Exemplo n.º 1
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def find_short_path(aux_structures, loc1, loc2):
    """
    Return the shortest path between the two locations

    Parameters:
        aux_structures: the result of calling build_auxiliary_structures
        loc1: tuple of 2 floats: (latitude, longitude), representing the start
              location
        loc2: tuple of 2 floats: (latitude, longitude), representing the end
              location

    Returns:
        a list of (latitude, longitude) tuples representing the shortest path
        (in terms of distance) from loc1 to loc2.
    """
    location = aux_structures[1]
    final_path = []
    distance_1 = float('inf')
    distance_2 = float('inf')
    for node in location:
        distance_new = great_circle_distance(loc1, location[node])
        distance_2_new = great_circle_distance(loc2, location[node])
        if distance_new < distance_1:
            node1 = node
            distance_1 = distance_new
        if distance_2_new < distance_2:
            node2 = node
            distance_2 = distance_2_new
    path = find_short_path_nodes(aux_structures, node1, node2)
    if path == None:
        return None
    for node in path:
        final_path.append(location[node])
    return final_path
Exemplo n.º 2
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def build_auxiliary_structures(nodes_filename, ways_filename):
    """
    Create any auxiliary structures you are interested in, by reading the data
    from the given filenames (using read_osm_data)
    """
    #The datatype I will be a dict with keys of eligible node ids
    #with values containing a set of tuples of adjacent eligible nodes:
    #{node: {(id,lat,lon,distance,speed_limit)}}
    answer_dict={}
    big_nodes={}
    #for way in read_osm_data(ways_filename):
    #    print (way)
    for y in read_osm_data(nodes_filename):
        big_nodes.update({y['id']:y})
    for x in read_osm_data(ways_filename):
        if 'highway' in x['tags'].keys():    
            if x['tags']['highway'] in ALLOWED_HIGHWAY_TYPES:
                for w in range(len(x['nodes'])):
                    #find speed limit:
                    if 'maxspeed_mph' in x['tags'].keys():
                        speed=x['tags']['maxspeed_mph']
                    else:
                        speed=DEFAULT_SPEED_LIMIT_MPH[x['tags']['highway']]
                    #adds a new key if id is not in answer_dict
                    if x['nodes'][w] not in answer_dict.keys():
                        answer_dict.update({x['nodes'][w]:set()})
                    if w!=len(x['nodes'])-1:
                        #calculate distance between x['nodes'][w] and x['nodes'][w+1]
                        lat=big_nodes[x['nodes'][w+1]]['lat']
                        lon=big_nodes[x['nodes'][w+1]]['lon']
                        oth_lat=big_nodes[x['nodes'][w]]['lat']
                        oth_lon=big_nodes[x['nodes'][w]]['lon']
                        dist=great_circle_distance((lat,lon), (oth_lat,oth_lon))
                        answer_dict[x['nodes'][w]].add((x['nodes'][w+1],lat,lon,dist,speed))
                    if 'oneway' in x['tags'].keys():
                        if x['tags']['oneway']!='yes':
                            if w!=0:
                                #calculate distance between x['nodes'][w] and x['nodes'][w-1]
                                lat=big_nodes[x['nodes'][w-1]]['lat']
                                lon=big_nodes[x['nodes'][w-1]]['lon']
                                oth_lat=big_nodes[x['nodes'][w]]['lat']
                                oth_lon=big_nodes[x['nodes'][w]]['lon']
                                dist=great_circle_distance((lat,lon), (oth_lat,oth_lon))
                                answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
                    else:
                        if w!=0:
                            #calculate distance between x['nodes'][w] and x['nodes'][w-1]
                            lat=big_nodes[x['nodes'][w-1]]['lat']
                            lon=big_nodes[x['nodes'][w-1]]['lon']
                            oth_lat=big_nodes[x['nodes'][w]]['lat']
                            oth_lon=big_nodes[x['nodes'][w]]['lon']
                            dist=great_circle_distance((lat,lon), (oth_lat,oth_lon))
                            answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
    #removing any empty keys
    actual_dict={}
    for f in answer_dict.keys():
        if answer_dict[f]!=set():
            actual_dict.update({f:answer_dict[f]})
    return actual_dict
Exemplo n.º 3
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def find_fast_path(aux_structures, loc1, loc2):
    """
    Return the shortest path between the two locations, in terms of expected
    time (taking into account speed limits).

    Parameters:
        aux_structures: the result of calling build_auxiliary_structures
        loc1: tuple of 2 floats: (latitude, longitude), representing the start
              location
        loc2: tuple of 2 floats: (latitude, longitude), representing the end
              location

    Returns:
        a list of (latitude, longitude) tuples representing the shortest path
        (in terms of time) from loc1 to loc2.
    """
    location = aux_structures[1]
    final_path = []
    distance_1 = float('inf')
    distance_2 = float('inf')
    for node in location:
        distance_new = great_circle_distance(loc1, location[node])
        distance_2_new = great_circle_distance(loc2, location[node])
        if distance_new < distance_1:
            node1 = node
            distance_1 = distance_new
        if distance_2_new < distance_2:
            node2 = node
            distance_2 = distance_2_new

    considered_paths = [([node1], 0, 0)]
    previous_nodes = set()
    node_path = []
    while len(considered_paths) != 0:
        considered_paths.sort(key=lambda tup: tup[1] + tup[2])
        shortest_value = considered_paths.pop(0)
        if shortest_value[0][-1] in previous_nodes:
            continue
        if shortest_value[0][-1] == node2:
            node_path.extend(shortest_value[0])
            break
        else:
            previous_nodes.add(shortest_value[0][-1])
            for node in aux_structures[0].get(shortest_value[0][-1], {}):
                cost = aux_structures[2][shortest_value[0][-1]][node]
                if node in previous_nodes:
                    continue
                else:
                    considered_paths.append((shortest_value[0] + [node],
                                             shortest_value[1] + cost, 0))
    if len(node_path) == 0:
        return None
    for node in node_path:
        final_path.append(location[node])
    return final_path
Exemplo n.º 4
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def find_path(aux_structures, loc1, loc2, short=True):
    '''
    Finds a path from loc1 to loc2.
    '''

