backend/src/tests/test_main.py

@@ -53,8 +53,8 @@ def test_turckheim(client, request):    # pylint: disable=redefined-outer-name
     assert duration_minutes*0.8 < int(result['total_time']) < duration_minutes*1.2
     assert len(landmarks) > 2           # check that there is something to visit
     assert comp_time < 30, f"Computation time exceeded 30 seconds: {comp_time:.2f} seconds"
-    # assert 2==3
+    assert 2==3
-
+'''
 def test_bellecour(client, request) :   # pylint: disable=redefined-outer-name
     """
     Test n°2 : Custom test in Lyon centre to ensure proper decision making in crowded area.
@@ -214,7 +214,7 @@ def test_shopping(client, request) :   # pylint: disable=redefined-outer-name
     assert response.status_code == 200  # check for successful planning
     assert comp_time < 30, f"Computation time exceeded 30 seconds: {comp_time:.2f} seconds"
     assert duration_minutes*0.8 < int(result['total_time']) < duration_minutes*1.2
-
+'''
 
 # def test_new_trip_single_prefs(client):
 #     response = client.post(

backend/src/utils/old_optimizer.py

@@ -0,0 +1,524 @@
+import yaml, logging
+import numpy as np
+
+from scipy.optimize import linprog
+from collections import defaultdict, deque
+
+from ..structs.landmark import Landmark
+from .get_time_separation import get_time
+from ..constants import OPTIMIZER_PARAMETERS_PATH
+
+    
+
+
+
+class Optimizer:
+
+    logger = logging.getLogger(__name__)
+
+    detour: int = None              # accepted max detour time (in minutes)
+    detour_factor: float            # detour factor of straight line vs real distance in cities
+    average_walking_speed: float    # average walking speed of adult
+    max_landmarks: int              # max number of landmarks to visit
+    overshoot: float                # overshoot to allow maxtime to overflow. Optimizer is a bit restrictive
+
+
+    def __init__(self) :
+
+        # load parameters from file
+        with OPTIMIZER_PARAMETERS_PATH.open('r') as f:
+            parameters = yaml.safe_load(f)
+            self.detour_factor = parameters['detour_factor']
+            self.average_walking_speed = parameters['average_walking_speed']
+            self.max_landmarks = parameters['max_landmarks']
+            self.overshoot = parameters['overshoot']
+        
+
+
+    # Prevent the use of a particular solution
+    def prevent_config(self, resx):
+        """
+        Prevent the use of a particular solution by adding constraints to the optimization.
+
+        Args:
+            resx (list[float]): List of edge weights.
+
+        Returns:
+            tuple[list[int], list[int]]: A tuple containing a new row for constraint matrix and new value for upper bound vector.
+        """
+        
+        for i, elem in enumerate(resx):
+            resx[i] = round(elem)
+        
+        N = len(resx)               # Number of edges
+        L = int(np.sqrt(N))         # Number of landmarks
+
+        nonzeroind = np.nonzero(resx)[0]                    # the return is a little funky so I use the [0]
+        nonzero_tup = np.unravel_index(nonzeroind, (L,L))
+
+        ind_a = nonzero_tup[0].tolist()
+        vertices_visited = ind_a
+        vertices_visited.remove(0)
+
+        ones = [1]*L
+        h = [0]*N
+        for i in range(L) :
+            if i in vertices_visited :
+                h[i*L:i*L+L] = ones
+
+        return h, [len(vertices_visited)-1]
+
+
+    # Prevents the creation of the same circle (both directions)
+    def prevent_circle(self, circle_vertices: list, L: int) :
+        """
+        Prevent circular paths by by adding constraints to the optimization.
+
+        Args:
+            circle_vertices (list): List of vertices forming a circle.
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: A tuple containing a new row for constraint matrix and new value for upper bound vector.
+        """
+
+        l1 = [0]*L*L
+        l2 = [0]*L*L
+        for i, node in enumerate(circle_vertices[:-1]) :
+            next = circle_vertices[i+1]
+
+            l1[node*L + next] = 1
+            l2[next*L + node] = 1
+
+        s = circle_vertices[0]
+        g = circle_vertices[-1]
+
+        l1[g*L + s] = 1
+        l2[s*L + g] = 1
+
+        return np.vstack((l1, l2)), [0, 0]
+
+
+    def is_connected(self, resx) :
+        """
+        Determine the order of visits and detect any circular paths in the given configuration.
+
+        Args:
+            resx (list): List of edge weights.
+
+        Returns:
+            tuple[list[int], Optional[list[list[int]]]]: A tuple containing the visit order and a list of any detected circles.
+        """
+
+        # first round the results to have only 0-1 values
+        for i, elem in enumerate(resx):
+            resx[i] = round(elem)
+        
+        N = len(resx)               # length of res
+        L = int(np.sqrt(N))         # number of landmarks. CAST INTO INT but should not be a problem because N = L**2 by def.
