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Advanced Tutorial

This tutorial covers advanced features and techniques for building sophisticated quantum entangled knowledge graphs. We'll explore complex reasoning patterns, optimization strategies, and advanced quantum operations.

Prerequisites

Before proceeding with this tutorial, ensure you have completed the Basic Usage Tutorial and are familiar with:

  • Basic quantum graph operations
  • Entanglement concepts
  • Query engine fundamentals
  • Visualization basics

Advanced Graph Construction

Multi-Domain Knowledge Integration

Learn to build complex graphs that span multiple knowledge domains:

from qekgr import EntangledGraph, QuantumNode, EntangledEdge
import numpy as np

# Create a large-scale multi-domain graph
multi_domain_graph = EntangledGraph(hilbert_dim=16)

# Define domain-specific node types and properties
domains = {
    "biology": {
        "protein": ["p53", "BRCA1", "insulin"],
        "gene": ["TP53", "BRCA1", "INS"],
        "disease": ["cancer", "diabetes"]
    },
    "chemistry": {
        "compound": ["aspirin", "caffeine", "glucose"],
        "element": ["carbon", "oxygen", "hydrogen"],
        "reaction": ["oxidation", "reduction"]
    },
    "medicine": {
        "drug": ["ibuprofen", "metformin", "warfarin"],
        "symptom": ["pain", "inflammation", "fever"],
        "treatment": ["chemotherapy", "surgery"]
    }
}

# Add nodes with domain-specific quantum properties
for domain, categories in domains.items():
    for category, entities in categories.items():
        for entity in entities:
            # Create domain-specific quantum states
            domain_amplitude = 0.8 if domain == "biology" else 0.6

            node = QuantumNode(
                entity,
                node_type=category,
                domain=domain,
                amplitude=domain_amplitude,
                properties={
                    "domain_specificity": domain_amplitude,
                    "category_weight": len(entities) / 10.0
                }
            )
            multi_domain_graph.add_node(node)

print(f"Multi-domain graph: {len(multi_domain_graph.nodes)} nodes")

Complex Entanglement Patterns

Implement sophisticated entanglement patterns for rich knowledge representation:

def create_cross_domain_entanglements(graph, strength_matrix):
    """Create complex entanglement patterns across domains."""

    # Define cross-domain relationship patterns
    cross_domain_patterns = [
        # Biology-Medicine connections
        ("p53", "cancer", "biomarker_for", 0.9),
        ("BRCA1", "chemotherapy", "treatment_target", 0.8),
        ("insulin", "diabetes", "regulates", 0.95),

        # Chemistry-Medicine connections  
        ("aspirin", "pain", "treats", 0.85),
        ("glucose", "diabetes", "related_to", 0.7),
        ("carbon", "chemotherapy", "component_of", 0.6),

        # Biology-Chemistry connections
        ("protein", "compound", "interacts_with", 0.7),
        ("gene", "element", "composed_of", 0.8),
        ("oxidation", "cancer", "contributes_to", 0.6)
    ]

    # Add quantum entangled edges
    for source, target, relation, base_strength in cross_domain_patterns:
        if source in graph.nodes and target in graph.nodes:
            # Apply quantum interference for strength modulation
            quantum_mod = np.random.normal(1.0, 0.1)  # Quantum uncertainty
            final_strength = min(0.99, max(0.1, base_strength * quantum_mod))

            edge = EntangledEdge(
                source, target,
                relation=relation,
                entanglement_strength=final_strength,
                quantum_phase=np.random.uniform(0, 2*np.pi)  # Quantum phase
            )
            graph.add_edge(edge)

# Apply complex entanglement patterns
create_cross_domain_entanglements(multi_domain_graph, None)
print(f"Added entanglements: {len(multi_domain_graph.edges)} edges")

Hierarchical Quantum Structures

Build hierarchical knowledge structures with quantum superposition:

def create_hierarchical_structure(graph, hierarchy_data):
    """Create hierarchical knowledge with quantum superposition."""

    # Example: Medical hierarchy
    medical_hierarchy = {
        "Disease": {
            "children": ["Cancer", "Metabolic Disease"],
            "quantum_weight": 1.0
        },
        "Cancer": {
            "children": ["Breast Cancer", "Lung Cancer"],
            "quantum_weight": 0.8,
            "parent": "Disease"
        },
        "Metabolic Disease": {
            "children": ["Diabetes", "Obesity"],
            "quantum_weight": 0.8,
            "parent": "Disease"
        },
        "Breast Cancer": {
            "children": ["BRCA1 Cancer", "Sporadic Cancer"],
            "quantum_weight": 0.6,
            "parent": "Cancer"
        }
    }