    n1 = find_nearest_node(loc1, aux_structures)
    n2 = find_nearest_node(loc2, aux_structures)
    agenda = [[0, 0, [n1]]]

    visited = set()

    while agenda:
        if short:
            agenda = sorted(agenda, key=lambda x: x[0])
        else:
            agenda = sorted(agenda, key=lambda x: x[1])
        popped = agenda.pop(0)
        current_path = popped[2]
        # create agenda by looping thru children of terminal node of current path
        terminal_node = current_path[-1]
        if terminal_node not in visited:
            if terminal_node == n2:  # if terminal node is destination node
                return [aux_structures[1][node] for node in current_path]
            visited.add(terminal_node)
            children_of_terminal_n = aux_structures[0][terminal_node]
            for neighbor in children_of_terminal_n:  #loop thru neighbor nodes
                if neighbor not in visited:
                    new_path = current_path.copy()
                    new_path.append(neighbor)
                    if short:
                        d = popped[1]  #distance so far
                        d += great_circle_distance(
                            (
                                aux_structures[1][neighbor]
                                [0],  #added distance of neighbor node from last node
                                aux_structures[1][neighbor][1]),
                            (aux_structures[1][terminal_node][0],
                             aux_structures[1][terminal_node][1]))

                        h = great_circle_distance(
                            aux_structures[1][neighbor],
                            aux_structures[1][n2])  # heuristic
                        agenda.append([h + d, d, new_path])
                    else:
                        t = popped[1]
                        t += great_circle_distance(
                            (aux_structures[1][neighbor][0],
                             aux_structures[1][neighbor][1]),
                            (aux_structures[1][terminal_node][0],
                             aux_structures[1][terminal_node][1]
                             )) / aux_structures[0][terminal_node][
                                 neighbor]  #finds time to new node
                        agenda.append([0, t, new_path])

    return None
Exemplo n.º 5
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def find_path(graph, loc1, loc2, short):
    def find_start_end(loc1, loc2):
        """
        Find start/end nodes near loc1/loc2, by iterating over a graph 
        of all valid nodes (those appeared on some ways); and find smallest great_circle_distance
        """
        start = end = None  # start node, end node
        min_start_distance = min_end_distance = float('inf')
        for node_id in graph:
            node_loc = graph[node_id]['loc']
            distance_start = great_circle_distance(loc1, node_loc)
            distance_end = great_circle_distance(loc2, node_loc)
            if distance_start < min_start_distance:
                start, min_start_distance = node_id, distance_start
            if distance_end < min_end_distance:
                end, min_end_distance = node_id, distance_end
        return start, end

    start, end = find_start_end(loc1, loc2)

    # find shortest/fastest path from start to end, using uniform-cost search
    agenda = [(0, [start])]  # list of tuples (cost, path)
    expanded = set()
    # pulled_agenda = 0 ## counter, comparison of using heuristic vs not-using-heuristic
    while agenda:
        # find lowest cost path currently in agenda || would be nice if i am allowed to import heapq
        # HEURISTIC
        if short:  # use heuristic
            min_cost_so_far, min_index = float('inf'), None
            for i, (cost_heuristic, path) in enumerate(agenda):
                cost_heuristic += great_circle_distance(
                    graph[path[-1]]['loc'], graph[end]['loc'])
                if cost_heuristic < min_cost_so_far:
                    min_cost_so_far, min_index = cost_heuristic, i
            path_cost, path = agenda.pop(min_index)
        else:  # not use heuristic for find_fast_path
            path_cost, path = agenda.pop(
                min(range(len(agenda)), key=agenda.__getitem__))
        # pulled_agenda += 1
        terminal = path[-1]
        if terminal not in expanded:
            if terminal == end:  # found the path, return list of tuples nodes locations: (lat, lon)
                #print(pulled_agenda)
                #return path
                return [graph[node_id]['loc'] for node_id in path]
            expanded.add(terminal)
            for adj in graph[terminal]:
                if adj not in expanded and adj in graph:
                    new_cost = great_circle_distance(graph[adj]['loc'],
                                                     graph[terminal]['loc'])
                    if not short:  # fastest path, calculate terminal->adj cost = dist/speed = time travel
                        new_cost /= graph[terminal][adj]  # speed
                    agenda.append((path_cost + new_cost, path + [adj]))
    return None
Exemplo n.º 6
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def find_short_path(aux_structures, loc1, loc2):
    """
    Return the shortest path between the two locations

    Parameters:
        aux_structures: the result of calling build_auxiliary_structures
        loc1: tuple of 2 floats: (latitude, longitude), representing the start
              location
        loc2: tuple of 2 floats: (latitude, longitude), representing the end
              location

    Returns:
        a list of (latitude, longitude) tuples representing the shortest path
        (in terms of distance) from loc1 to loc2.
    """
    Nodes, Edges, Dic = aux_structures
    nodes1 = nearest(Dic, loc1)
    nodes2 = nearest(Dic, loc2)
    agenda = [[[Nodes[nodes1]], 0, great_circle_distance(loc1, loc2)]]
    # agenda = [[[Nodes[nodes1]], 0]]
    empty = set()
    count = 0
    while agenda:
        # Remove the path with the lowest cost from the agenda.
        path = agenda.pop(0)
        count += 1
        # If this path's terminal vertex is in the expanded set,
        # ignore it completely and move on to the next path.
        if path[0][-1] in empty:
            continue
        # If this path's terminal vertex satisfies the goal condition
        # return that path. Otherwise, add its terminal vertex to the expanded set.
        if path[0][-1] == Nodes[nodes2]:
            print(count)
            return path[0]
        else:
            empty.add(path[0][-1])
        # For each of the children of that path's terminal vertex:
        id = Dic[path[0][-1]]
        for neighbor in Edges[id]:
            # If it is in the expanded set, skip it
            # Otherwise, add the associated path (and cost) to the agenda
            if Nodes[neighbor[0]] not in empty:
                p = []
                for i in path[0]:
                    p.append(i)
                p.append(Nodes[neighbor[0]])
                dis = great_circle_distance(Nodes[id], Nodes[neighbor[0]])
                h = great_circle_distance(Nodes[neighbor[0]], loc2)
                agenda.append([p, dis + path[1], h + dis + path[1]])
                # agenda.append([p, dis+path[1]])
        agenda.sort(key=lambda x: x[-1])
    return None
Exemplo n.º 7
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def find_short_path(aux_structures, loc1, loc2, n=0, oth_nodes=node_list):
    """
    Return the shortest path between the two locations

