"""Coordinate utility functions.""" def coords(obj): """ Yields the coordinates from a Feature or Geometry. :param obj: A geometry or feature to extract the coordinates from. :type obj: Feature, Geometry :return: A generator with coordinate tuples from the geometry or feature. :rtype: generator """ # Handle recursive case first if 'features' in obj: for f in obj['features']: # For Python 2 compatibility # See https://www.reddit.com/r/learnpython/comments/4rc15s/yield_from_and_python_27/ # noqa: E501 for c in coords(f): yield c else: if isinstance(obj, (tuple, list)): coordinates = obj elif 'geometry' in obj: coordinates = obj['geometry']['coordinates'] else: coordinates = obj.get('coordinates', obj) for e in coordinates: if isinstance(e, (float, int)): yield tuple(coordinates) break for f in coords(e): yield f def map_coords(func, obj): """ Returns the mapped coordinates from a Geometry after applying the provided function to each dimension in tuples list (ie, linear scaling). :param func: Function to apply to individual coordinate values independently :type func: function :param obj: A geometry or feature to extract the coordinates from. :type obj: Point, LineString, MultiPoint, MultiLineString, Polygon, MultiPolygon :return: The result of applying the function to each dimension in the array. :rtype: list :raises ValueError: if the provided object is not GeoJSON. """ def tuple_func(coord): return (func(coord[0]), func(coord[1])) return map_tuples(tuple_func, obj) def map_tuples(func, obj): """ Returns the mapped coordinates from a Geometry after applying the provided function to each coordinate. :param func: Function to apply to tuples :type func: function :param obj: A geometry or feature to extract the coordinates from. :type obj: Point, LineString, MultiPoint, MultiLineString, Polygon, MultiPolygon :return: The result of applying the function to each dimension in the array. :rtype: list :raises ValueError: if the provided object is not GeoJSON. """ if obj['type'] == 'Point': coordinates = tuple(func(obj['coordinates'])) elif obj['type'] in ['LineString', 'MultiPoint']: coordinates = [tuple(func(c)) for c in obj['coordinates']] elif obj['type'] in ['MultiLineString', 'Polygon']: coordinates = [[ tuple(func(c)) for c in curve] for curve in obj['coordinates']] elif obj['type'] == 'MultiPolygon': coordinates = [[[ tuple(func(c)) for c in curve] for curve in part] for part in obj['coordinates']] elif obj['type'] in ['Feature', 'FeatureCollection', 'GeometryCollection']: return map_geometries(lambda g: map_tuples(func, g), obj) else: raise ValueError("Invalid geometry object %s" % repr(obj)) return {'type': obj['type'], 'coordinates': coordinates} def map_geometries(func, obj): """ Returns the result of passing every geometry in the given geojson object through func. :param func: Function to apply to tuples :type func: function :param obj: A geometry or feature to extract the coordinates from. :type obj: GeoJSON :return: The result of applying the function to each geometry :rtype: list :raises ValueError: if the provided object is not geojson. """ simple_types = [ 'Point', 'LineString', 'MultiPoint', 'MultiLineString', 'Polygon', 'MultiPolygon', ] if obj['type'] in simple_types: return func(obj) elif obj['type'] == 'GeometryCollection': geoms = [func(geom) if geom else None for geom in obj['geometries']] return {'type': obj['type'], 'geometries': geoms} elif obj['type'] == 'Feature': obj['geometry'] = func(obj['geometry']) if obj['geometry'] else None return obj elif obj['type'] == 'FeatureCollection': feats = [map_geometries(func, feat) for feat in obj['features']] return {'type': obj['type'], 'features': feats} else: raise ValueError("Invalid GeoJSON object %s" % repr(obj)) def generate_random(featureType, numberVertices=3, boundingBox=[-180.0, -90.0, 180.0, 90.0]): """ Generates random geojson features depending on the parameters passed through. The bounding box defaults to the world - [-180.0, -90.0, 180.0, 90.0]. The number of vertices defaults to 3. :param featureType: A geometry type :type featureType: Point, LineString, Polygon :param numberVertices: The number vertices that a linestring or polygon will have :type numberVertices: int :param boundingBox: A bounding box in which features will be restricted to :type boundingBox: list :return: The resulting random geojson object or geometry collection. :rtype: object :raises ValueError: if there is no featureType provided. """ from geojson import Point, LineString, Polygon import random import math lonMin = boundingBox[0] lonMax = boundingBox[2] def randomLon(): return random.uniform(lonMin, lonMax) latMin = boundingBox[1] latMax = boundingBox[3] def randomLat(): return random.uniform(latMin, latMax) def createPoint(): return Point((randomLon(), randomLat())) def createLine(): return LineString([createPoint() for unused in range(numberVertices)]) def createPoly(): aveRadius = 60 ctrX = 0.1 ctrY = 0.2 irregularity = clip(0.1, 0, 1) * 2 * math.pi / numberVertices spikeyness = clip(0.5, 0, 1) * aveRadius angleSteps = [] lower = (2 * math.pi / numberVertices) - irregularity upper = (2 * math.pi / numberVertices) + irregularity sum = 0 for i in range(numberVertices): tmp = random.uniform(lower, upper) angleSteps.append(tmp) sum = sum + tmp k = sum / (2 * math.pi) for i in range(numberVertices): angleSteps[i] = angleSteps[i] / k points = [] angle = random.uniform(0, 2 * math.pi) for i in range(numberVertices): r_i = clip(random.gauss(aveRadius, spikeyness), 0, 2 * aveRadius) x = ctrX + r_i * math.cos(angle) y = ctrY + r_i * math.sin(angle) points.append((int(x), int(y))) angle = angle + angleSteps[i] firstVal = points[0] points.append(firstVal) return Polygon([points]) def clip(x, min, max): if(min > max): return x elif(x < min): return min elif(x > max): return max else: return x if featureType == 'Point': return createPoint() if featureType == 'LineString': return createLine() if featureType == 'Polygon': return createPoly()