    # Create hierarchical nodes with quantum superposition
    for concept, data in medical_hierarchy.items():
        # Create superposed state representing concept hierarchy
        children = data.get("children", [])
        parent = data.get("parent", None)

        # Quantum amplitudes for hierarchical relationships
        if children:
            child_amplitudes = [data["quantum_weight"] / len(children)] * len(children)
        else:
            child_amplitudes = [data["quantum_weight"]]

        # Add hierarchical node
        hierarchical_node = QuantumNode(
            concept,
            node_type="concept",
            hierarchy_level=len(concept.split()) - 1,
            quantum_amplitudes=child_amplitudes
        )
        graph.add_node(hierarchical_node)

        # Create hierarchical entanglements
        if parent:
            parent_edge = EntangledEdge(
                parent, concept,
                relation="parent_of",
                entanglement_strength=0.9,
                edge_type="hierarchical"
            )
            graph.add_edge(parent_edge)

        for child in children:
            child_edge = EntangledEdge(
                concept, child,
                relation="child_of", 
                entanglement_strength=0.8,
                edge_type="hierarchical"
            )
            graph.add_edge(child_edge)

# Create hierarchical structure
create_hierarchical_structure(multi_domain_graph, None)

Advanced Quantum Operations

Quantum State Manipulation

Perform sophisticated quantum state operations:

from qekgr import QuantumInference
import scipy.linalg as la

def advanced_quantum_operations(graph):
    """Demonstrate advanced quantum state manipulation."""

    # 1. Quantum State Superposition
    def create_knowledge_superposition(node_ids, weights=None):
        """Create superposed state across multiple knowledge nodes."""
        if weights is None:
            weights = [1.0/len(node_ids)] * len(node_ids)

        # Normalize weights for quantum superposition
        norm = np.sqrt(sum(w**2 for w in weights))
        normalized_weights = [w/norm for w in weights]

        superposed_state = np.zeros(graph.hilbert_dim, dtype=complex)
        for i, (node_id, weight) in enumerate(zip(node_ids, normalized_weights)):
            if node_id in graph.nodes:
                node_state = graph.get_node_state(node_id)
                superposed_state += weight * node_state

        return superposed_state

    # Create superposition of related medical concepts
    medical_concepts = ["cancer", "chemotherapy", "p53"]
    medical_superposition = create_knowledge_superposition(
        medical_concepts, 
        weights=[0.6, 0.8, 0.4]
    )
    print(f"Medical superposition norm: {np.linalg.norm(medical_superposition):.3f}")

    # 2. Quantum Entanglement Manipulation
    def enhance_entanglement(node1, node2, enhancement_factor=1.2):
        """Enhance entanglement between two nodes using quantum operations."""
        if (node1, node2) in graph.edges:
            current_edge = graph.edges[(node1, node2)]
            new_strength = min(0.99, current_edge.entanglement_strength * enhancement_factor)

            # Apply quantum gate operation
            enhanced_edge = EntangledEdge(
                node1, node2,
                relation=current_edge.relation,
                entanglement_strength=new_strength,
                quantum_phase=current_edge.quantum_phase + np.pi/4  # Phase shift
            )
            graph.edges[(node1, node2)] = enhanced_edge

            return new_strength
        return 0.0

    # Enhance medical-related entanglements
    enhanced_strength = enhance_entanglement("p53", "cancer", 1.3)
    print(f"Enhanced p53-cancer entanglement: {enhanced_strength:.3f}")

    # 3. Quantum Coherence Optimization
    def optimize_graph_coherence(graph, target_coherence=0.8):
        """Optimize graph coherence through quantum operations."""
        current_coherence = graph.measure_coherence()
        print(f"Initial coherence: {current_coherence:.3f}")

        optimization_steps = 0
        max_steps = 50

        while current_coherence < target_coherence and optimization_steps < max_steps:
            # Apply coherence-preserving transformations
            for node_id in graph.nodes:
                node_state = graph.get_node_state(node_id)

                # Apply decoherence correction
                corrected_state = node_state / np.linalg.norm(node_state)
                graph.set_node_state(node_id, corrected_state)

            # Recompute coherence
            current_coherence = graph.measure_coherence()
            optimization_steps += 1

        print(f"Optimized coherence: {current_coherence:.3f} in {optimization_steps} steps")
        return current_coherence

    # Optimize graph coherence
    final_coherence = optimize_graph_coherence(multi_domain_graph, 0.75)

# Apply advanced quantum operations
advanced_quantum_operations(multi_domain_graph)

Quantum Algorithm Implementation

Implement advanced quantum algorithms for knowledge reasoning:

def implement_quantum_algorithms(graph):
    """Implement advanced quantum algorithms for knowledge reasoning."""

    inference = QuantumInference(graph)