    Parameters:
        aux_structures: the result of calling build_auxiliary_structures
        loc1: tuple of 2 floats: (latitude, longitude), representing the start
              location
        loc2: tuple of 2 floats: (latitude, longitude), representing the end
              location

    Returns:
        a list of (latitude, longitude) tuples representing the shortest path
        (in terms of distance) from loc1 to loc2.
    """
    the_nodes = oth_nodes.copy()
    nodes_to_remove = set()
    for s in the_nodes:
        if not (s[0] in aux_structures.keys()):
            nodes_to_remove.add(s)
    the_nodes = the_nodes.difference(nodes_to_remove)
    min_dist1 = -1
    min_dist2 = -1
    min1 = 0
    min2 = 0
    for r in the_nodes:
        #parsing through every node to search for least distance to a node.
        one_dist = great_circle_distance((r[1], r[2]), (loc1[0], loc1[1]))
        two_dist = great_circle_distance((r[1], r[2]), (loc2[0], loc2[1]))
        if (one_dist < min_dist1) or (min_dist1 == -1):
            min_dist1 = one_dist
            min1 = r[0]
        if (two_dist < min_dist2) or (min_dist2 == -1):
            min_dist2 = two_dist
            min2 = r[0]

    #find the shortest path between these nodes
    if n != 0:
        real_path = find_short_path_nodes(aux_structures, min1, min2, 1)
    else:
        real_path = find_short_path_nodes(aux_structures, min1, min2)

    if real_path is None or len(real_path) == 1:
        return None
    #convert node ids to coordinates
    for q in the_nodes:
        if q[0] in real_path:
            the_index = real_path.index(q[0])
            new_tuple = (q[1], q[2])
            real_path.remove(q[0])
            real_path.insert(the_index, new_tuple)
    return real_path
Exemplo n.º 8
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def nearest(Dic, loc1):
    """
    Return the nearest node to loc1 in Dic
    """
    node = None
    loc = None
    # Loop over i in Dic.keys()
    for i in Dic.keys():
        if loc == None or great_circle_distance(
                loc, loc1) > great_circle_distance(i, loc1):
            # update node and loc
            node = Dic[i]
            loc = i
    return node
Exemplo n.º 9
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 def find_start_end(loc1, loc2):
     """
     Find start/end nodes near loc1/loc2, by iterating over a graph 
     of all valid nodes (those appeared on some ways); and find smallest great_circle_distance
     """
     start = end = None  # start node, end node
     min_start_distance = min_end_distance = float('inf')
     for node_id in graph:
         node_loc = graph[node_id]['loc']
         distance_start = great_circle_distance(loc1, node_loc)
         distance_end = great_circle_distance(loc2, node_loc)
         if distance_start < min_start_distance:
             start, min_start_distance = node_id, distance_start
         if distance_end < min_end_distance:
             end, min_end_distance = node_id, distance_end
     return start, end
Exemplo n.º 10
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def get_distance(node_db, node1, node2):
    ''' 
    Returns the distance in miles between two Node ids
    '''
    coord1 = node_db[node1]['coordinates']
    coord2 = node_db[node2]['coordinates']
    return great_circle_distance(coord1, coord2)
Exemplo n.º 11
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def cost_between(dist, speed, n1, n2, short=True):
    d = great_circle_distance(dist[n1], dist[n2])
    if short:
        return d
    else:
        pair = sorted_tuple(n1, n2)
        s = speed[pair]
        return d / s
Exemplo n.º 12
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def nearest_node_to_loc(node_locs, loc):
    best = float('inf')
    node = None
    for id_, nloc in node_locs.items():
        dist = great_circle_distance(loc, nloc)
        if dist < best:
            best = dist
            node = id_
    return node
Exemplo n.º 13
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def find_fast_path(aux_structures, loc1, loc2):
    """
    loc1 and loc2 are (lat, lon) tuples
    """
    node_locs, adjacency, max_speed_limit = aux_structures

    node1 = nearest_node_to_loc(node_locs, loc1)
    node2 = nearest_node_to_loc(node_locs, loc2)

    print('running search')
    path = a_star(adjacency,
                  node1,
                  node2,
                  cost_func=lambda n1, n2: great_circle_distance(
                      node_locs[n1], node_locs[n2[0]]) / n2[1],
                  heuristic=lambda node: great_circle_distance(
                      node_locs[node], node_locs[node2]) / max_speed_limit)
    return [node_locs[n] for n in path] if path is not None else None
Exemplo n.º 14
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def get_closest_node(aux_structures, loc):
    locs = aux_structures['locations']
    best = None
    min_cost = None
    for id, nloc in locs.items():
        cost = great_circle_distance(nloc, loc)
        if best is None or cost < min_cost:
            best = id
            min_cost = cost
    return best
Exemplo n.º 15
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def calculate_distance(aux_structures, start, end):
    """
    Returns the distance between two nodes.
    start and end are node IDs.
    """

    start_id_to_coordinate = map_node_id_to_coordinates(aux_structures, start)
    end_id_to_coordinate = map_node_id_to_coordinates(aux_structures, end)

