Point in Polygon

pip.py

def point_in_polygon(point, polygon):
    """
    Point in Polygon algorithm adapted from https://stackoverflow.com/questions/217578, 
    original source: https://wrfranklin.org/Research/Short_Notes/pnpoly.html

    :param point: the point to check as an iterable of x,y coordinates (e.g. (x, y))
    :param polygon: the polygon to check against, defined as a list of points (e.g. [(x1, y1), (x2, y2)])
    :returns: True or False depending on whether the point is contained
   
    """
    point_x, point_y = point

    if point in polygon:
        return True

    min_x = max_x = polygon[0][0]
    min_y = max_y = polygon[0][1]

    for vertex in polygon:
        vertex_x, vertex_y = vertex

        min_x = min(vertex_x, min_x)
        max_x = max(vertex_x, max_x)
        min_y = min(vertex_y, min_y)
        max_y = max(vertex_y, max_y)

    if point_x < min_x or point_x > max_x or point_y < min_y or point_y > max_y:
        return False

    contained = False
    for i in range(0, len(polygon)):
        j = i + 1
        if j > len(polygon) - 1:
            break

        vertex1_x, vertex1_y = polygon[i]
        vertex2_x, vertex2_y = polygon[j]

        if (vertex1_y > point_y) != (vertex2_y > point_y) and point_x < (
            vertex2_x - vertex1_x
        ) * (point_y - vertex1_y) / (vertex2_y - vertex1_y) + vertex1_x:
            contained = not contained

    return contained