+
+        nonzeroind = np.nonzero(resx)[0] # the return is a little funny so I use the [0]
+        nonzero_tup = np.unravel_index(nonzeroind, (L,L))
+
+        ind_a = nonzero_tup[0].tolist()
+        ind_b = nonzero_tup[1].tolist()
+
+        # Step 1: Create a graph representation
+        graph = defaultdict(list)
+        for a, b in zip(ind_a, ind_b):
+            graph[a].append(b)
+
+        # Step 2: Function to perform BFS/DFS to extract journeys
+        def get_journey(start):
+            journey_nodes = []
+            visited = set()
+            stack = deque([start])
+
+            while stack:
+                node = stack.pop()
+                if node not in visited:
+                    visited.add(node)
+                    journey_nodes.append(node)
+                    for neighbor in graph[node]:
+                        if neighbor not in visited:
+                            stack.append(neighbor)
+
+            return journey_nodes
+
+        # Step 3: Extract all journeys
+        all_journeys_nodes = []
+        visited_nodes = set()
+
+        for node in ind_a:
+            if node not in visited_nodes:
+                journey_nodes = get_journey(node)
+                all_journeys_nodes.append(journey_nodes)
+                visited_nodes.update(journey_nodes)
+
+        for l in all_journeys_nodes :
+            if 0 in l :
+                order = l
+                all_journeys_nodes.remove(l)
+                break
+
+        if len(all_journeys_nodes) == 0 :
+            return order, None
+
+        return order, all_journeys_nodes
+
+
+
+    def init_ub_dist(self, landmarks: list[Landmark], max_time: int):
+        """
+        Initialize the objective function coefficients and inequality constraints for the optimization problem.
+
+        This function computes the distances between all landmarks and stores their attractiveness to maximize sightseeing. 
+        The goal is to maximize the objective function subject to the constraints A*x < b and A_eq*x = b_eq.
+
+        Args:
+            landmarks (list[Landmark]): List of landmarks.
+            max_time (int): Maximum time of visit allowed.
+
+        Returns:
+            tuple[list[float], list[float], list[int]]: Objective function coefficients, inequality constraint coefficients, and the right-hand side of the inequality constraint.
+        """
+        
+        # Objective function coefficients. a*x1 + b*x2 + c*x3 + ...
+        c = []
+        # Coefficients of inequality constraints (left-hand side)
+        A_ub = []
+
+        for spot1 in landmarks :
+            dist_table = [0]*len(landmarks)
+            c.append(-spot1.attractiveness)
+            for j, spot2 in enumerate(landmarks) :
+                t = get_time(spot1.location, spot2.location) + spot1.duration
+                dist_table[j] = t
+            closest = sorted(dist_table)[:25]
+            for i, dist in enumerate(dist_table) :
+                if dist not in closest :
+                    dist_table[i] = 32700
+            A_ub += dist_table
+        c = c*len(landmarks)
+
+        return c, A_ub, [max_time*self.overshoot]
+
+
+    def respect_number(self, L, max_landmarks: int):
+        """
+        Generate constraints to ensure each landmark is visited only once and cap the total number of visited landmarks.
+
+        Args:
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        ones = [1]*L
+        zeros = [0]*L
+        A = ones + zeros*(L-1)
+        b = [1]
+        for i in range(L-1) :
+            h_new = zeros*i + ones + zeros*(L-1-i)
+            A = np.vstack((A, h_new))
+            b.append(1)
+
+        A = np.vstack((A, ones*L))
+        b.append(max_landmarks+1)
+
+        return A, b
+
+
+    # Constraint to not have d14 and d41 simultaneously. Does not prevent cyclic paths with more elements
+    def break_sym(self, L):
+        """
+        Generate constraints to prevent simultaneous travel between two landmarks in both directions.
+
+        Args:
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        upper_ind = np.triu_indices(L,0,L)
+
+        up_ind_x = upper_ind[0]
+        up_ind_y = upper_ind[1]
+
+        A = [0]*L*L
+        b = [1]
+
+        for i, _ in enumerate(up_ind_x[1:]) :
+            l = [0]*L*L
+            if up_ind_x[i] != up_ind_y[i] :
+                l[up_ind_x[i]*L + up_ind_y[i]] = 1
+                l[up_ind_y[i]*L + up_ind_x[i]] = 1
+
+                A = np.vstack((A,l))
+                b.append(1)
+
+        return A, b
+
+
+    def init_eq_not_stay(self, L: int): 
+        """
+        Generate constraints to prevent staying in the same position (e.g., removing d11, d22, d33, etc.).
+
+        Args:
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[list[np.ndarray], list[int]]: Equality constraint coefficients and the right-hand side of the equality constraints.
+        """
+
+        l = [0]*L*L
+
+        for i in range(L) :