    distance = great_circle_distance(start_id_to_coordinate,
                                     end_id_to_coordinate)
    return distance
Exemplo n.º 16
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def spherematch2(ra1, dec1, ra2, dec2, kdt, tolerance=1/3600., k=100):
	"""
	Uses a k-d tree to efficiently match two pairs of coordinates in spherical
	geometry, with a tolerance in degrees.
	"""
	coords1 = radec_to_coords(ra1, dec1)
	idx = kdt.query(coords1, k=k)[1].flatten()
	ds = great_circle_distance(ra1, dec1, ra2[idx], dec2[idx])
	msk = ds < tolerance
	idx = idx[msk]
	ds = ds[msk]
	return idx, ds
Exemplo n.º 17
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def spherematch2(ra1, dec1, ra2, dec2, kdt, tolerance=1 / 3600., k=100):
    """
	Uses a k-d tree to efficiently match two pairs of coordinates in spherical
	geometry, with a tolerance in degrees.
	"""
    coords1 = radec_to_coords(ra1, dec1)
    idx = kdt.query(coords1, k=k)[1].flatten()
    ds = great_circle_distance(ra1, dec1, ra2[idx], dec2[idx])
    msk = ds < tolerance
    idx = idx[msk]
    ds = ds[msk]
    return idx, ds
Exemplo n.º 18
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def cull_bad_measurements(phot_groups_filepath):

    """
	Eliminates bad measurements from the groups of measurements
	for each source. Uses a SNR cutoff and a proximity cutoff,
	such that only sources with SNR above min_snr and with centroids
	less than max_dist from the input RA/Dec position will survive.
	max_dist is in units of arcsec.
	"""

    work_dir = "/".join(phot_groups_filepath.split("/")[:-1])
    meta = json.load(open(work_dir + "/metadata.json"))

    min_snr = meta["min_snr"]
    max_dist = meta["max_dist"]

    # read in the photometry JSON files
    ch = json.load(open(phot_groups_filepath))

    # loop through the sources and look for measurements to cull
    rejected = {}
    badkeys = []
    for key in ch:
        good, bad = [], []
        for obs in ch[key]:
            ra_inp, dec_inp = obs[:2]
            ra_cnt, dec_cnt = obs[2:4]
            snr = obs[6] / obs[7]
            d = great_circle_distance(ra_inp, dec_inp, ra_cnt, dec_cnt) * 3600
            if snr > min_snr and d < max_dist:
                good.append(obs)
            else:
                bad.append(obs)
        if len(good) > 0:
            ch[key] = good
        else:
            badkeys.append(key)
        if len(bad) > 0:
            rejected[key] = bad
            # eliminate source altogether if all its measurements get culled
    for key in badkeys:
        ch.pop(key)

        # write to disk
    out_path = work_dir + "/phot_groups_culled.json"
    with open(out_path, "w") as w:
        json.dump(ch, w, indent=4 * " ")
    print("created file: " + out_path)
    out_path = work_dir + "/phot_groups_rejected.json"
    with open(out_path, "w") as w:
        json.dump(rejected, w, indent=4 * " ")
    print("created file: " + out_path)
Exemplo n.º 19
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def find_nearest_nodes(valid_ids, loc1, loc2):
    '''
    Takes two locations. Finds the nearest id to each loc by computing the
    minimum distance from loc to all our ids. Only stores the minimum 
    distance (to compare it) and the corresponding minimum id, which
    it will actualy return. Does this for both loc1 and loc2.
    '''
    inputs = [loc1, loc2]
    minimum = float('inf')
    out = []

    for value in inputs:
        for ID in valid_ids:
            location = valid_ids[ID]['location']
            if great_circle_distance(value, location) < minimum:
                minimum = great_circle_distance(value, location)
                minimum_id = ID
        out.append(minimum_id)
        minimum = float(
            'inf')  #redeclares the minimum to correctly evaluate for loc2

    return out[0], out[1]
Exemplo n.º 20
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def find_nearest_node(loc, aux_structures):
    '''
    Finds nearest node. Takes in location (lat, lon) and a dictionary of nodes_web (in aux structures)
    '''
    min_dist = float("inf")

    node_coords = aux_structures[1]  #node_id: coord
    for node in node_coords.keys():
        d = great_circle_distance((node_coords[node][0], node_coords[node][1]),
                                  loc)
        if d < min_dist:  # finds min distance from node to loc
            min_dist = d
            n1 = node
    return n1
Exemplo n.º 21
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def min_cost_heuristic(agenda, dist, goal):
    min_cost = None
    min_node = None

    for node in agenda:
        cost = agenda[node] + great_circle_distance(dist[goal], dist[node])
        if min_cost is None:
            min_cost = cost
            min_node = node
        else:
            if cost < min_cost:
                min_cost = cost
                min_node = node
    return min_node
Exemplo n.º 22
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def get_dist_cost(data, start_node_id, end_node_id):
    """
    Calculates the cost of the direct path (which is assume to exist) between
    specified start and end nodes based on the distance between them.

    Parameters:
        data: The auxiliary data structure (a dictionary) that stores information
        about nodes and the ways that connect them
        start_node_id: The integer id of the start node in data
        end_node_id: The integer id of the end node in data
    """
    p1 = get_coords(data, start_node_id)
    p2 = get_coords(data, end_node_id)
    return great_circle_distance(p1, p2)
Exemplo n.º 23
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def find_short_path_nodes(aux_structures, node1, node2):
    """
    Return the shortest path between the two nodes

    Parameters:
        aux_structures: the result of calling build_auxiliary_structures
        node1: node representing the start location
        node2: node representing the end location

    Returns:
        a list of node IDs representing the shortest path (in terms of
        distance) from node1 to node2
    """
    considered_paths = [([node1], 0, 0)]
    previous_nodes = set()
    while len(considered_paths) != 0:
        considered_paths.sort(key=lambda tup: tup[1] + tup[2])
        shortest_value = considered_paths.pop(0)
        if shortest_value[0][-1] in previous_nodes:
            continue
        if shortest_value[0][-1] == node2:
            return shortest_value[0]
        else:
            previous_nodes.add(shortest_value[0][-1])
            for node in aux_structures[0].get(shortest_value[0][-1], {}):
                loc1 = aux_structures[1][shortest_value[0][-1]]
                loc2 = aux_structures[1][node]
                cost = great_circle_distance(loc1, loc2)
                if node in previous_nodes:
                    continue
                else:
                    considered_paths.append(
                        (shortest_value[0] + [node], shortest_value[1] + cost,
                         great_circle_distance(loc2,
                                               aux_structures[1][node2])))
    return None
Exemplo n.º 24
0
def get_nearest_node(nodes_db, lat, lon):
    """ 
    Returns the nearest node that is in a relevant way
    
