalIndirectionIndex
Ensure.ensureHard(higherLevelBlock.translateIndirectIndexToIndex(new CausalIndirectionIndex(higherLevelBlock_nextIndex)) == higherLevelBlock_nextIndex);
higherLevelBlock.nodes[(int)higherLevelBlock_index].next.Add(new CausalIndirectionIndex(higherLevelBlock_nextIndex));
}
}
// transfer global index
// global indices of fused nodes get reset to null by fuse so we ignore them
for (uint i = 0; i < indices.Count; i++)
{
uint entryBlockIndex = indices[(int)i];
uint higherLevelBlock_index = indexToElementInHigherLevelBlock[entryBlockIndex];
higherLevelBlock.nodes[(int)higherLevelBlock_index].globalIndex = modifiedEntryBlock_localVar.nodes[(int)entryBlockIndex].globalIndex;
}
// now do the fuse
uint fuseAsIndirectionNumber = modifiedEntryBlock_localVar.getNewIndirectionNumber();
modifiedEntryBlock_localVar.fuse(indices, fuseAsIndirectionNumber);
// add fused node
modifiedEntryBlock_localVar.nodes.Add(new CausalSetNode(higherLevelBlock));
// remove fused nodes and rewire indirectionArray accordingly
indices.ToList().Sort();
var reversedSortedIndices = indices.Reverse();
foreach (uint iterationNodeIndex in reversedSortedIndices)
{
// redirect all indices pointing at the element behind the removed one to one before it
modifiedEntryBlock_localVar.indirectionArray = modifiedEntryBlock_localVar.indirectionArray.Select(v => v > iterationNodeIndex ? v - 1 : v).ToList();
modifiedEntryBlock_localVar.nodes.RemoveAt((int)iterationNodeIndex);
}
modifiedEntryBlock = modifiedEntryBlock_localVar;
return(higherLevelBlock);
}
public ISet <uint> getNextIndicesOfNodeAsSet(CausalSetSystemBlock causalSystemBlock, uint nodeIdx)
{
uint[] nodeIndicesAsList = causalSystemBlock.nodes[(int)nodeIdx].next.Select(n => causalSystemBlock.indirectionArray[(int)n.value]).ToArray();
return(SetHelpers.toSet(nodeIndicesAsList));
}
public IList <uint> getEntryIndicesAsList(CausalSetSystemBlock causalSystemBlock)
{
return(causalSystemBlock.entryIndices);
}