+            for j in range(L) :
+                if j == i :
+                    l[j + i*L] = 1
+        
+        l = np.array(np.array(l), dtype=np.int8)
+
+        return [l], [0]
+
+
+    def respect_user_must_do(self, landmarks: list[Landmark]) :
+        """
+        Generate constraints to ensure that landmarks marked as 'must_do' are included in the optimization.
+
+        Args:
+            landmarks (list[Landmark]): List of landmarks, where some are marked as 'must_do'.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        L = len(landmarks)
+        A = [0]*L*L
+        b = [0]
+
+        for i, elem in enumerate(landmarks[1:]) :
+            if elem.must_do is True and elem.name not in ['finish', 'start']:
+                l = [0]*L*L
+                l[i*L:i*L+L] = [1]*L        # set mandatory departures from landmarks tagged as 'must_do'
+
+                A = np.vstack((A,l))
+                b.append(1)
+
+        return A, b
+    
+
+    def respect_user_must_avoid(self, landmarks: list[Landmark]) :
+        """
+        Generate constraints to ensure that landmarks marked as 'must_avoid' are skipped in the optimization.
+
+        Args:
+            landmarks (list[Landmark]): List of landmarks, where some are marked as 'must_avoid'.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        L = len(landmarks)
+        A = [0]*L*L
+        b = [0]
+
+        for i, elem in enumerate(landmarks[1:]) :
+            if elem.must_avoid is True and elem.name not in ['finish', 'start']:
+                l = [0]*L*L
+                l[i*L:i*L+L] = [1]*L        
+
+                A = np.vstack((A,l))
+                b.append(0)             # prevent departures from landmarks tagged as 'must_do'
+
+        return A, b
+
+
+    # Constraint to ensure start at start and finish at goal
+    def respect_start_finish(self, L: int):
+        """
+        Generate constraints to ensure that the optimization starts at the designated start landmark and finishes at the goal landmark.
+
+        Args:
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        l_start = [1]*L + [0]*L*(L-1)   # sets departures only for start (horizontal ones)
+        l_start[L-1] = 0                # prevents the jump from start to finish
+        l_goal = [0]*L*L                # sets arrivals only for finish (vertical ones)
+        l_L = [0]*L*(L-1) + [1]*L       # prevents arrivals at start and departures from goal
+        for k in range(L-1) :           # sets only vertical ones for goal (go to)
+            l_L[k*L] = 1
+            if k != 0 :
+                l_goal[k*L+L-1] = 1     
+
+        A = np.vstack((l_start, l_goal))
+        b = [1, 1]
+        A = np.vstack((A,l_L))
+        b.append(0)
+
+        return A, b
+
+
+    def respect_order(self, L: int): 
+        """
+        Generate constraints to tie the optimization problem together and prevent stacked ones, although this does not fully prevent circles.
+
+        Args:
+            L (int): Number of landmarks.
+
+        Returns:
+            tuple[np.ndarray, list[int]]: Inequality constraint coefficients and the right-hand side of the inequality constraints.
+        """
+
+        A = [0]*L*L
+        b = [0]
+        for i in range(L-1) :           # Prevent stacked ones
+            if i == 0 or i == L-1:      # Don't touch start or finish
+                continue
+            else : 
+                l = [0]*L
+                l[i] = -1
+                l = l*L
+                for j in range(L) :
+                    l[i*L + j] = 1
+
+                A = np.vstack((A,l))
+                b.append(0)
+
+        return A, b
+
+
+    def link_list(self, order: list[int], landmarks: list[Landmark])->list[Landmark] :
+        """
+        Compute the time to reach from each landmark to the next and create a list of landmarks with updated travel times.
+
+        Args:
+            order (list[int]): List of indices representing the order of landmarks to visit.
+            landmarks (list[Landmark]): List of all landmarks.
+
+        Returns:
+            list[Landmark]]: The updated linked list of landmarks with travel times
+        """
+        
+        L =  []
+        j = 0
+        while j < len(order)-1 :
+            # get landmarks involved
+            elem = landmarks[order[j]]
+            next = landmarks[order[j+1]]
+
+            # get attributes
+            elem.time_to_reach_next = get_time(elem.location, next.location)
+            elem.must_do = True
+            elem.location = (round(elem.location[0], 5), round(elem.location[1], 5))
+            elem.next_uuid = next.uuid
+            L.append(elem)
+            j += 1
+
+        next.location = (round(next.location[0], 5), round(next.location[1], 5))
+        next.must_do = True   
+        L.append(next)
+        
+        return L
+
+
+    # Main optimization pipeline
+    def solve_optimization(
+            self,
+            max_time: int,
