first homemade OSM

backend/src/utils/get_time_distance.py

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+"""Contains various helper functions to help with distance or score computations."""
+from math import sin, cos, sqrt, atan2, radians
+import yaml
+
+from ..constants import OPTIMIZER_PARAMETERS_PATH
+
+
+with OPTIMIZER_PARAMETERS_PATH.open('r') as f:
+    parameters = yaml.safe_load(f)
+    DETOUR_FACTOR = parameters['detour_factor']
+    AVERAGE_WALKING_SPEED = parameters['average_walking_speed']
+
+EARTH_RADIUS_KM = 6373
+
+
+def get_time(p1: tuple[float, float], p2: tuple[float, float]) -> int:
+    """
+    Calculate the time in minutes to travel from one location to another.
+
+    Args:
+        p1 (tuple[float, float]): Coordinates of the starting location.
+        p2 (tuple[float, float]): Coordinates of the destination.
+
+        Returns:
+        int: Time to travel from p1 to p2 in minutes.
+    """
+    # if p1 == p2:
+    #     return 0
+    # else:
+    # Compute the distance in km along the surface of the Earth
+    # (assume spherical Earth)
+    # this is the haversine formula, stolen from stackoverflow
+    # in order to not use any external libraries
+    lat1, lon1 = radians(p1[0]), radians(p1[1])
+    lat2, lon2 = radians(p2[0]), radians(p2[1])
+
+    dlon = lon2 - lon1
+    dlat = lat2 - lat1
+
+    a = sin(dlat / 2)**2 + cos(lat1) * cos(lat2) * sin(dlon / 2)**2
+    c = 2 * atan2(sqrt(a), sqrt(1 - a))
+
+    distance = EARTH_RADIUS_KM * c
+
+    # Consider the detour factor for average an average city
+    walk_distance = distance * DETOUR_FACTOR
+
+    # Time to walk this distance (in minutes)
+    walk_time = walk_distance / AVERAGE_WALKING_SPEED * 60
+
+    return min(round(walk_time), 32765)
+
+
+def get_distance(p1: tuple[float, float], p2: tuple[float, float]) -> int:
+    """
+    Calculate the time in minutes to travel from one location to another.
+
+    Args:
+        p1 (tuple[float, float]): Coordinates of the starting location.
+        p2 (tuple[float, float]): Coordinates of the destination.
+
+        Returns:
+        int: Time to travel from p1 to p2 in minutes.
+    """
+    if p1 == p2:
+        return 0
+    # Compute the distance in km along the surface of the Earth
+    # (assume spherical Earth)
+    # this is the haversine formula, stolen from stackoverflow
+    # in order to not use any external libraries
+    lat1, lon1 = radians(p1[0]), radians(p1[1])
+    lat2, lon2 = radians(p2[0]), radians(p2[1])
+
+    dlon = lon2 - lon1
+    dlat = lat2 - lat1
+
+    a = sin(dlat / 2)**2 + cos(lat1) * cos(lat2) * sin(dlon / 2)**2
+    c = 2 * atan2(sqrt(a), sqrt(1 - a))
+
+    return EARTH_RADIUS_KM * c