    Parameters:
        nodes_db: A node database which should be the first element when calling build_auxiliary_database on a database
        lat: a latitude coordinate
        lon: a longitude coordinate
    Returns:
        a node's ID that is the closest to the specified coordinate
    """
    key_min = min(
        nodes_db,
        key=lambda x: great_circle_distance(nodes_db[x]['coordinates'],
                                            (lat, lon)))
    return key_min
Exemplo n.º 25
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def get_closest_node(data, loc):
    """
    Calculates the closest node in the given dataset to a specified query location

    Parameters:
        data: The auxiliary data structure (a dictionary) that stores information
        about nodes and the ways that connect them
        loc: The query location, given in terms of a tuple of two floats (latitude, longitude)
    """
    min_dist = None
    closest = None
    for i in data:
        # Standard min-value search loop
        dist = great_circle_distance(get_coords(data, i), loc)
        if closest is None or dist < min_dist:
            closest = i
            min_dist = dist
    return closest
Exemplo n.º 26
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def find_nearest_node_id(aux_structures, loc):
    """
    Returns the node ID for the nearest node next to loc (chosen from all the valid nodes).
    loc: tuple of 2 floats: (latitude, longitude)
    """
    nodes, ways, max_speed_dic = aux_structures
    distances = {}

    # Map node IDs to distances
    for n in nodes:
        lat, lon = nodes[n]['lat'], nodes[n]['lon']
        distances[n] = great_circle_distance(loc, (lat, lon))

    # Find min distance
    min_distance = min(distances.values())

    # Get node ID with min distance
    for node_id, distance in distances.items():
        if distance == min_distance:
            return node_id
Exemplo n.º 27
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def get_nearest_node_id(aux_structures, nodes, n1):
    """
    Returns the node ID for the nearest node next to n1 from a set of nodes.
    n1: node ID.
    nodes: set containing node IDs.
    """
    id_coordinate_map = map_node_id_to_coordinates(aux_structures)
    distances = {}

    # Map node IDs to distances
    for n in nodes:
        distances[n] = great_circle_distance(loc, id_coordinate_map[n])

    # Find min distance
    min_distance = min(distances.values())

    # Get node ID with min distance
    for node_id, distance in distances.items():
        if distance == min_distance:
            return node_id
Exemplo n.º 28
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def find_nearest_loc(aux, loc1, loc2):
    dist = aux[1]

    # find n1 and n2 (nearest nodes to the given loc1 and loc2)
    d1 = None
    n1 = None

    d2 = None
    n2 = None

    for n in dist:
        if d1 is None:
            d1 = great_circle_distance(dist[n], loc1)
            n1 = n
            d2 = great_circle_distance(dist[n], loc2)
            n2 = n
        else:
            if great_circle_distance((dist[n]), loc1) < d1:
                d1 = great_circle_distance(dist[n], loc1)
                n1 = n
            if great_circle_distance((dist[n]), loc2) < d2:
                d2 = great_circle_distance(dist[n], loc2)
                n2 = n
    return n1, n2
Exemplo n.º 29
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def match_sdss(cat_path):
    for catfile in find_files(cat_path, "*merged.txt"):

        # read pipeline catalog
        print("\nreading catalog: {}".format(catfile))
        cat = pd.read_table(catfile, sep=' ')

        # retrieve SDSS data from ViZieR if not already downloaded
        ch = catfile.split('/')[-1].split('_')[1]
        outpath = catfile.replace('{}_merged.txt'.format(ch), 'sdss.vot')
        if not os.path.isfile(outpath):
            cntr_ra = np.median(cat.ra)
            cntr_dec = np.median(cat.dec)
            # get source from one corner of the mosaic to calculate radius
            c1 = (cat.ra.min(), cat.dec[cat.ra == cat.ra.min()].values[0])
            # make radius 10% bigger just to be on safe side
            radius = great_circle_distance(cntr_ra, cntr_dec, *c1) * 1.1
            url = get_url(cntr_ra, cntr_dec, radius)
            print("retrieving URL: {}".format(url))
            handler = urllib2.urlopen(url)
            raw = handler.read()
            with open(outpath, 'wb') as f:
                f.write(raw)
            print("created file: {}".format(outpath))

        # parse VOTable
        print("reading VOTable: {}".format(outpath))
        table = parse_single_table(outpath)

        # if this is one of the southern hemisphere regions, delete and continue
        if table.array.size == 0:
            os.remove(outpath)
            print("outside of SDSS coverage")
            continue

        # make sure no missing data
        for name in table.array.dtype.names:
            assert table.array[name].mask.sum() == 0

        # get unmasked array
        sdss = table.array.data

        # make sure sky coverage is big enough
        assert sdss['RAJ2000'].min() < cat.ra.min()
        assert sdss['RAJ2000'].max() > cat.ra.max()
        assert sdss['DEJ2000'].min() < cat.dec.min()
        assert sdss['DEJ2000'].max() > cat.dec.max()

        # match to catalog
        assert cat.shape[0] < sdss.shape[0]
        tol = 2 / 3600.
        idx1, idx2, ds = spherematch(cat.ra,
                                     cat.dec,
                                     sdss['RAJ2000'],
                                     sdss['DEJ2000'],
                                     tolerance=tol)
        print("matched {} out of {} sources with {} arcsec tolerance".format(
            ds.size, cat.shape[0], tol * 3600))

        # create vector of star/galaxy class (0=missing, 3=galaxy, 6=star)
        cl = np.zeros(cat.shape[0]).astype('int')
        cl[idx1] = sdss['cl'][idx2]