    # 1. Quantum Page Rank Algorithm
    def quantum_pagerank(damping_factor=0.85, max_iterations=100, tolerance=1e-6):
        """Quantum version of PageRank algorithm."""

        n_nodes = len(graph.nodes)
        node_list = list(graph.nodes.keys())

        # Initialize quantum PageRank vector
        qpr_vector = np.ones(n_nodes, dtype=complex) / np.sqrt(n_nodes)

        # Create quantum transition matrix
        transition_matrix = np.zeros((n_nodes, n_nodes), dtype=complex)

        for i, source in enumerate(node_list):
            out_edges = [edge for (src, _), edge in graph.edges.items() if src == source]
            if out_edges:
                for (src, target), edge in graph.edges.items():
                    if src == source:
                        j = node_list.index(target)
                        # Quantum transition probability with entanglement
                        transition_matrix[j, i] = edge.entanglement_strength / len(out_edges)
            else:
                # Handle dangling nodes with uniform distribution
                transition_matrix[:, i] = 1.0 / n_nodes

        # Apply quantum PageRank iterations
        for iteration in range(max_iterations):
            new_qpr = (damping_factor * transition_matrix @ qpr_vector + 
                      (1 - damping_factor) / n_nodes * np.ones(n_nodes, dtype=complex))

            # Normalize quantum state
            new_qpr = new_qpr / np.linalg.norm(new_qpr)

            # Check convergence
            if np.linalg.norm(new_qpr - qpr_vector) < tolerance:
                break

            qpr_vector = new_qpr

        # Return quantum PageRank scores
        qpr_scores = {node_list[i]: abs(qpr_vector[i])**2 for i in range(n_nodes)}
        return sorted(qpr_scores.items(), key=lambda x: x[1], reverse=True)

    # Compute quantum PageRank
    qpr_results = quantum_pagerank()
    print("Top 5 nodes by Quantum PageRank:")
    for node, score in qpr_results[:5]:
        print(f"  {node}: {score:.4f}")

    # 2. Quantum Community Detection
    def quantum_community_detection(n_communities=3):
        """Detect communities using quantum spectral clustering."""

        # Create quantum Laplacian matrix
        n_nodes = len(graph.nodes)
        node_list = list(graph.nodes.keys())

        # Adjacency matrix with quantum weights
        adj_matrix = np.zeros((n_nodes, n_nodes))
        for i, source in enumerate(node_list):
            for j, target in enumerate(node_list):
                if (source, target) in graph.edges:
                    edge = graph.edges[(source, target)]
                    adj_matrix[i, j] = edge.entanglement_strength

        # Quantum Laplacian
        degree_matrix = np.diag(np.sum(adj_matrix, axis=1))
        laplacian = degree_matrix - adj_matrix

        # Compute eigenvectors for clustering
        eigenvals, eigenvecs = la.eigh(laplacian)

        # Use smallest eigenvectors for clustering
        clustering_features = eigenvecs[:, :n_communities]

        # Apply k-means clustering
        from sklearn.cluster import KMeans
        kmeans = KMeans(n_clusters=n_communities, random_state=42)
        communities = kmeans.fit_predict(clustering_features)

        # Create community mapping
        community_mapping = {node_list[i]: int(communities[i]) for i in range(n_nodes)}
        return community_mapping

    # Detect quantum communities
    communities = quantum_community_detection(4)

    print("\nQuantum Community Structure:")
    for community_id in range(4):
        members = [node for node, comm in communities.items() if comm == community_id]
        print(f"  Community {community_id}: {', '.join(members[:5])}")  # Show first 5 members

    # 3. Quantum Link Prediction with Interference
    def quantum_link_prediction_with_interference(threshold=0.4):
        """Advanced link prediction using quantum interference patterns."""

        predictions = []
        node_list = list(graph.nodes.keys())

        for i, source in enumerate(node_list):
            for j, target in enumerate(node_list[i+1:], i+1):
                if (source, target) not in graph.edges and (target, source) not in graph.edges:

                    # Compute quantum interference score
                    source_state = graph.get_node_state(source)
                    target_state = graph.get_node_state(target)

                    # Quantum interference amplitude
                    interference_amplitude = np.vdot(source_state, target_state)
                    interference_score = abs(interference_amplitude)**2

                    # Factor in neighborhood overlap
                    source_neighbors = set(target for (src, target) in graph.edges if src == source)
                    target_neighbors = set(target for (src, target) in graph.edges if src == target)

                    common_neighbors = len(source_neighbors & target_neighbors)
                    total_neighbors = len(source_neighbors | target_neighbors)

                    if total_neighbors > 0:
                        neighborhood_score = common_neighbors / total_neighbors
                    else:
                        neighborhood_score = 0.0

