def test_get_intersection(self):
pol1 = self.generate_rect_geojson([0,0,2,1])
pol2 = self.generate_rect_geojson([1,0,3,1])
shp1 = gis_util.geojson_to_shape(pol1)
shp2 = gis_util.geojson_to_shape(pol2)
intersection = gis_util.get_intersection(shp1, shp2)
gis_util.shape_to_wkt(intersection)
def get_cracked_cells_for_stat_area(self, stat_area):
cracked_cells = []
candidates = self.cell_spatial_hash.items_for_rect(stat_area.mbr)
for icell in candidates:
intersection = gis_util.get_intersection(stat_area.shape, icell.shape)
if not intersection:
continue
intersection_area = gis_util.get_shape_area(intersection)
pct_area = intersection_area/icell.area
# Set cracked cell values in proportion to percentage
# of parent cell's area.
ccell_keyed_values = {}
icell_keyed_values = self.c_values[icell.id]
for effort_key, icell_values in icell_keyed_values.items():
ccell_values = ccell_keyed_values.setdefault(effort_key, {})
for attr, value in icell_values.items():
ccell_values[attr] = pct_area * value
cracked_cells.append(models.CrackedCell(
parent_cell=icell,
area=intersection_area,
keyed_values=ccell_keyed_values,
))
return cracked_cells
def get_stat_area_for_pos(self, lat, lon):
pos_wkt = 'POINT(%s %s)' % (lon, lat)
pnt_shp = gis_util.wkt_to_shape(pos_wkt)
candidates = self.sa_spatial_hash.items_for_point((lon,lat))
for c in candidates:
if gis_util.get_intersection(c.shape, pnt_shp):
return c
return None
def get_cell_for_pos(self, lat, lon):
"""
Get cell which contains given point, via
spatial hash.
"""
pos_wkt = 'POINT(%s %s)' % (lon, lat)
pnt_shp = gis_util.wkt_to_shape(pos_wkt)
candidates = self.cell_spatial_hash.items_for_point((lon,lat))
for c in candidates:
if gis_util.get_intersection(c.shape, pnt_shp):
return c
return None
def post_process_cells(self, log_interval=1000):
base_msg = 'Calculating cell compositions...'
self.logger.info(base_msg)
logger = self.get_section_logger('habitat_areas', base_msg)
num_cells = len(self.cells)
counter = 0
for cell in self.cells.values():
counter += 1
if (counter % log_interval) == 0:
logger.info(
" %d of %d (%.1f%%)" %
(counter, num_cells, 1.0 * counter / num_cells * 100))
composition = {}
cell.depth = 0
# Get candidate intersecting habitats.
candidate_habs = self.habs_spatial_hash.items_for_rect(cell.mbr)
for hab in candidate_habs:
intersection = gis_util.get_intersection(cell.shape, hab.shape)
if not intersection:
continue
intersection_area = gis_util.get_shape_area(
intersection,
target_crs=self.geographic_crs,
)
hab_key = (
hab.substrate_id,
hab.energy_id,
)
pct_area = intersection_area / cell.area
composition[hab_key] = composition.get(hab_key, 0) + pct_area
cell.depth += pct_area * hab.depth
cell.habitat_composition = composition
# Convert cell area to km^2.
cell.area = cell.area / (1000.0**2)
self.dao.save(cell, commit=False)
self.dao.commit()
def post_process_cells(self, log_interval=1000):
base_msg = 'Calculating cell compositions...'
self.logger.info(base_msg)
logger = self.get_section_logger('habitat_areas', base_msg)
num_cells = len(self.cells)
counter = 0
for cell in self.cells.values():
counter += 1
if (counter % log_interval) == 0:
logger.info(" %d of %d (%.1f%%)" % (
counter, num_cells, 1.0 * counter/num_cells* 100))
composition = {}
cell.depth = 0
# Get candidate intersecting habitats.
candidate_habs = self.habs_spatial_hash.items_for_rect(cell.mbr)
for hab in candidate_habs:
intersection = gis_util.get_intersection(cell.shape, hab.shape)
if not intersection:
continue
intersection_area = gis_util.get_shape_area(
intersection,
target_crs=self.geographic_crs,
)
hab_key = (hab.substrate_id, hab.energy_id,)
pct_area = intersection_area/cell.area
composition[hab_key] = composition.get(hab_key, 0) + pct_area
cell.depth += pct_area * hab.depth
cell.habitat_composition = composition
# Convert cell area to km^2.
cell.area = cell.area/(1000.0**2)
self.dao.save(cell, commit=False)
self.dao.commit()