def make_utility_map(firemap: GeoData, flight_window: TimeWindow = TimeWindow(-np.inf, np.inf),
layer="ignition", output_layer="utility") -> GeoData:
"""Compute a utility map from a wildfire map"""
gradient = rate_of_spread_map(firemap, layer=layer, output_layer="ros")
grad_array = gradient["ros"]
grad_array[grad_array >= np.inf] = np.NaN
utility = 1 - (grad_array - np.nanmin(grad_array)) / (
np.nanmax(grad_array) - np.nanmin(grad_array))
utility[np.isnan(utility)] = 0.
utility[(firemap[layer] < flight_window.start) | (firemap[layer] > flight_window.end)] = 0.
return firemap.clone(data_array=utility, dtype=[(output_layer, 'float64')])
def empty_firemap(base_raster: GeoData, layer: str = "ignition") -> GeoData:
"""Create an empty fire map from a base raster"""
return base_raster.clone(fill_value=np.inf, dtype=[(layer, 'float64')])
def make_flat_utility_map(firemap: GeoData, flight_window: TimeWindow = TimeWindow(-np.inf, np.inf),
layer="ignition", output_layer="utility") -> GeoData:
"""Create a constant utility map"""
utility = firemap.clone(fill_value=1., dtype=[(output_layer, 'float64')])
utility[output_layer][(firemap[layer] < flight_window.start) | (firemap[layer] > flight_window.end)] = 0.
return utility