    def generate_vector_color_map(self):
        """Generate color stops array for use with match expression in mapbox template"""
        vector_stops = []

        # if join data specified as filename or URL, parse JSON to list of Python dicts
        if type(self.data) == str:
            self.data = geojson_to_dict_list(self.data)

        # loop through features in self.data to create join-data map
        for row in self.data:
            
            # map color to JSON feature using color_property
            color = color_map(row[self.color_property], self.color_stops, self.color_default)

            # link to vector feature using data_join_property (from JSON object)
            vector_stops.append([row[self.data_join_property], color])

        return vector_stops