                    # Combined quantum prediction score
                    prediction_score = 0.7 * interference_score + 0.3 * neighborhood_score

                    if prediction_score > threshold:
                        predictions.append((source, target, prediction_score, interference_score))

        return sorted(predictions, key=lambda x: x[2], reverse=True)

    # Predict quantum links
    link_predictions = quantum_link_prediction_with_interference(0.3)

    print(f"\nTop Quantum Link Predictions:")
    for source, target, score, interference in link_predictions[:5]:
        print(f"  {source} -> {target}: {score:.3f} (interference: {interference:.3f})")

# Run advanced quantum algorithms
implement_quantum_algorithms(multi_domain_graph)

Advanced Query Processing

Multi-Modal Query Fusion

Implement sophisticated query processing with quantum superposition:

from qekgr import EntangledQueryEngine

def advanced_query_processing(graph):
    """Demonstrate advanced query processing techniques."""

    query_engine = EntangledQueryEngine(graph)

    # 1. Multi-Modal Query Fusion
    def process_multimodal_query(text_query, concept_filters, semantic_weights):
        """Process queries that combine text, concepts, and semantic constraints."""

        # Primary text query
        text_results = query_engine.query(text_query, max_results=10)

        # Concept-based filtering
        concept_results = []
        for concept in concept_filters:
            concept_matches = query_engine.semantic_search(concept, max_results=5)
            concept_results.extend(concept_matches)

        # Fusion using quantum superposition
        fused_results = []
        all_nodes = set()

        # Collect all candidate nodes
        for result in text_results:
            all_nodes.update(result.answer_nodes)

        for result in concept_results:
            all_nodes.add(result.node_id)

        # Score fusion with quantum interference
        for node in all_nodes:
            text_score = 0.0
            concept_score = 0.0

            # Text relevance score
            for result in text_results:
                if node in result.answer_nodes:
                    text_score = max(text_score, result.confidence_score)

            # Concept relevance score
            for result in concept_results:
                if result.node_id == node:
                    concept_score = max(concept_score, result.relevance_score)

            # Quantum interference fusion
            interference_factor = np.sqrt(text_score * concept_score)
            fused_score = (semantic_weights['text'] * text_score + 
                          semantic_weights['concept'] * concept_score + 
                          semantic_weights['interference'] * interference_factor)

            if fused_score > 0.2:
                fused_results.append((node, fused_score, text_score, concept_score))

        return sorted(fused_results, key=lambda x: x[1], reverse=True)

    # Example multi-modal query
    multimodal_results = process_multimodal_query(
        text_query="What treats cancer?",
        concept_filters=["drug", "therapy", "treatment"],
        semantic_weights={'text': 0.4, 'concept': 0.4, 'interference': 0.2}
    )

    print("Multi-modal Query Results:")
    for node, fused_score, text_score, concept_score in multimodal_results[:5]:
        print(f"  {node}: fused={fused_score:.3f}, text={text_score:.3f}, concept={concept_score:.3f}")

    # 2. Temporal Query Processing
    def temporal_quantum_query(query, time_weights, temporal_decay=0.1):
        """Process queries with temporal quantum evolution."""

        # Get base query results
        base_results = query_engine.query(query, max_results=15)

        # Apply temporal quantum evolution
        temporal_results = []

        for result in base_results:
            for node in result.answer_nodes:
                node_state = graph.get_node_state(node)

                # Simulate temporal evolution using quantum dynamics
                time_evolution_operator = np.exp(-1j * temporal_decay * np.random.rand())
                evolved_state = time_evolution_operator * node_state

                # Compute temporal relevance
                temporal_amplitude = np.vdot(node_state, evolved_state)
                temporal_score = abs(temporal_amplitude)**2

                # Weight by time preferences
                weighted_score = result.confidence_score * temporal_score

                temporal_results.append((node, weighted_score, temporal_score))

        return sorted(temporal_results, key=lambda x: x[1], reverse=True)

    # Example temporal query
    temporal_results = temporal_quantum_query(
        "Recent cancer treatments",
        time_weights={'recent': 0.8, 'established': 0.2}
    )

    print("\nTemporal Query Results:")
    for node, weighted_score, temporal_score in temporal_results[:5]:
        print(f"  {node}: score={weighted_score:.3f}, temporal={temporal_score:.3f}")

    # 3. Uncertainty-Aware Query Processing
    def uncertainty_aware_query(query, confidence_threshold=0.6):
        """Process queries with quantum uncertainty quantification."""

