Esempio n. 1
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    def solve_a_new_query(self, query):

        user_u = query.obj_id
        num_edges = 0
        list_edges = []
        for user_w in self.user_mbr.iterkeys():
            if user_w == user_u:
                continue

            if not self.user_mbr.has_key(user_u):  #user_u is NEW
                if not self.graph_edges.has_key((user_u, user_w)) and \
                    MBR.is_mmb_cover(self.user_mbr[user_w], Point(query),
                                     (query.timestamp - self.last_query[user_w]) * option.MAX_SPEED):
                    num_edges += 1
                    list_edges.append((user_u, user_w))
            else:  #user_u EXISTED
                if not self.graph_edges.has_key((user_u, user_w)) and \
                    MBR.is_mmb_cover(self.user_mbr[user_w], Point(self.last_query[user_u]),
                                     (query.timestamp - self.last_query[user_w]) * option.MAX_SPEED) and \
                    MBR.is_mmb_cover(self.user_mbr[user_u], Point(self.last_query[user_w]),
                                     (query.timestamp - self.last_query[user_u]) * option.MAX_SPEED):
                    num_edges += 1
                    list_edges.append((user_u, user_w))

        print "num_edges=", num_edges
        print "list_edges - elapsed : ", (time.clock() - start_time)

        start_time = time.clock()
        graph.add_to_mc_set(list_edges)

        print "add_to_mc_set - elapsed : ", (time.clock() - start_time)
        print "mc_set =", self.mc_set
Esempio n. 2
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    def find_partial_coverage(self, part_edges, query):
        if len(part_edges) == 0:
            return []

        #binary search
        lo = 0
        hi = len(part_edges) - 1
        mid = (lo + hi) / 2
        found = False
        while True:
            if part_edges[mid][0].cur_edge_id == query.cur_edge_id:
                found = True
                break
            if part_edges[mid][0].cur_edge_id > query.cur_edge_id:
                hi = mid - 1
                if hi < lo:
                    break
            else:
                lo = mid + 1
                if lo > hi:
                    break
            mid = (lo + hi) / 2

        if found == False:
            return []

        #
        lo = mid
        while lo - 1 > 0 and part_edges[lo -
                                        1][0].cur_edge_id == query.cur_edge_id:
            lo = lo - 1
        hi = mid
        while hi + 1 < len(part_edges) and part_edges[
                hi + 1][0].cur_edge_id == query.cur_edge_id:
            hi = hi + 1

        result = []
        for pair in part_edges[lo:hi + 1]:
            if EdgeSegment.is_line_cover(Point(query), pair[0]) == True:
                result.append(pair[1])

        return result
Esempio n. 3
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    def solve_new_queries(self, timestamp):
        start_time = time.clock()

        #        mmb_list = []       #list of lists
        #        mmb_list_index = [] #list of sets
        query_list = self.query_log.frames[timestamp]

        #1. compute SC, SD, SN, (SF)
        set_F = set([])
        new_user_set = set([])

        for query in query_list:
            new_user_set = new_user_set | set([query.obj_id])

        set_C = self.user_set & new_user_set
        set_D = self.user_set - new_user_set
        set_N = new_user_set - self.user_set

        print "set_D", set_D
        print "set_N", set_N

        #2. process set_D (disappear)
        self.remove_from_mc_set(set_D)

        #3. compute_mesh_expanding (MAX_SPEED)
        for clique in self.mc_set:
            if len(clique) < option.K_ANONYMITY:
                continue

            node = list(clique)[0]
            #print "debug", clique, node

            seg_list = self.map_data.compute_mesh_expanding(
                self.user_mesh[node], option.MAX_SPEED)
            self.mmb_mesh[node] = seg_list
            for node_2 in clique:
                if node_2 != node and self.user_mc_set[
                        node_2] == self.user_mc_set[node]:
                    self.mmb_mesh[node_2] = seg_list

        #3.1
        num_edges = 0
        list_edges = []
        for node_1 in set_C:
            for node_2 in set_C:
                if node_1 != node_2 and self.mmb_mesh.has_key(
                        node_1) and self.mmb_mesh.has_key(node_2):
                    point_1 = Point(self.query_log.trajs[node_1][timestamp])
                    point_2 = Point(self.query_log.trajs[node_2][timestamp])
                    if  EdgeSegmentSet.is_set_cover(point_1, self.mmb_mesh[node_2]) and \
                        EdgeSegmentSet.is_set_cover(point_2, self.mmb_mesh[node_1]):
                        num_edges += 1
                        list_edges.append((node_1, node_2))
        print "num_edges (set_C) = ", num_edges
        graph.add_to_mc_set(list_edges)