+            landmarks: list[Landmark],
+            max_landmarks: int = None
+        ) -> list[Landmark]:
+        """
+        Main optimization pipeline to solve the landmark visiting problem.
+
+        This method sets up and solves a linear programming problem with constraints to find an optimal tour of landmarks,
+        considering user-defined must-visit landmarks, start and finish points, and ensuring no cycles are present.
+
+        Args:
+            max_time (int): Maximum time allowed for the tour in minutes.
+            landmarks (list[Landmark]): List of landmarks to visit.
+            max_landmarks (int): Maximum number of landmarks visited
+        Returns:
+            list[Landmark]: The optimized tour of landmarks with updated travel times, or None if no valid solution is found.
+        """
+        if max_landmarks is None :
+            max_landmarks = self.max_landmarks
+
+        L = len(landmarks)
+
+        # SET CONSTRAINTS FOR INEQUALITY
+        c, A_ub, b_ub = self.init_ub_dist(landmarks, max_time)          # Add the distances from each landmark to the other
+        A, b = self.respect_number(L, max_landmarks)                                   # Respect max number of visits (no more possible stops than landmarks). 
+        A_ub = np.vstack((A_ub, A), dtype=np.int16)
+        b_ub += b
+        A, b = self.break_sym(L)                                         # break the 'zig-zag' symmetry
+        A_ub = np.vstack((A_ub, A), dtype=np.int16)
+        b_ub += b
+
+
+        # SET CONSTRAINTS FOR EQUALITY
+        A_eq, b_eq = self.init_eq_not_stay(L)                            # Force solution not to stay in same place
+        A, b = self.respect_user_must_do(landmarks)                      # Check if there are user_defined must_see. Also takes care of start/goal
+        A_eq = np.vstack((A_eq, A), dtype=np.int8)
+        b_eq += b
+        A, b = self.respect_user_must_avoid(landmarks)                      # Check if there are user_defined must_see. Also takes care of start/goal
+        A_eq = np.vstack((A_eq, A), dtype=np.int8)
+        b_eq += b
+        A, b = self.respect_start_finish(L)                  # Force start and finish positions
+        A_eq = np.vstack((A_eq, A), dtype=np.int8)
+        b_eq += b
+        A, b = self.respect_order(L)                         # Respect order of visit (only works when max_time is limiting factor)
+        A_eq = np.vstack((A_eq, A), dtype=np.int8)
+        b_eq += b
+        
+        # SET BOUNDS FOR DECISION VARIABLE (x can only be 0 or 1)
+        x_bounds = [(0, 1)]*L*L
+
+        # Solve linear programming problem
+        res = linprog(c, A_ub=A_ub, b_ub=b_ub, A_eq=A_eq, b_eq = b_eq, bounds=x_bounds, method='highs', integrality=3)
+
+        # Raise error if no solution is found
+        if not res.success :
+            raise ArithmeticError("No solution could be found, the problem is overconstrained. Try with a longer trip (>30 minutes).")
+
+        # If there is a solution, we're good to go, just check for connectiveness
+        order, circles = self.is_connected(res.x)
+        #nodes, edges = is_connected(res.x)
+        i = 0
+        timeout = 80
+        while circles is not None and i < timeout:
+            A, b = self.prevent_config(res.x)
+            A_ub = np.vstack((A_ub, A))
+            b_ub += b
+            #A_ub, b_ub = prevent_circle(order, len(landmarks), A_ub, b_ub)
+            for circle in circles :
+                A, b = self.prevent_circle(circle, L)
+                A_eq = np.vstack((A_eq, A))
+                b_eq += b
+            res = linprog(c, A_ub=A_ub, b_ub=b_ub, A_eq=A_eq, b_eq = b_eq, bounds=x_bounds, method='highs', integrality=3)
+            if not res.success :
+                raise ArithmeticError("Solving failed because of overconstrained problem")
+                return None
+            order, circles = self.is_connected(res.x)
+            #nodes, edges = is_connected(res.x)
+            if circles is None :
+                break
+            # print(i)
+            i += 1
+        
+        if i == timeout :
+            raise TimeoutError(f"Optimization took too long. No solution found after {timeout} iterations.")
+
+        #sort the landmarks in the order of the solution
+        tour =  [landmarks[i] for i in order] 
+        
+        self.logger.debug(f"Re-optimized {i} times, score: {int(-res.fun)}")
+        return tour

backend/src/utils/optimizer.py

@@ -525,6 +525,13 @@ class Optimizer:
 
         self.logger.debug(f"Optimizing with {A_ub.shape[0]} + {A_eq.shape[0]} = {A_ub.shape[0] + A_eq.shape[0]} constraints.")
 
+        print(A_ub)
+        print('\n\n')
+        print(b_ub)
+        print('\n\n')
+        print(A_eq)
+        print('\n\n')
+        print(b_eq)
 
 
         # A, b = self.respect_user_must_do(landmarks)                      # Check if there are user_defined must_see. Also takes care of start/goal