        # Get query results with uncertainty estimation
        results = query_engine.query(query, max_results=20)

        uncertainty_results = []

        for result in results:
            # Estimate uncertainty from quantum state variance
            answer_states = []
            for node in result.answer_nodes:
                node_state = graph.get_node_state(node)
                answer_states.append(node_state)

            if answer_states:
                # Compute state variance as uncertainty measure
                mean_state = np.mean(answer_states, axis=0)
                variance = np.mean([np.linalg.norm(state - mean_state)**2 
                                  for state in answer_states])

                uncertainty = np.sqrt(variance)
                confidence = result.confidence_score * (1 - uncertainty)

                if confidence > confidence_threshold:
                    uncertainty_results.append((
                        result.answer_nodes, 
                        confidence, 
                        uncertainty,
                        result.reasoning_path
                    ))

        return sorted(uncertainty_results, key=lambda x: x[1], reverse=True)

    # Example uncertainty-aware query
    uncertainty_results = uncertainty_aware_query(
        "What proteins are involved in cancer?",
        confidence_threshold=0.5
    )

    print("\nUncertainty-Aware Query Results:")
    for answers, confidence, uncertainty, reasoning in uncertainty_results[:3]:
        print(f"  Answers: {', '.join(answers)}")
        print(f"    Confidence: {confidence:.3f}, Uncertainty: {uncertainty:.3f}")
        print(f"    Reasoning: {reasoning}")

# Run advanced query processing
advanced_query_processing(multi_domain_graph)

Performance Optimization

Quantum State Caching

Implement efficient caching for quantum computations:

import functools
from typing import Dict, Any
import hashlib

class QuantumStateCache:
    """Efficient caching system for quantum state computations."""

    def __init__(self, max_cache_size=1000):
        self.cache: Dict[str, Any] = {}
        self.max_cache_size = max_cache_size
        self.access_order = []

    def _generate_key(self, graph_state, operation, *args):
        """Generate cache key from graph state and operation."""
        # Create hash from graph state
        state_hash = hashlib.md5(str(graph_state).encode()).hexdigest()[:16]
        operation_hash = hashlib.md5(f"{operation}_{args}".encode()).hexdigest()[:16]
        return f"{state_hash}_{operation_hash}"

    def get(self, key):
        """Get cached result."""
        if key in self.cache:
            # Update access order for LRU
            self.access_order.remove(key)
            self.access_order.append(key)
            return self.cache[key]
        return None

    def set(self, key, value):
        """Cache computation result."""
        if len(self.cache) >= self.max_cache_size:
            # Remove least recently used item
            lru_key = self.access_order.pop(0)
            del self.cache[lru_key]

        self.cache[key] = value
        self.access_order.append(key)

    def cached_quantum_operation(self, operation_name):
        """Decorator for caching quantum operations."""
        def decorator(func):
            @functools.wraps(func)
            def wrapper(graph, *args, **kwargs):
                # Generate cache key
                graph_signature = f"{len(graph.nodes)}_{len(graph.edges)}"
                cache_key = self._generate_key(graph_signature, operation_name, args, tuple(kwargs.items()))

                # Check cache
                cached_result = self.get(cache_key)
                if cached_result is not None:
                    return cached_result

                # Compute and cache result
                result = func(graph, *args, **kwargs)
                self.set(cache_key, result)
                return result
            return wrapper
        return decorator

# Initialize quantum cache
quantum_cache = QuantumStateCache(max_cache_size=500)

# Apply caching to expensive operations
@quantum_cache.cached_quantum_operation("coherence_measurement")
def cached_coherence_measurement(graph):
    """Cached version of coherence measurement."""
    return graph.measure_coherence()

@quantum_cache.cached_quantum_operation("entanglement_matrix")
def cached_entanglement_matrix(graph):
    """Cached computation of full entanglement matrix."""
    nodes = list(graph.nodes.keys())
    n = len(nodes)
    matrix = np.zeros((n, n))

    for i, node1 in enumerate(nodes):
        for j, node2 in enumerate(nodes):
            if i != j:
                matrix[i, j] = graph.measure_entanglement(node1, node2)

    return matrix

# Demonstrate caching benefits
print("Testing quantum caching performance:")

import time

# Without caching
start_time = time.time()
for _ in range(10):
    coherence = multi_domain_graph.measure_coherence()
uncached_time = time.time() - start_time

# With caching
start_time = time.time()
for _ in range(10):
    coherence = cached_coherence_measurement(multi_domain_graph)
cached_time = time.time() - start_time

print(f"Uncached time: {uncached_time:.4f}s")
print(f"Cached time: {cached_time:.4f}s")
print(f"Speedup: {uncached_time/cached_time:.2f}x")

Parallel Quantum Processing

Implement parallel processing for quantum operations:

import concurrent.futures
import multiprocessing as mp
from typing import List, Callable

def parallel_quantum_processing(graph, operations: List[Callable], max_workers=None):
    """Execute quantum operations in parallel."""

    if max_workers is None:
        max_workers = min(mp.cpu_count(), len(operations))