        # add the column to the dataset
        cat['cl'] = cl

        # write to new file
        outpath = catfile.replace('merged.txt', 'merged+sdss.txt')
        # fmt = ['%i']+['%0.8f']*2+['%.4e']*2+['%i']*2
        # hdr = ' '.join(names)+' cl'
        # np.savetxt(outpath, df.to_records(index=False), fmt=fmt, header=hdr)
        cat.to_csv(outpath, index=False, sep=' ', float_format='%.8f')
        print("created file: {}".format(outpath))
 def assert_distance(self, p1, p2, expected_distance):
     distance = great_circle_distance(p1, p2)
     self.assertAlmostEqual(expected_distance, distance)
Exemplo n.º 31
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def match_wise(cat_path, sdss=True):
    if sdss:
        search_pattern = "*merged+sdss.txt"
    else:
        search_pattern = "*merged.txt"

    for catfile in find_files(cat_path, search_pattern):

        # read pipeline catalog
        print("\nreading catalog: {}".format(catfile))
        cat = pd.read_table(catfile, sep=' ')

        # retrieve WISE data from ViZieR if not already downloaded
        ch = catfile.split('/')[-1].split('_')[1]
        if sdss:
            outpath = catfile.replace('{}_merged+sdss.txt'.format(ch),
                                      'wise.vot')
        else:
            outpath = catfile.replace('{}_merged.txt'.format(ch), 'wise.vot')
        if not os.path.isfile(outpath):
            cntr_ra = np.median(cat.ra)
            cntr_dec = np.median(cat.dec)
            # get source from one corner of the mosaic to calculate radius
            c1 = (cat.ra.min(), cat.dec[cat.ra == cat.ra.min()].values[0])
            # make radius 10% bigger just to be on safe side
            radius = great_circle_distance(cntr_ra, cntr_dec, *c1) * 1.1
            url = get_url(cntr_ra, cntr_dec, radius)
            print("retrieving URL: {}".format(url))
            handler = urllib2.urlopen(url)
            raw = handler.read()
            with open(outpath, 'wb') as f:
                f.write(raw)
            print("created file: {}".format(outpath))

        # parse VOTable
        print("reading VOTable: {}".format(outpath))
        table = parse_single_table(outpath)

        # if this is one of the southern hemisphere regions, delete and continue
        if table.array.size == 0:
            os.remove(outpath)
            print("no WISE coverage")
            continue

        # get unmasked array
        wise = table.array.data

        # make sure sky coverage is big enough
        assert wise['RAJ2000'].min() < cat.ra.min()
        assert wise['RAJ2000'].max() > cat.ra.max()
        assert wise['DEJ2000'].min() < cat.dec.min()
        assert wise['DEJ2000'].max() > cat.dec.max()

        # match to catalog
        tol = 2 / 3600.
        if cat.shape[0] < wise.shape[0]:
            idx1, idx2, ds = spherematch(cat.ra,
                                         cat.dec,
                                         wise['RAJ2000'],
                                         wise['DEJ2000'],
                                         tolerance=tol)
        else:
            idx2, idx1, ds = spherematch(wise['RAJ2000'],
                                         wise['DEJ2000'],
                                         cat.ra,
                                         cat.dec,
                                         tolerance=tol)
        print("matched {} out of {} sources with {} arcsec tolerance".format(
            ds.size, cat.shape[0], tol * 3600))

        # add WISE to the catalog
        if ch == '1':
            cat['W1mag'] = np.repeat(np.nan, cat.shape[0])
            cat['e_W1mag'] = np.repeat(np.nan, cat.shape[0])
            cat['W1mag'][idx1] = wise['W1mag'][idx2]
            cat['e_W1mag'][idx1] = wise['e_W1mag'][idx2]
        elif ch == '2':
            cat['W2mag'] = np.repeat(np.nan, cat.shape[0])
            cat['e_W2mag'] = np.repeat(np.nan, cat.shape[0])
            cat['W2mag'][idx1] = wise['W2mag'][idx2]
            cat['e_W2mag'][idx1] = wise['e_W2mag'][idx2]
        else:
            print("unexpected error adding WISE data")

        # write to new file
        outpath = catfile.replace('.txt', '+wise.csv')
        # fmt = ['%i']+['%0.8f']*2+['%.4e']*2+['%i']*2
        # hdr = ' '.join(names)+' cl'
        # np.savetxt(outpath, df.to_records(index=False), fmt=fmt, header=hdr)
        cat.to_csv(outpath, index=False, float_format='%.8f')
        print("created file: {}".format(outpath))
Exemplo n.º 32
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def match_wise(cat_path, sdss=True):
	if sdss:
		search_pattern = "*merged+sdss.txt"
	else:
		search_pattern = "*merged.txt"

	for catfile in find_files(cat_path, search_pattern):

		# read pipeline catalog
		print("\nreading catalog: {}".format(catfile))
		cat = pd.read_table(catfile, sep=' ')

		# retrieve WISE data from ViZieR if not already downloaded
		ch = catfile.split('/')[-1].split('_')[1]
		if sdss:
			outpath = catfile.replace('{}_merged+sdss.txt'.format(ch), 'wise.vot')
		else:
			outpath = catfile.replace('{}_merged.txt'.format(ch), 'wise.vot')
		if not os.path.isfile(outpath):
			cntr_ra = np.median(cat.ra)
			cntr_dec = np.median(cat.dec)
			# get source from one corner of the mosaic to calculate radius
			c1 = (cat.ra.min(), cat.dec[cat.ra==cat.ra.min()].values[0])
			# make radius 10% bigger just to be on safe side
			radius = great_circle_distance(cntr_ra, cntr_dec, *c1) * 1.1
			url = get_url(cntr_ra, cntr_dec, radius)
			print("retrieving URL: {}".format(url))
			handler = urllib2.urlopen(url)
			raw = handler.read()
			with open(outpath,'wb') as f:
				f.write(raw)
			print("created file: {}".format(outpath))

		# parse VOTable
		print("reading VOTable: {}".format(outpath))
		table = parse_single_table(outpath)

		# if this is one of the southern hemisphere regions, delete and continue
		if table.array.size == 0:
			os.remove(outpath)
			print("no WISE coverage")
			continue

