def test_polygonize(self):
"""Test if polygonize works"""
geometry = polygonize(
self.raster, threshold_min=1.0, threshold_max=1.5)
# Result is one square
self.assertTrue(geometry.isGeosValid())
self.assertFalse(geometry.isMultipart())
# noinspection PyArgumentEqualDefault
geometry = polygonize(self.raster, threshold_min=0.0)
# Result is several polygons
self.assertTrue(geometry.isGeosValid())
self.assertTrue(geometry.isMultipart())
expected = QgsVectorLayer(VECTOR_BASE + '.shp', 'test', 'ogr')
for feature in expected.getFeatures():
# the layer has one feature only
expected_geom = feature.geometry()
self.assertTrue((geometry.isGeosEqual(expected_geom)))
def run(self, layers=None):
"""Experimental impact function."""
self.validate()
self.prepare(layers)
target_field = self.target_field
road_type_field = self.parameters['road_type_field']
threshold_min = self.parameters['min threshold [m]']
threshold_max = self.parameters['max threshold [m]']
if threshold_min > threshold_max:
message = tr('''The minimal threshold is
greater then the maximal specified threshold.
Please check the values.''')
raise GetDataError(message)
# Extract data
H = self.hazard # Flood
E = self.exposure # Roads
H = H.get_layer()
E = E.get_layer()
# Get necessary width and height of raster
height = (self.requested_extent[3] -
self.requested_extent[1]) / (H.rasterUnitsPerPixelY())
height = int(height)
width = (self.requested_extent[2] -
self.requested_extent[0]) / (H.rasterUnitsPerPixelX())
width = int(width)
# Align raster extent and self.extent
raster_extent = H.dataProvider().extent()
xmin = raster_extent.xMinimum()
xmax = raster_extent.xMaximum()
ymin = raster_extent.yMinimum()
ymax = raster_extent.yMaximum()
x_delta = (xmax - xmin) / H.width()
x = xmin
for i in range(H.width()):
if abs(x - self.requested_extent[0]) < x_delta:
# We have found the aligned raster boundary
break
x += x_delta
_ = i
y_delta = (ymax - ymin) / H.height()
y = ymin
for i in range(H.width()):
if abs(y - self.requested_extent[1]) < y_delta:
# We have found the aligned raster boundary
break
y += y_delta
clip_extent = [x, y, x + width * x_delta, y + height * y_delta]
# Clip and polygonize
small_raster = clip_raster(H, width, height,
QgsRectangle(*clip_extent))
flooded_polygon = polygonize(small_raster, threshold_min,
threshold_max)
# Filter geometry and data using the extent
requested_extent = QgsRectangle(*self.requested_extent)
request = QgsFeatureRequest()
request.setFilterRect(requested_extent)
if flooded_polygon is None:
message = tr('''There are no objects
in the hazard layer with
"value">'%s'.
Please check the value or use other
extent.''' % (threshold_min, ))
raise GetDataError(message)
# Clip exposure by the extent
extent_as_polygon = QgsGeometry().fromRect(requested_extent)
line_layer = clip_by_polygon(E, extent_as_polygon)
# Find inundated roads, mark them
line_layer = split_by_polygon(line_layer,
flooded_polygon,
request,
mark_value=(target_field, 1))
# Find inundated roads, mark them
# line_layer = split_by_polygon(
# E,
# flooded_polygon,
# request,
# mark_value=(target_field, 1))
target_field_index = line_layer.dataProvider().\
fieldNameIndex(target_field)
# Generate simple impact report
epsg = get_utm_epsg(self.requested_extent[0], self.requested_extent[1])
output_crs = QgsCoordinateReferenceSystem(epsg)
transform = QgsCoordinateTransform(E.crs(), output_crs)
road_len = flooded_len = 0 # Length of roads
roads_by_type = dict() # Length of flooded roads by types
roads_data = line_layer.getFeatures()
road_type_field_index = line_layer.fieldNameIndex(road_type_field)
for road in roads_data:
attributes = road.attributes()
road_type = attributes[road_type_field_index]
if road_type.__class__.__name__ == 'QPyNullVariant':
road_type = tr('Other')
geom = road.geometry()
geom.transform(transform)
length = geom.length()
road_len += length
if road_type not in roads_by_type:
roads_by_type[road_type] = {'flooded': 0, 'total': 0}
roads_by_type[road_type]['total'] += length
if attributes[target_field_index] == 1:
flooded_len += length
roads_by_type[road_type]['flooded'] += length
table_body = self._tabulate(flooded_len, self.question, road_len,
roads_by_type)
impact_summary = Table(table_body).toNewlineFreeString()
map_title = tr('Roads inundated')
style_classes = [
dict(label=tr('Not Inundated'),
value=0,
colour='#1EFC7C',
transparency=0,
size=0.5),
dict(label=tr('Inundated'),
value=1,
colour='#F31A1C',
transparency=0,
size=0.5)
]
style_info = dict(target_field=target_field,
style_classes=style_classes,
style_type='categorizedSymbol')
# Convert QgsVectorLayer to inasafe layer and return it
line_layer = Vector(data=line_layer,
name=tr('Flooded roads'),
keywords={
'impact_summary': impact_summary,
'map_title': map_title,
'target_field': target_field
},
style_info=style_info)
self._impact = line_layer
return line_layer
def run(self, layers=None):
"""Experimental impact function."""
