File DensityNode.hpp¶

Density-matrix DD node, edge and cached-edge types.

This is a self-contained copy of the density-matrix support that used to live in the MQT Core DD package (dd::dNode, dd::dEdge, dd::dCachedEdge) before it was removed in https://github.com/munich-quantum-toolkit/core/pull/1466. It lives in the separate namespace dd::ddsim so that it can coexist with a Core version that still provides the old types.

namespace dd

namespace ddsim

Typedefs

using DensityMatrixDD = dEdge ¶

Functions

inline dEdge densityFromMatrixEdge(const dd::mEdge &e)¶: Reinterpret a Core matrix edge as a density-matrix edge.

struct dCachedEdge¶

#include <DensityNode.hpp>

A density-matrix DD node with a cached (non-canonical) edge weight.

Public Functions

dCachedEdge() = default¶

inline dCachedEdge(dNode *n, const dd::ComplexValue &v)¶

inline dCachedEdge(dNode *n, const dd::Complex &c)¶

inline bool operator==(const dCachedEdge &other) const¶

inline bool operator!=(const dCachedEdge &other) const¶

inline bool isTerminal() const¶

inline bool isIdentity(bool upToGlobalPhase = true) const¶

Public Members

dNode *p = {}¶

dd::ComplexValue w¶

Public Static Functions

static inline dCachedEdge terminal(const dd::ComplexValue &w)¶

static inline dCachedEdge terminal(const std::complex<dd::fp> &w)¶

static inline dCachedEdge terminal(const dd::Complex &w)¶

static inline dCachedEdge zero()¶

static inline dCachedEdge one()¶

static auto normalize(dNode *p, const std::array<dCachedEdge, dd::NEDGE> &e, dd::MemoryManager &mm, dd::ComplexNumbers &cn) -> dCachedEdge ¶: Get a normalized density-matrix DD from a fresh node and its edges.

struct dEdge¶

#include <DensityNode.hpp>

A weighted edge pointing to a density-matrix DD node.

Public Functions

inline constexpr bool operator==(const dEdge &other) const¶

inline constexpr bool operator!=(const dEdge &other) const¶

inline bool isTerminal() const¶

inline bool isZeroTerminal() const¶

inline bool isOneTerminal() const¶

inline bool isIdentity(bool upToGlobalPhase = true) const¶

std::size_t size() const¶: Get the size of the DD (number of nodes including the terminal).

void mark() const noexcept¶: Mark the edge (and its sub-DD) as used.

void unmark() const noexcept¶: Unmark the edge (and its sub-DD).

dd::SparsePVecStrKeys getSparseProbabilityVectorStrKeys(std::size_t numQubits, dd::fp threshold = 0.) const¶: Get the sparse probability vector using strings as keys.

Public Members

dNode *p¶

dd::Complex w¶

Public Static Functions

static inline constexpr dEdge zero()¶

static inline constexpr dEdge one()¶

static constexpr dEdge terminal(const dd::Complex &w)¶: Inline definitions that require the complete dNode type

static inline bool trackingRequired(const dEdge &e)¶

static auto normalize(dNode *p, const std::array<dEdge, dd::NEDGE> &e, dd::MemoryManager &mm, dd::ComplexNumbers &cn) -> dEdge ¶: Get a normalized density-matrix DD from a fresh node and its edges.

static inline void setDensityMatrixTrue(dEdge &e)¶

static inline void alignDensityEdge(dEdge &e)¶

static inline void revertDmChangesToEdges(dEdge &x, dEdge &y)¶

static inline void revertDmChangesToEdge(dEdge &x)¶

static inline void applyDmChangesToEdges(dEdge &x, dEdge &y)¶

static inline void applyDmChangesToEdge(dEdge &x)¶

Private Functions

std::size_t size(std::unordered_set<const dNode*> &visited) const¶

void traverseDiagonal(const dd::fp &prob, std::size_t i, const dd::ProbabilityFunc &f, std::size_t level, dd::fp threshold = 0.) const¶

struct dNode : public dd::NodeBase¶

#include <DensityNode.hpp>

A density-matrix DD node.

Data Layout (8)|(2|2|4)|(24|24|24|24) = 112B

Public Functions

inline dNode *next() const noexcept¶: Getter for the next object.

inline bool isMarked() const noexcept¶: Check whether the node is marked as used.

inline void mark() noexcept¶: Mark the node as used.

inline void unmark() noexcept¶: Unmark the node.

inline constexpr void unsetTempDensityMatrixFlags() noexcept¶

void setDensityMatrixNodeFlag(bool densityMatrix) noexcept¶

Public Members

std::array<dEdge, dd::NEDGE> e = {}¶

Public Static Functions

static inline constexpr dNode *getTerminal() noexcept¶: Getter for the terminal object.

static inline bool isTerminal(const dNode *p) noexcept¶

Check whether a pointer represents a terminal density node.

Density nodes encode temporary state in the three least significant pointer bits. These bits do not make a terminal pointer non-terminal.

static inline constexpr bool tempDensityMatrixFlagsEqual(const std::uint8_t a, const std::uint8_t b) noexcept¶

static inline constexpr bool isConjugateTempFlagSet(const std::uintptr_t p) noexcept¶

static inline constexpr bool isNonReduceTempFlagSet(const std::uintptr_t p) noexcept¶

static inline constexpr bool isDensityMatrixTempFlagSet(const std::uintptr_t p) noexcept¶

static inline bool isDensityMatrixNode(const std::uintptr_t p) noexcept¶

static inline bool isConjugateTempFlagSet(const dNode *p) noexcept¶

static inline bool isNonReduceTempFlagSet(const dNode *p) noexcept¶

static inline bool isDensityMatrixTempFlagSet(const dNode *p) noexcept¶

static inline bool isDensityMatrixNode(const dNode *p) noexcept¶

static inline void setConjugateTempFlagTrue(dNode *&p) noexcept¶

static inline void setNonReduceTempFlagTrue(dNode *&p) noexcept¶

static inline void setDensityMatTempFlagTrue(dNode *&p) noexcept¶

static inline void alignDensityNode(dNode *&p) noexcept¶

static inline std::uintptr_t getDensityMatrixTempFlags(dNode *&p) noexcept¶

static inline constexpr std::uintptr_t getDensityMatrixTempFlags(const std::uintptr_t a) noexcept¶

static std::uint8_t alignDensityNodeNode(dNode *&p) noexcept¶

static void getAlignedNodeRevertModificationsOnSubEdges(dNode *p) noexcept¶

static void applyDmChangesToNode(dNode *&p) noexcept¶

static void revertDmChangesToNode(dNode *&p) noexcept¶

Public Static Attributes

static constexpr std::uint16_t MARK_FLAG = 0b10000U¶: Mark flag used for mark-and-sweep garbage collection.