def __init__(self, topaz, wepp, data, watershed):
self.topaz = topaz
self.wepp = int(wepp)
self.data = data
self.n = len(data)
# will define these later
# a list of indices in projected, georeferenced
# raster that coorespond to the hillslope
self.indices = self.findProjectionIndices()
self.wat = None
if watershed.hdf5 is not None:
if 'wat' in watershed.hdf5.keys():
watershed.hdf5['wat']
self.wat = Wat()
self.wat.read_hdf5(self.wepp, watershed.hdf5['wat'][str(self.wepp)])
class Subcatchment:
"""
Represents a Subcatchment
"""
def __init__(self, topaz, wepp, data, watershed):
self.topaz = topaz
self.wepp = int(wepp)
self.data = data
self.n = len(data)
# will define these later
# a list of indices in projected, georeferenced
# raster that coorespond to the hillslope
self.indices = self.findProjectionIndices()
self.wat = None
if watershed.hdf5 is not None:
if 'wat' in watershed.hdf5.keys():
watershed.hdf5['wat']
self.wat = Wat()
self.wat.read_hdf5(self.wepp, watershed.hdf5['wat'][str(self.wepp)])
def __str__(self):
return 'dn: %i\nlen(data): %s'%(self.dn, self.n)
def centroid(self):
centroid = Polygon(self.data).centroid
return (centroid.x, centroid.y)
def findProjectionIndices(self):
global georefTiff
# This function is based loosely off of Frank's tests for
# gdal.RasterizeLayer.
# https://svn.osgeo.org/gdal/trunk/autotest/alg/rasterize.py
# open the reference
# we use this to find the size, projection,
# spatial reference, and geotransform to
# project the subcatchment to
ds = gdal.Open(georefTiff)
pszProjection = ds.GetProjectionRef()
if pszProjection is not None:
srs = osr.SpatialReference()
if srs.ImportFromWkt(pszProjection ) == gdal.CE_None:
pszPrettyWkt = srs.ExportToPrettyWkt(False)
geoTransform = ds.GetGeoTransform()
# initialize a new raster in memory
driver = gdal.GetDriverByName('MEM')
target_ds = driver.Create('',
ds.RasterXSize,
ds.RasterYSize,
1, gdal.GDT_Byte )
target_ds.SetGeoTransform(geoTransform)
target_ds.SetProjection(pszProjection)
# close the reference
ds = None
# Create a memory layer to rasterize from.
rast_ogr_ds = ogr.GetDriverByName('Memory') \
.CreateDataSource( 'wrk' )
rast_mem_lyr = rast_ogr_ds.CreateLayer( 'poly', srs=srs )
# Add a polygon.
coords = ','.join(['%f %f'%(lng,lat) for lng,lat in self.data])
wkt_geom = 'POLYGON((%s))'%coords
feat = ogr.Feature( rast_mem_lyr.GetLayerDefn() )
feat.SetGeometryDirectly( ogr.Geometry(wkt = wkt_geom) )
rast_mem_lyr.CreateFeature( feat )
# Run the rasterization algorithm
err = gdal.RasterizeLayer( target_ds, [1], rast_mem_lyr,
burn_values = [255] )
rast_ogr_ds = None
rast_mem_lyr = None
band = target_ds.GetRasterBand(1)
data = band.ReadAsArray()
# find nonzero indices and return
return np.nonzero(data)