		# get unmasked array
		wise = table.array.data

		# make sure sky coverage is big enough
		assert wise['RAJ2000'].min() < cat.ra.min()
		assert wise['RAJ2000'].max() > cat.ra.max()
		assert wise['DEJ2000'].min() < cat.dec.min()
		assert wise['DEJ2000'].max() > cat.dec.max()

		# match to catalog
		tol = 2/3600.
		if cat.shape[0] < wise.shape[0]:
			idx1, idx2, ds = spherematch(cat.ra, cat.dec, 
				wise['RAJ2000'], wise['DEJ2000'], tolerance = tol)
		else:
			idx2, idx1, ds = spherematch(wise['RAJ2000'], wise['DEJ2000'],
				cat.ra, cat.dec, tolerance = tol)
		print("matched {} out of {} sources with {} arcsec tolerance".format(ds.size, 
			cat.shape[0], tol*3600))

		# add WISE to the catalog
		if ch == '1':
			cat['W1mag'] = np.repeat(np.nan, cat.shape[0])
			cat['e_W1mag'] = np.repeat(np.nan, cat.shape[0])
			cat['W1mag'][idx1] = wise['W1mag'][idx2]
			cat['e_W1mag'][idx1] = wise['e_W1mag'][idx2]
		elif ch == '2':
			cat['W2mag'] = np.repeat(np.nan, cat.shape[0])
			cat['e_W2mag'] = np.repeat(np.nan, cat.shape[0])
			cat['W2mag'][idx1] = wise['W2mag'][idx2]
			cat['e_W2mag'][idx1] = wise['e_W2mag'][idx2]
		else:
			print("unexpected error adding WISE data")

		# write to new file
		outpath = catfile.replace('.txt', '+wise.csv')
		# fmt = ['%i']+['%0.8f']*2+['%.4e']*2+['%i']*2
		# hdr = ' '.join(names)+' cl'
		# np.savetxt(outpath, df.to_records(index=False), fmt=fmt, header=hdr)
		cat.to_csv(outpath, index=False, float_format='%.8f')
		print("created file: {}".format(outpath))
Exemplo n.º 33
0
def build_auxiliary_structures(nodes_filename, ways_filename):
    """
    Create any auxiliary structures you are interested in, by reading the data
    from the given filenames (using read_osm_data)
    """
    #The datatype I will be a dict with keys of eligible node ids
    #with values containing a set of tuples of adjacent eligible nodes:
    #{node: {(id,lat,lon,distance,speed_limit)}}
    answer_dict = {}
    big_nodes = {}
    list_of_nodes = set()
    for z in read_osm_data(ways_filename):
        if 'highway' in z['tags'].keys():
            if z['tags']['highway'] in ALLOWED_HIGHWAY_TYPES:
                for f in z['nodes']:
                    list_of_nodes.add(f)
    for y in read_osm_data(nodes_filename):
        if y['id'] in list_of_nodes:
            big_nodes.update({y['id']: y})
            big_tuple = (y['id'], y['lat'], y['lon'])
            node_list.add(big_tuple)
    list_of_nodes.clear()
    for x in read_osm_data(ways_filename):
        if 'highway' in x['tags'].keys():
            if x['tags']['highway'] in ALLOWED_HIGHWAY_TYPES:
                for w in range(len(x['nodes'])):
                    #find speed limit:
                    if 'maxspeed_mph' in x['tags'].keys():
                        speed = x['tags']['maxspeed_mph']
                    else:
                        speed = DEFAULT_SPEED_LIMIT_MPH[x['tags']['highway']]
                    #adds a new key if id is not in answer_dict
                    if x['nodes'][w] not in answer_dict.keys():
                        answer_dict.update({x['nodes'][w]: set()})
                    if w != len(x['nodes']) - 1:
                        #calculate distance between x['nodes'][w] and x['nodes'][w+1]
                        lat = big_nodes[x['nodes'][w + 1]]['lat']
                        lon = big_nodes[x['nodes'][w + 1]]['lon']
                        oth_lat = big_nodes[x['nodes'][w]]['lat']
                        oth_lon = big_nodes[x['nodes'][w]]['lon']
                        dist = great_circle_distance((lat, lon),
                                                     (oth_lat, oth_lon))
                        answer_dict[x['nodes'][w]].add(
                            (x['nodes'][w + 1], lat, lon, dist, speed))
                        '''
                        #to avoid duplicate reference nodes.
                        length=None
                        sonic=None
                        for f in answer_dict[x['nodes'][w]]:
                            if f[0]==x['nodes'][w+1]:
                                length=f[3]
                                sonic=f[4]
                        if length==None:
                            answer_dict[x['nodes'][w]].add((x['nodes'][w+1],lat,lon,dist,speed))
                        elif (length/sonic)>(dist/speed):
                            answer_dict[x['nodes'][w]].remove((x['nodes'][w+1],lat,lon,length,sonic))
                            answer_dict[x['nodes'][w]].add((x['nodes'][w+1],lat,lon,dist,speed))
                         '''
                    if 'oneway' in x['tags'].keys():
                        if x['tags']['oneway'] != 'yes':
                            if w != 0:
                                #calculate distance between x['nodes'][w] and x['nodes'][w-1]
                                lat = big_nodes[x['nodes'][w - 1]]['lat']
                                lon = big_nodes[x['nodes'][w - 1]]['lon']
                                oth_lat = big_nodes[x['nodes'][w]]['lat']
                                oth_lon = big_nodes[x['nodes'][w]]['lon']
                                dist = great_circle_distance(
                                    (lat, lon), (oth_lat, oth_lon))
                                answer_dict[x['nodes'][w]].add(
                                    (x['nodes'][w - 1], lat, lon, dist, speed))
                                '''
                                #to avoid duplicate reference nodes.
                                length1=None
                                sonic1=None
                                for f in answer_dict[x['nodes'][w]]:
                                    if f[0]==x['nodes'][w-1]:
                                        length1=f[3]
                                        sonic1=f[4]
                                if length1==None:
                                    answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
                                elif (length1/sonic1)>(dist/speed):
                                    answer_dict[x['nodes'][w]].remove((x['nodes'][w-1],lat,lon,length1,sonic1))
                                    answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
                                '''
                    else:
                        if w != 0:
                            #calculate distance between x['nodes'][w] and x['nodes'][w-1]
                            lat = big_nodes[x['nodes'][w - 1]]['lat']
                            lon = big_nodes[x['nodes'][w - 1]]['lon']
                            oth_lat = big_nodes[x['nodes'][w]]['lat']
                            oth_lon = big_nodes[x['nodes'][w]]['lon']
                            dist = great_circle_distance((lat, lon),
                                                         (oth_lat, oth_lon))
                            answer_dict[x['nodes'][w]].add(
                                (x['nodes'][w - 1], lat, lon, dist, speed))
                            '''
                            #to avoid duplicate reference nodes.
                            length2=None
                            sonic2=None
                            for f in answer_dict[x['nodes'][w]]:
                                if f[0]==x['nodes'][w-1]:
                                    length2=f[3]
                                    sonic2=f[4]
                            if length2==None:
                                answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
                            elif (length2/sonic2)>(dist/speed):
                                answer_dict[x['nodes'][w]].remove((x['nodes'][w-1],lat,lon,length2,sonic2))
                                answer_dict[x['nodes'][w]].add((x['nodes'][w-1],lat,lon,dist,speed))
                            '''
    big_nodes.clear()
    #removing any empty keys
    actual_dict = {}
    print(node_list)
    for f in answer_dict.keys():
        if answer_dict[f] != set():
            actual_dict.update({f: answer_dict[f]})
    answer_dict.clear()
    return actual_dict
Exemplo n.º 34
0
def gcd_heuristic(data, node1, node2):
    return great_circle_distance(get_coords(data, node1),
                                 get_coords(data, node2))
Exemplo n.º 35
0
def match_sdss(cat_path):
	for catfile in find_files(cat_path, "*merged.txt"):