    # Divide graph into sub-components for parallel processing
    def partition_graph(graph, n_partitions):
        """Partition graph for parallel processing."""
        nodes = list(graph.nodes.keys())
        partition_size = len(nodes) // n_partitions

        partitions = []
        for i in range(n_partitions):
            start_idx = i * partition_size
            end_idx = start_idx + partition_size if i < n_partitions - 1 else len(nodes)
            partition_nodes = nodes[start_idx:end_idx]
            partitions.append(partition_nodes)

        return partitions

    # Parallel quantum walk computation
    def parallel_quantum_walks(start_nodes, steps=10):
        """Compute quantum walks in parallel."""

        def single_quantum_walk(start_node):
            inference = QuantumInference(graph)
            return inference.quantum_walk(start_node, steps)

        with concurrent.futures.ThreadPoolExecutor(max_workers=max_workers) as executor:
            futures = [executor.submit(single_quantum_walk, node) for node in start_nodes]
            results = [future.result() for future in concurrent.futures.as_completed(futures)]

        return results

    # Parallel entanglement computation
    def parallel_entanglement_computation(node_pairs):
        """Compute entanglements for node pairs in parallel."""

        def compute_entanglement_pair(node_pair):
            node1, node2 = node_pair
            return (node1, node2, graph.measure_entanglement(node1, node2))

        with concurrent.futures.ProcessPoolExecutor(max_workers=max_workers) as executor:
            futures = [executor.submit(compute_entanglement_pair, pair) for pair in node_pairs]
            results = [future.result() for future in concurrent.futures.as_completed(futures)]

        return results

    # Example parallel operations
    nodes = list(graph.nodes.keys())

    # Parallel quantum walks
    print("Running parallel quantum walks...")
    start_time = time.time()
    walk_results = parallel_quantum_walks(nodes[:5])  # First 5 nodes
    parallel_walk_time = time.time() - start_time
    print(f"Parallel quantum walks completed in {parallel_walk_time:.3f}s")

    # Parallel entanglement computation
    print("Running parallel entanglement computation...")
    node_pairs = [(nodes[i], nodes[j]) for i in range(len(nodes)) 
                  for j in range(i+1, min(i+10, len(nodes)))]  # Limit pairs for demo

    start_time = time.time()
    entanglement_results = parallel_entanglement_computation(node_pairs[:20])
    parallel_entanglement_time = time.time() - start_time
    print(f"Parallel entanglement computation completed in {parallel_entanglement_time:.3f}s")

    return {
        'quantum_walks': walk_results,
        'entanglements': entanglement_results,
        'timing': {
            'walk_time': parallel_walk_time,
            'entanglement_time': parallel_entanglement_time
        }
    }

# Run parallel processing
parallel_results = parallel_quantum_processing(multi_domain_graph)
print(f"Computed {len(parallel_results['quantum_walks'])} quantum walks")
print(f"Computed {len(parallel_results['entanglements'])} entanglement pairs")

Advanced Visualization Techniques

Dynamic Quantum State Visualization

Create advanced visualizations for quantum state evolution:

from qekgr.utils import QuantumGraphVisualizer
import plotly.graph_objects as go
from plotly.subplots import make_subplots

def create_advanced_visualizations(graph):
    """Create sophisticated quantum visualizations."""

    visualizer = QuantumGraphVisualizer(graph)

    # 1. Quantum State Evolution Heatmap
    def create_evolution_heatmap(evolution_steps=20):
        """Create heatmap showing quantum state evolution over time."""

        nodes = list(graph.nodes.keys())[:10]  # Limit for visualization
        evolution_data = np.zeros((len(nodes), evolution_steps))

        # Simulate quantum evolution
        for step in range(evolution_steps):
            for i, node in enumerate(nodes):
                # Apply small quantum evolution
                current_state = graph.get_node_state(node)
                evolved_state = current_state * np.exp(-1j * 0.1 * step)

                # Measure probability amplitude
                probability = np.sum(np.abs(evolved_state)**2)
                evolution_data[i, step] = probability

        # Create heatmap
        fig = go.Figure(data=go.Heatmap(
            z=evolution_data,
            x=list(range(evolution_steps)),
            y=nodes,
            colorscale='Viridis',
            colorbar=dict(title="Quantum Probability")
        ))

        fig.update_layout(
            title="Quantum State Evolution Over Time",
            xaxis_title="Evolution Step",
            yaxis_title="Graph Nodes",
            height=600
        )

        return fig

    # 2. Multi-Dimensional Entanglement Visualization
    def create_entanglement_3d_surface():
        """Create 3D surface plot of entanglement landscape."""