        #3.2
        num_edges = 0
        list_edges = []
        for node_1 in set_C:
            for node_2 in set_N:
                point_2 = Point(self.query_log.trajs[node_2][timestamp])
                if self.mmb_mesh.has_key(
                        node_1) and EdgeSegmentSet.is_set_cover(
                            point_2, self.mmb_mesh[node_1]):
                    num_edges += 1
                    list_edges.append((node_1, node_2))
        print "num_edges (set_N) = ", num_edges
        graph.add_to_mc_set(list_edges)

        #4. update self.user_mc_set, self.user_mesh, self.user_set

        #4.1 compute user_mc_set, max clique for each obj_id
        self.user_mc_set = {}
        for clique in self.mc_set:
            for obj_id in clique:
                if not self.user_mc_set.has_key(obj_id):
                    self.user_mc_set[obj_id] = clique
                elif len(self.user_mc_set[obj_id]) < len(clique):
                    self.user_mc_set[obj_id] = clique
        print "Compute user_mc_set: DONE"

        #4.2 compute MMBs (CLOAKING MESHES) and self.user_set
        max_mesh_len = 0
        min_mesh_len = 1000000
        self.user_mesh = {}
        for clique in self.mc_set:
            if len(clique) >= option.K_ANONYMITY:
                locations = []
                for node in clique:
                    locations.append(self.query_log.trajs[node][timestamp])

                mesh = self.map_data.compute_mesh_mbr(
                    locations)  #TEMPORARILY !!

                #
                temp_len = EdgeSegmentSet.length(mesh)
                if max_mesh_len < temp_len:
                    max_mesh_len = temp_len
                if min_mesh_len > temp_len:
                    min_mesh_len = temp_len

                # assign mesh to all obj_id in 'clique'
                for obj_id in clique:
                    self.user_mesh[obj_id] = mesh

                #
                for obj_id in clique:
                    self.user_set = self.user_set | set([obj_id])

        print "Compute CLOAKING MESH: DONE"
        print "max_mesh_len =", max_mesh_len
        print "min_mesh_len =", min_mesh_len

        print "elapsed : ", (time.clock() - start_time)
Esempio n. 4
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    def process_existing_clique(self, clique, timestamp):

        free_nodes = []
        satisfied = True  #new clique satisfied or not

        #1. get new_loc
        expanding_list = {}  #dict of lists
        query_list = []

        for node in clique:
            query = self.query_log.trajs[node][timestamp]
            query_list.append(query)

        for query in query_list:
            seg_list = self.map_data.compute_fixed_expanding(
                query.x, query.y, query.cur_edge_id, option.INIT_DISTANCE)
            seg_list = EdgeSegmentSet.clean_fixed_expanding(seg_list)
            expanding_list[query.obj_id] = seg_list

        #2. build graph
        degree = {}
        adj = {}
        for query in query_list:
            degree[query.obj_id] = 0

        for i in range(len(query_list)):
            for j in range(i + 1, len(query_list)):
                if EdgeSegmentSet.is_set_cover(Point(query_list[i]), expanding_list[query_list[j].obj_id]) and \
                    EdgeSegmentSet.is_set_cover(Point(query_list[j]), expanding_list[query_list[i].obj_id]):
                    adj[(query_list[i].obj_id, query_list[j].obj_id)] = 1
                    adj[(query_list[j].obj_id, query_list[i].obj_id)] = 1
        for pair in adj.iterkeys():
            degree[pair[0]] += 1
            degree[pair[1]] += 1

        for node in clique:
            if degree[node] == 0:
                free_nodes.append(node)
                del expanding_list[node]
                satisfied = False

        #3. compute union (mesh) and ...
        mesh = []
        for seg_list in expanding_list.itervalues():
            mesh = EdgeSegmentSet.union(mesh, seg_list)

