Commit 1bc4a281 authored by Alvarez, Gonzalo's avatar Alvarez, Gonzalo
Browse files

MPS Simplify

parent e47e0feb

src/Engine/Builder1D.h

+3 −2
Original line number Diff line number Diff line
@@ -194,11 +194,12 @@ private: 
	{

		assert(sites_ > 2);

		const SizeType nMinusOne = sites_ - 1;

		const PsimagLite::String name = "a";



		srep_ = "u0(s" + ttos(nMinusOne) + ",f0|s0)";

		srep_ = name + "0(s" + ttos(nMinusOne) + ",f0|s0)";



		for (SizeType i = 0; i < nMinusOne; ++i) {

			srep_ +=  "u" + ttos(i+1) + "(s" + ttos(i) + ",f" + ttos(i+1) + "|s" + ttos(i+1) + ")";

			srep_ +=  name + ttos(i+1) + "(s" + ttos(i) + ",f" + ttos(i+1) + "|s" + ttos(i+1) + ")";

		}

	}

src/Engine/TensorSrep.h

+50 −6
Original line number Diff line number Diff line
@@ -458,12 +458,13 @@ private: 
	{

		bool simplificationHappended = false;

		SizeType ntensors = data_.size();

		const bool mpsMode = (data_[0]->fullName()[0] == 'a');

		for (SizeType i = 0; i < ntensors; ++i) {

			if (data_[i]->isConjugate()) continue;

			SizeType j = findConjugate(i);

			if (j >= data_.size()) continue; // no conjugate

			if (!inputsMatch(i,j)) continue;

			if (!simplify(i,j)) continue;

			if (!inputsMatchShim(mpsMode, i, j)) continue;

			if (!simplify(mpsMode, i, j)) continue;

			simplificationHappended = true;

			break; // only one simplification

		}
@@ -471,12 +472,12 @@ private: 
		return simplificationHappended;

	}



	bool simplify(SizeType ind, SizeType jnd)

	bool simplify(bool mpsMode, SizeType ind, SizeType jnd)

	{

		bool simplificationHappended = false;

		SizeType outs = data_[ind]->outs();

		VectorPairSizeType replacements(outs);

		if (!computeReplacements(replacements,ind,jnd))

		VectorPairSizeType replacements((mpsMode) ? 2 : outs);

		if (!computeReplacementsShim(mpsMode, replacements, ind, jnd))

			return simplificationHappended;



		data_[ind]->setAsErased();
@@ -517,6 +518,15 @@ private: 
		}

	}



	bool computeReplacementsShim(bool mpsMode,

	                             VectorPairSizeType& replacements,

	                             SizeType ind,

	                             SizeType jnd) const

	{

		return (mpsMode) ? computeReplacementsMPS(replacements, ind, jnd )

		                 : computeReplacements(replacements, ind, jnd);

	}



	bool computeReplacements(VectorPairSizeType& replacements,

	                         SizeType ind,

	                         SizeType jnd) const
@@ -538,6 +548,30 @@ private: 
		return true;

	}



	bool computeReplacementsMPS(VectorPairSizeType& replacements,

	                            SizeType ind,

	                            SizeType jnd) const

	{

		for (SizeType leg = 0; leg < 3; ++leg) {

			if (leg == 1) continue;

			if (data_[ind]->legType(leg) != TensorStanzaType::INDEX_TYPE_SUMMED)

				return false;

			if (data_[jnd]->legType(leg) != TensorStanzaType::INDEX_TYPE_SUMMED)

				return false;

			const SizeType s1 = data_[ind]->legTag(leg);

			const SizeType s2 = data_[jnd]->legTag(leg);

			SizeType x = (leg == 0) ? 0 : 1;

			replacements[x] = PairSizeType((s1 < s2) ? s2 : s1,(s1 < s2) ? s1 : s2);

		}



		return true;

	}



	bool inputsMatchShim(bool mpsMode, SizeType ind, SizeType jnd) const

	{

		return (mpsMode) ? inputsMatchMPS(ind, jnd) : inputsMatch(ind, jnd);

	}



	bool inputsMatch(SizeType ind, SizeType jnd) const

	{

		SizeType ins = data_[ind]->ins();
@@ -554,6 +588,16 @@ private: 
		return true;

	}



	bool inputsMatchMPS(SizeType ind, SizeType jnd) const

	{

		SizeType ins = data_[ind]->ins();

		if (ins != data_[jnd]->ins()) return false;

		if (ins < 2) return false;

		return (data_[ind]->legTag(1) == data_[jnd]->legTag(1) &&

		        data_[ind]->legType(1) == TensorStanzaType::INDEX_TYPE_SUMMED &&

		        data_[jnd]->legType(1) == TensorStanzaType::INDEX_TYPE_SUMMED);

	}



	void append(const TensorSrep& other)

	{

		SizeType ntensors = data_.size();