self.validate()
self.prepare(layers)
target_field = self.target_field
road_type_field = self.parameters['road_type_field']
threshold_min = self.parameters['min threshold [m]']
threshold_max = self.parameters['max threshold [m]']
if threshold_min > threshold_max:
message = tr('''The minimal threshold is
greater then the maximal specified threshold.
Please check the values.''')
raise GetDataError(message)
# Extract data
H = self.hazard # Flood
E = self.exposure # Roads
H = H.get_layer()
E = E.get_layer()
# Get necessary width and height of raster
height = (self.requested_extent[3] - self.requested_extent[1]) / (
H.rasterUnitsPerPixelY())
height = int(height)
width = (self.requested_extent[2] - self.requested_extent[0]) / (
H.rasterUnitsPerPixelX())
width = int(width)
# Align raster extent and self.extent
raster_extent = H.dataProvider().extent()
xmin = raster_extent.xMinimum()
xmax = raster_extent.xMaximum()
ymin = raster_extent.yMinimum()
ymax = raster_extent.yMaximum()
x_delta = (xmax - xmin) / H.width()
x = xmin
for i in range(H.width()):
if abs(x - self.requested_extent[0]) < x_delta:
# We have found the aligned raster boundary
break
x += x_delta
_ = i
y_delta = (ymax - ymin) / H.height()
y = ymin
for i in range(H.width()):
if abs(y - self.requested_extent[1]) < y_delta:
# We have found the aligned raster boundary
break
y += y_delta
clip_extent = [x, y, x + width * x_delta, y + height * y_delta]
# Clip and polygonize
small_raster = clip_raster(
H, width, height, QgsRectangle(*clip_extent))
flooded_polygon = polygonize(
small_raster, threshold_min, threshold_max)
# Filter geometry and data using the extent
requested_extent = QgsRectangle(*self.requested_extent)
request = QgsFeatureRequest()
request.setFilterRect(requested_extent)
if flooded_polygon is None:
message = tr('''There are no objects
in the hazard layer with
"value">'%s'.
Please check the value or use other
extent.''' % (threshold_min, ))
raise GetDataError(message)
# Clip exposure by the extent
extent_as_polygon = QgsGeometry().fromRect(requested_extent)
line_layer = clip_by_polygon(
E,
extent_as_polygon
)
# Find inundated roads, mark them
line_layer = split_by_polygon(
line_layer,
flooded_polygon,
request,
mark_value=(target_field, 1))
# Find inundated roads, mark them
# line_layer = split_by_polygon(
# E,
# flooded_polygon,
# request,
# mark_value=(target_field, 1))
target_field_index = line_layer.dataProvider().\
fieldNameIndex(target_field)
# Generate simple impact report
epsg = get_utm_epsg(self.requested_extent[0], self.requested_extent[1])
output_crs = QgsCoordinateReferenceSystem(epsg)
transform = QgsCoordinateTransform(E.crs(), output_crs)
road_len = flooded_len = 0 # Length of roads
roads_by_type = dict() # Length of flooded roads by types
roads_data = line_layer.getFeatures()
road_type_field_index = line_layer.fieldNameIndex(road_type_field)
for road in roads_data:
attributes = road.attributes()
road_type = attributes[road_type_field_index]
if road_type.__class__.__name__ == 'QPyNullVariant':
road_type = tr('Other')
geom = road.geometry()
geom.transform(transform)
length = geom.length()
road_len += length
if road_type not in roads_by_type:
roads_by_type[road_type] = {'flooded': 0, 'total': 0}
roads_by_type[road_type]['total'] += length
if attributes[target_field_index] == 1:
flooded_len += length
roads_by_type[road_type]['flooded'] += length
table_body = self._tabulate(flooded_len, self.question, road_len,
roads_by_type)
impact_summary = Table(table_body).toNewlineFreeString()
map_title = tr('Roads inundated')
style_classes = [dict(label=tr('Not Inundated'), value=0,
colour='#1EFC7C', transparency=0, size=0.5),
dict(label=tr('Inundated'), value=1,
colour='#F31A1C', transparency=0, size=0.5)]
style_info = dict(target_field=target_field,
style_classes=style_classes,
style_type='categorizedSymbol')
# Convert QgsVectorLayer to inasafe layer and return it
line_layer = Vector(
data=line_layer,
name=tr('Flooded roads'),
keywords={'impact_summary': impact_summary,
'map_title': map_title,
'target_field': target_field},
style_info=style_info)
self._impact = line_layer
return line_layer