        nodes = list(graph.nodes.keys())[:15]  # Limit for performance

        # Create entanglement surface
        x_nodes = []
        y_nodes = []
        z_entanglement = []

        for i, node1 in enumerate(nodes):
            for j, node2 in enumerate(nodes):
                if i != j:
                    entanglement = graph.measure_entanglement(node1, node2)
                    x_nodes.append(i)
                    y_nodes.append(j)
                    z_entanglement.append(entanglement)

        # Create 3D surface
        fig = go.Figure(data=[go.Scatter3d(
            x=x_nodes,
            y=y_nodes,
            z=z_entanglement,
            mode='markers',
            marker=dict(
                size=8,
                color=z_entanglement,
                colorscale='Rainbow',
                showscale=True,
                colorbar=dict(title="Entanglement Strength")
            ),
            text=[f"{nodes[x]} -> {nodes[y]}" for x, y in zip(x_nodes, y_nodes)],
            hovertemplate="<b>%{text}</b><br>Entanglement: %{z:.3f}<extra></extra>"
        )])

        fig.update_layout(
            title="3D Entanglement Landscape",
            scene=dict(
                xaxis_title="Source Node Index",
                yaxis_title="Target Node Index", 
                zaxis_title="Entanglement Strength"
            ),
            height=700
        )

        return fig

    # 3. Interactive Quantum Dashboard
    def create_quantum_dashboard():
        """Create comprehensive interactive dashboard."""

        # Create subplots
        fig = make_subplots(
            rows=2, cols=2,
            subplot_titles=("Graph Network", "Quantum States", 
                           "Entanglement Heatmap", "Community Structure"),
            specs=[[{"type": "scatter"}, {"type": "scatter"}],
                   [{"type": "heatmap"}, {"type": "scatter"}]]
        )

        # Add 2D graph network
        graph_2d = visualizer.visualize_graph_2d(layout="spring")
        for trace in graph_2d.data:
            trace.showlegend = False
            fig.add_trace(trace, row=1, col=1)

        # Add quantum state projection
        try:
            states_2d = visualizer.visualize_quantum_states_2d(method="pca")
            for trace in states_2d.data:
                trace.showlegend = False
                fig.add_trace(trace, row=1, col=2)
        except:
            # Fallback if PCA fails
            pass

        # Add entanglement heatmap
        try:
            heatmap = visualizer.visualize_entanglement_heatmap()
            for trace in heatmap.data:
                trace.showlegend = False
                fig.add_trace(trace, row=2, col=1)
        except:
            pass

        # Update layout
        fig.update_layout(
            height=800,
            title_text="Quantum Knowledge Graph Dashboard",
            showlegend=False
        )

        return fig

    # Generate visualizations
    evolution_fig = create_evolution_heatmap()
    entanglement_3d_fig = create_entanglement_3d_surface()
    dashboard_fig = create_quantum_dashboard()

    return {
        'evolution': evolution_fig,
        'entanglement_3d': entanglement_3d_fig,
        'dashboard': dashboard_fig
    }

# Create advanced visualizations
advanced_viz = create_advanced_visualizations(multi_domain_graph)

# Display visualizations
print("Advanced visualizations created:")
print("- Quantum state evolution heatmap")
print("- 3D entanglement landscape")
print("- Interactive quantum dashboard")

# Save visualizations
advanced_viz['evolution'].write_html("quantum_evolution.html")
advanced_viz['entanglement_3d'].write_html("entanglement_3d.html")
advanced_viz['dashboard'].write_html("quantum_dashboard.html")

Best Practices for Advanced Applications

Design Patterns for Quantum Knowledge Graphs

# 1. Builder Pattern for Complex Graphs
class QuantumGraphBuilder:
    """Builder pattern for constructing complex quantum graphs."""

    def __init__(self, hilbert_dim=8):
        self.graph = EntangledGraph(hilbert_dim)
        self.node_registry = {}
        self.edge_patterns = []

    def add_domain(self, domain_name, entities):
        """Add entire domain with entities."""
        for entity_id, properties in entities.items():
            node = QuantumNode(entity_id, domain=domain_name, **properties)
            self.graph.add_node(node)
            self.node_registry[entity_id] = node
        return self

    def add_relationship_pattern(self, pattern_func):
        """Add relationship pattern function."""
        self.edge_patterns.append(pattern_func)
        return self

    def apply_patterns(self):
        """Apply all relationship patterns."""
        for pattern_func in self.edge_patterns:
            pattern_func(self.graph, self.node_registry)
        return self

    def build(self):
        """Build final graph."""
        return self.graph

# 2. Strategy Pattern for Quantum Algorithms
class QuantumAlgorithmStrategy:
    """Strategy pattern for different quantum algorithms."""