        #3.2 check total_len
        if EdgeSegmentSet.length(mesh) > option.MAX_MESH_LENGTH:
            satisfied = False
            # remove (heuristically) nodes which have low degrees
            while True:
                node = min(degree, degree.get)

                free_nodes.append(node)
                del degree[node]

                for node_2 in clique:
                    if adj.has_key((node, node_2)):
                        del adj[(node, node_2)]
                        del adj[(node_2, node)]
                        degree[node_2] = degree[node_2] - 1

                #re-compute union (mesh) and check total_len
                mesh = []
                for seg_list in expanding_list.itervalues():
                    mesh = EdgeSegmentSet.union(mesh, seg_list)
                if EdgeSegmentSet.length(mesh) <= option.MAX_MESH_LENGTH:
                    break

        #4. return
        return (satisfied, free_nodes, mesh)
Esempio n. 5
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    def init_mc_set(self):
        start_time = time.clock()

        expanding_list = {}  #[[]] * option.MAX_USER   #dict of lists
        query_list = self.query_log.frames[0]  #init timestamp
        min_obj_id = option.MAX_USER
        max_obj_id = 0

        #1. compute expanding_list
        for query in query_list:
            if max_obj_id < query.obj_id:
                max_obj_id = query.obj_id
            if min_obj_id > query.obj_id:
                min_obj_id = query.obj_id
            #
            self.num_user = max(self.num_user, query.obj_id)
            seg_list = self.map_data.compute_fixed_expanding(
                query.x, query.y, query.cur_edge_id, option.INIT_DISTANCE)
            seg_list = EdgeSegmentSet.clean_fixed_expanding(seg_list)

            expanding_list[query.obj_id] = seg_list

        #1.2 check connectivity of each seg_list --> OK
#        print "Connectivity check: STARTED"
#        for query in query_list:
#            if not Map.check_connected_expanding(expanding_list[query.obj_id]):
#                print "error found at obj_id=", query.obj_id
#        print "Connectivity check: DONE"

#2. init self.mc_set
        self.reset()
        for query in query_list:
            self.mc_set.append(set([query.obj_id]))

        #3. compute mc_set
        num_edges = 0
        list_edges = []
        for i in range(len(query_list)):
            for j in range(i + 1, len(query_list)):
                if get_distance(query_list[i].x, query_list[i].y, query_list[j].x, query_list[j].y) > \
                    option.INIT_DISTANCE:
                    continue

                if EdgeSegmentSet.is_set_cover(Point(query_list[i]), expanding_list[query_list[j].obj_id]) and \
                    EdgeSegmentSet.is_set_cover(Point(query_list[j]), expanding_list[query_list[i].obj_id]):
                    num_edges += 1
                    list_edges.append(
                        (query_list[i].obj_id, query_list[j].obj_id))
        print "num_edges=", num_edges
        print "list_edges - elapsed : ", (time.clock() - start_time)

        start_time = time.clock()
        graph.add_to_mc_set(list_edges)

        print "add_to_mc_set - elapsed : ", (time.clock() - start_time)
        print "mc_set =", self.mc_set

        #4. compute user_mc_set, max clique for each obj_id
        self.user_mc_set = {}
        for clique in self.mc_set:
            if len(clique) >= option.K_ANONYMITY:
                for obj_id in clique:
                    if not self.user_mc_set.has_key(obj_id):
                        self.user_mc_set[obj_id] = clique
                    elif len(self.user_mc_set[obj_id]) < len(clique):
                        self.user_mc_set[obj_id] = clique
        print "Compute user_mc_set: DONE"
        print "user_mc_set = ", self.user_mc_set

        #5. compute MMBs (CLOAKING MESHES) and self.user_set
        max_mesh_len = 0
        min_mesh_len = 1000000
        for clique in self.mc_set:
            if len(clique) >= option.K_ANONYMITY:
                mesh = []
                for obj_id in clique:
                    mesh = EdgeSegmentSet.union(mesh, expanding_list[obj_id])

                #
                temp_len = EdgeSegmentSet.length(mesh)
                if max_mesh_len < temp_len:
                    max_mesh_len = temp_len
                if min_mesh_len > temp_len:
                    min_mesh_len = temp_len

                # assign mesh to all obj_id in 'clique'
                for obj_id in clique:
                    self.user_mesh[obj_id] = mesh