		# read pipeline catalog
		print("\nreading catalog: {}".format(catfile))
		cat = pd.read_table(catfile, sep=' ')

		# retrieve SDSS data from ViZieR if not already downloaded
		ch = catfile.split('/')[-1].split('_')[1]
		outpath = catfile.replace('{}_merged.txt'.format(ch), 'sdss.vot')
		if not os.path.isfile(outpath):
			cntr_ra = np.median(cat.ra)
			cntr_dec = np.median(cat.dec)
			# get source from one corner of the mosaic to calculate radius
			c1 = (cat.ra.min(), cat.dec[cat.ra==cat.ra.min()].values[0])
			# make radius 10% bigger just to be on safe side
			radius = great_circle_distance(cntr_ra, cntr_dec, *c1) * 1.1
			url = get_url(cntr_ra, cntr_dec, radius)
			print("retrieving URL: {}".format(url))
			handler = urllib2.urlopen(url)
			raw = handler.read()
			with open(outpath,'wb') as f:
				f.write(raw)
			print("created file: {}".format(outpath))

		# parse VOTable
		print("reading VOTable: {}".format(outpath))
		table = parse_single_table(outpath)

		# if this is one of the southern hemisphere regions, delete and continue
		if table.array.size == 0:
			os.remove(outpath)
			print("outside of SDSS coverage")
			continue

		# make sure no missing data
		for name in table.array.dtype.names:
			assert table.array[name].mask.sum() == 0

		# get unmasked array
		sdss = table.array.data

		# make sure sky coverage is big enough
		assert sdss['RAJ2000'].min() < cat.ra.min()
		assert sdss['RAJ2000'].max() > cat.ra.max()
		assert sdss['DEJ2000'].min() < cat.dec.min()
		assert sdss['DEJ2000'].max() > cat.dec.max()

		# match to catalog
		assert cat.shape[0] < sdss.shape[0]
		tol = 2/3600.
		idx1, idx2, ds = spherematch(cat.ra, cat.dec, 
			sdss['RAJ2000'], sdss['DEJ2000'], tolerance = tol)
		print("matched {} out of {} sources with {} arcsec tolerance".format(ds.size, 
			cat.shape[0], tol*3600))

		# create vector of star/galaxy class (0=missing, 3=galaxy, 6=star)
		cl = np.zeros(cat.shape[0]).astype('int')
		cl[idx1] = sdss['cl'][idx2]

		# add the column to the dataset
		cat['cl'] = cl

		# write to new file
		outpath = catfile.replace('merged.txt', 'merged+sdss.txt')
		# fmt = ['%i']+['%0.8f']*2+['%.4e']*2+['%i']*2
		# hdr = ' '.join(names)+' cl'
		# np.savetxt(outpath, df.to_records(index=False), fmt=fmt, header=hdr)
		cat.to_csv(outpath, index=False, sep=' ', float_format='%.8f')
		print("created file: {}".format(outpath))
#------------------------------------------------------------------------------
angles = np.linspace(0, 2 * np.pi, image_size[0])
height = np.linspace(0, 1., image_size[1])
angle_grid, height_grid = np.meshgrid(angles, height)

#------------------------------------------------------------------------------
# Convert cylinder coordinates to spherical coordinates
#------------------------------------------------------------------------------
spherical_points = util.cylindric_to_spheric(height_grid, angle_grid)

#------------------------------------------------------------------------------
# Compute distances to each randomly generated point on the sphere
# Keep the minimal distance for each pixel
#------------------------------------------------------------------------------
dots = util.iter_dots_on_sphere(max_dot_n, dot_min_distance)
min_distances = util.great_circle_distance(spherical_points, next(dots))
for dot in dots:
    distances = util.great_circle_distance(spherical_points, dot)
    np.minimum(distances, min_distances, out=min_distances)

#------------------------------------------------------------------------------
# Use the float array to create an array of uint8, containing either black if
# the minimal distance for a given pixel to any of the points is below
# the dot_r or white otherwise
#------------------------------------------------------------------------------
black = np.zeros(image_size, dtype=np.uint8)
white = np.ones(image_size, dtype=np.uint8) * 255
spherical_projected_texture = np.where(min_distances.T < dot_r, black, white)

#------------------------------------------------------------------------------
# Save the array to an image