    def execute(self, graph, **params):
        raise NotImplementedError

class QuantumWalkStrategy(QuantumAlgorithmStrategy):
    def execute(self, graph, start_node, steps=10):
        inference = QuantumInference(graph)
        return inference.quantum_walk(start_node, steps)

class QuantumPageRankStrategy(QuantumAlgorithmStrategy):
    def execute(self, graph, damping_factor=0.85):
        # Implementation from earlier example
        pass

# 3. Observer Pattern for Quantum State Changes
class QuantumStateObserver:
    """Observer for quantum state changes."""

    def __init__(self):
        self.observers = []

    def add_observer(self, observer):
        self.observers.append(observer)

    def notify_state_change(self, node_id, old_state, new_state):
        for observer in self.observers:
            observer.on_quantum_state_change(node_id, old_state, new_state)

class CoherenceMonitor:
    """Monitor and log coherence changes."""

    def on_quantum_state_change(self, node_id, old_state, new_state):
        coherence_change = np.linalg.norm(new_state - old_state)
        if coherence_change > 0.1:
            print(f"Significant coherence change in {node_id}: {coherence_change:.3f}")

Performance Monitoring and Debugging

Quantum State Debugging Tools

def quantum_debugging_tools(graph):
    """Advanced debugging tools for quantum graphs."""

    # 1. Quantum State Validator
    def validate_quantum_states():
        """Validate all quantum states in the graph."""
        issues = []

        for node_id, node in graph.nodes.items():
            state = graph.get_node_state(node_id)

            # Check normalization
            norm = np.linalg.norm(state)
            if abs(norm - 1.0) > 1e-6:
                issues.append(f"Node {node_id} state not normalized: {norm:.6f}")

            # Check for NaN values
            if np.any(np.isnan(state)):
                issues.append(f"Node {node_id} contains NaN values")

            # Check state dimension
            if len(state) != graph.hilbert_dim:
                issues.append(f"Node {node_id} state dimension mismatch: {len(state)} vs {graph.hilbert_dim}")

        return issues

    # 2. Entanglement Consistency Checker
    def check_entanglement_consistency():
        """Check consistency of entanglement relationships."""
        issues = []

        for (source, target), edge in graph.edges.items():
            # Check bidirectional consistency
            if (target, source) in graph.edges:
                reverse_edge = graph.edges[(target, source)]
                if abs(edge.entanglement_strength - reverse_edge.entanglement_strength) > 0.1:
                    issues.append(f"Asymmetric entanglement: {source}-{target}")

            # Check strength bounds
            if edge.entanglement_strength < 0 or edge.entanglement_strength > 1:
                issues.append(f"Invalid entanglement strength: {source}-{target}: {edge.entanglement_strength}")

        return issues

    # 3. Performance Profiler
    def profile_quantum_operations():
        """Profile performance of quantum operations."""
        import time

        operations = [
            ("measure_coherence", lambda: graph.measure_coherence()),
            ("quantum_walk", lambda: QuantumInference(graph).quantum_walk(list(graph.nodes.keys())[0], 5)),
            ("entanglement_measure", lambda: graph.measure_entanglement(*list(graph.nodes.keys())[:2]))
        ]

        performance_report = {}

        for op_name, op_func in operations:
            times = []
            for _ in range(5):  # Run 5 times for average
                start_time = time.time()
                try:
                    result = op_func()
                    end_time = time.time()
                    times.append(end_time - start_time)
                except Exception as e:
                    times.append(float('inf'))
                    print(f"Error in {op_name}: {e}")

            performance_report[op_name] = {
                'avg_time': np.mean(times),
                'std_time': np.std(times),
                'min_time': np.min(times),
                'max_time': np.max(times)
            }

        return performance_report

    # Run debugging checks
    print("=== Quantum Graph Debugging Report ===")

    state_issues = validate_quantum_states()
    if state_issues:
        print("Quantum State Issues:")
        for issue in state_issues:
            print(f"  - {issue}")
    else:
        print("✓ All quantum states valid")

    entanglement_issues = check_entanglement_consistency()
    if entanglement_issues:
        print("Entanglement Issues:")
        for issue in entanglement_issues:
            print(f"  - {issue}")
    else:
        print("✓ All entanglements consistent")

    performance_report = profile_quantum_operations()
    print("Performance Report:")
    for op_name, metrics in performance_report.items():
        print(f"  {op_name}: {metrics['avg_time']:.4f}s ± {metrics['std_time']:.4f}s")

# Run debugging tools
quantum_debugging_tools(multi_domain_graph)

Congratulations! You've mastered the advanced features of Quantum Entangled Knowledge Graphs. You can now build sophisticated quantum knowledge systems that leverage the full power of quantum mechanics for knowledge representation and reasoning! 🎓⚛️

Next, explore the Custom Tutorial to learn how to build domain-specific applications, or check out the practical Use Cases for real-world implementations.