                #
                for obj_id in clique:
                    self.user_set = self.user_set | set([obj_id])

        print "self.user_set = ", self.user_set

        print "Compute CLOAKING MESH: DONE"
        print "max_mesh_len =", max_mesh_len
        print "min_mesh_len =", min_mesh_len

        #5.2 check connectivity of each user_mesh --> OK
        #        start_time = time.clock()
        #        print "MMB Connectivity check: STARTED"
        #        for clique in self.mc_set:
        #            for obj_id in clique:
        #                if not Map.check_connected_expanding(self.user_mesh[obj_id]):
        #                    print "error found at clique=", clique
        #                continue
        #        print "MMB Connectivity check: DONE"
        #        print "elapsed : ", (time.clock() - start_time)

        #DEBUG
        print "len(graph.mc_set) = ", len(graph.mc_set)
        print graph.mc_set
Esempio n. 6
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    def solve_new_queries(self, timestamp):
        start_time = time.clock()

        expanding_list = {}  #dict of lists
        query_list = self.query_log.frames[timestamp]  # timestamp
        min_obj_id = option.MAX_USER
        max_obj_id = 0

        #1. compute expanding_list
        for query in query_list:
            if max_obj_id < query.obj_id:
                max_obj_id = query.obj_id
            if min_obj_id > query.obj_id:
                min_obj_id = query.obj_id
            #
            seg_list = self.map_data.compute_fixed_expanding(
                query.x, query.y, query.cur_edge_id, option.INIT_DISTANCE)
            seg_list = EdgeSegmentSet.clean_fixed_expanding(seg_list)

            expanding_list[query.obj_id] = seg_list

        #2. init self.mc_set
        self.reset()
        for query in query_list:
            self.mc_set.append(set([query.obj_id]))

        #3. compute mc_set
        start_time = time.clock()
        num_edges = 0
        list_edges = []
        for i in range(len(query_list)):
            for j in range(i + 1, len(query_list)):
                if get_distance(query_list[i].x, query_list[i].y, query_list[j].x, query_list[j].y) > \
                    option.INIT_DISTANCE:
                    continue

                if EdgeSegmentSet.is_set_cover(Point(query_list[i]), expanding_list[query_list[j].obj_id]) and \
                    EdgeSegmentSet.is_set_cover(Point(query_list[j]), expanding_list[query_list[i].obj_id]):
                    num_edges += 1
                    list_edges.append(
                        (query_list[i].obj_id, query_list[j].obj_id))
        print "num_edges=", num_edges
        print "list_edges - elapsed : ", (time.clock() - start_time)

        start_time = time.clock()
        graph.add_to_mc_set(list_edges)

        print "add_to_mc_set - elapsed : ", (time.clock() - start_time)
        print "mc_set =", self.mc_set

        #4. compute user_mc_set, max clique for each obj_id
        start_time = time.clock()
        self.user_mc_set = {}
        for clique in self.mc_set:
            if len(clique) >= option.K_ANONYMITY:
                for obj_id in clique:
                    if not self.user_mc_set.has_key(obj_id):
                        self.user_mc_set[obj_id] = clique
                    elif len(self.user_mc_set[obj_id]) < len(clique):
                        self.user_mc_set[obj_id] = clique
        print "Compute user_mc_set - elapsed : ", (time.clock() - start_time)
        print "user_mc_set = ", self.user_mc_set

        #5. compute MMBs (CLOAKING MESHES) and self.user_set
        start_time = time.clock()
        max_mesh_len = 0
        min_mesh_len = 1000000
        for clique in self.mc_set:
            if len(clique) >= option.K_ANONYMITY:
                mesh = []
                for obj_id in clique:
                    mesh = EdgeSegmentSet.union(mesh, expanding_list[obj_id])

                #
                temp_len = EdgeSegmentSet.length(mesh)
                if max_mesh_len < temp_len:
                    max_mesh_len = temp_len
                if min_mesh_len > temp_len:
                    min_mesh_len = temp_len

                # assign mesh to all obj_id in 'clique'
                for obj_id in clique:
                    self.user_mesh[obj_id] = mesh

                #
                for obj_id in clique:
                    self.user_set = self.user_set | set([obj_id])

        #print "self.user_set = ", self.user_set
        print "Compute CLOAKING MESH - elapsed : ", (time.clock() - start_time)

        print "max_mesh_len =", max_mesh_len
        print "min_mesh_len =", min_mesh_len