def test_get_sample_from_bil_info(self):
"""Test bilinear interpolation as a whole."""
from pyresample.bilinear.xarr import XArrayResamplerBilinear
resampler = XArrayResamplerBilinear(self.source_def, self.target_def,
self.radius)
_ = resampler.get_bil_info()
# Sample from data1
res = resampler.get_sample_from_bil_info(self.data1)
res = res.compute()
# Check couple of values
self.assertEqual(res.values[1, 1], 1.)
self.assertTrue(np.isnan(res.values[0, 3]))
# Check that the values haven't gone down or up a lot
self.assertAlmostEqual(np.nanmin(res.values), 1.)
self.assertAlmostEqual(np.nanmax(res.values), 1.)
# Check that dimensions are the same
self.assertEqual(res.dims, self.data1.dims)
# Sample from data1, custom fill value
res = resampler.get_sample_from_bil_info(self.data1, fill_value=-1.0)
res = res.compute()
self.assertEqual(np.nanmin(res.values), -1.)
# Sample from integer data
res = resampler.get_sample_from_bil_info(self.data1.astype(np.uint8),
fill_value=None)
res = res.compute()
# Five values should be filled with zeros, which is the
# default fill_value for integer data
self.assertEqual(np.sum(res == 0), 6)
def test_get_sample_from_bil_info(self):
"""Test bilinear interpolation as a whole."""
import dask.array as da
from xarray import DataArray
from pyresample.bilinear.xarr import XArrayResamplerBilinear
resampler = XArrayResamplerBilinear(self.source_def, self.target_def,
self.radius)
resampler.get_bil_info()
# Sample from data1
res = resampler.get_sample_from_bil_info(self.data1)
res = res.compute()
# Check couple of values
self.assertEqual(res.values[1, 1], 1.)
self.assertTrue(np.isnan(res.values[0, 3]))
# Check that the values haven't gone down or up a lot
self.assertAlmostEqual(np.nanmin(res.values), 1.)
self.assertAlmostEqual(np.nanmax(res.values), 1.)
# Check that dimensions are the same
self.assertEqual(res.dims, self.data1.dims)
# Sample from data1, custom fill value
res = resampler.get_sample_from_bil_info(self.data1, fill_value=-1.0)
res = res.compute()
self.assertEqual(np.nanmin(res.values), -1.)
# Sample from integer data
res = resampler.get_sample_from_bil_info(self.data1.astype(np.uint8),
fill_value=None)
res = res.compute()
# Five values should be filled with zeros, which is the
# default fill_value for integer data
self.assertEqual(np.sum(res == 0), 6)
# Output coordinates should have been set
self.assertTrue(isinstance(resampler._out_coords, dict))
self.assertTrue(
np.all(resampler._out_coords['x'] == resampler.out_coords_x))
self.assertTrue(
np.all(resampler._out_coords['y'] == resampler.out_coords_y))
# 3D data
data = da.moveaxis(da.dstack((self.data1, self.data1)), -1, 0)
data = DataArray(data, dims=('bands', 'y', 'x'))
res = resampler.get_sample_from_bil_info(data)
assert res.shape == (2, ) + self.target_def.shape
assert res.dims == data.dims
class BilinearResampler(BaseResampler):
"""Resample using bilinear."""
def __init__(self, source_geo_def, target_geo_def):
super(BilinearResampler, self).__init__(source_geo_def, target_geo_def)
self.resampler = None
def precompute(self, mask=None, radius_of_influence=50000, epsilon=0,
reduce_data=True, nprocs=1,
cache_dir=False, **kwargs):
"""Create bilinear coefficients and store them for later use.
Note: The `mask` keyword should be provided if geolocation may be valid
where data points are invalid. This defaults to the `mask` attribute of
the `data` numpy masked array passed to the `resample` method.
"""
del kwargs
if self.resampler is None:
kwargs = dict(source_geo_def=self.source_geo_def,
target_geo_def=self.target_geo_def,
radius_of_influence=radius_of_influence,
neighbours=32,
epsilon=epsilon,
reduce_data=reduce_data)
self.resampler = XArrayResamplerBilinear(**kwargs)
try:
self.load_bil_info(cache_dir, **kwargs)
LOG.debug("Loaded bilinear parameters")
except IOError:
LOG.debug("Computing bilinear parameters")
self.resampler.get_bil_info()
self.save_bil_info(cache_dir, **kwargs)
def load_bil_info(self, cache_dir, **kwargs):
if cache_dir:
filename = self._create_cache_filename(cache_dir,
prefix='resample_lut_bil_',
**kwargs)
cache = np.load(filename)
for elt in ['bilinear_s', 'bilinear_t', 'valid_input_index',
'index_array']:
if isinstance(cache[elt], tuple):
setattr(self.resampler, elt, cache[elt][0])
else:
setattr(self.resampler, elt, cache[elt])
cache.close()
else:
raise IOError
def save_bil_info(self, cache_dir, **kwargs):
if cache_dir:
filename = self._create_cache_filename(cache_dir,
prefix='resample_lut_bil_',
**kwargs)
LOG.info('Saving kd_tree neighbour info to %s', filename)
cache = {'bilinear_s': self.resampler.bilinear_s,
'bilinear_t': self.resampler.bilinear_t,
'valid_input_index': self.resampler.valid_input_index,
'index_array': self.resampler.index_array}
np.savez(filename, **cache)
def compute(self, data, fill_value=None, **kwargs):
"""Resample the given data using bilinear interpolation"""
del kwargs
if fill_value is None:
fill_value = data.attrs.get('_FillValue')
target_shape = self.target_geo_def.shape
res = self.resampler.get_sample_from_bil_info(data,
fill_value=fill_value,
output_shape=target_shape)
return res
class BilinearResampler(BaseResampler):
"""Resample using bilinear."""
def __init__(self, source_geo_def, target_geo_def):
"""Init BilinearResampler."""
super(BilinearResampler, self).__init__(source_geo_def, target_geo_def)
self.resampler = None
def precompute(self, mask=None, radius_of_influence=50000, epsilon=0,
reduce_data=True, cache_dir=False, **kwargs):
"""Create bilinear coefficients and store them for later use.
Note: The `mask` keyword should be provided if geolocation may be valid
where data points are invalid. This defaults to the `mask` attribute of
the `data` numpy masked array passed to the `resample` method.
"""
del kwargs
if self.resampler is None:
kwargs = dict(source_geo_def=self.source_geo_def,
target_geo_def=self.target_geo_def,
radius_of_influence=radius_of_influence,
neighbours=32,
epsilon=epsilon,
reduce_data=reduce_data)
self.resampler = XArrayResamplerBilinear(**kwargs)
try:
self.load_bil_info(cache_dir, **kwargs)
LOG.debug("Loaded bilinear parameters")
except IOError:
LOG.debug("Computing bilinear parameters")
self.resampler.get_bil_info()
self.save_bil_info(cache_dir, **kwargs)
def load_bil_info(self, cache_dir, **kwargs):
"""Load bilinear resampling info from cache directory."""
if cache_dir:
filename = self._create_cache_filename(cache_dir,
prefix='bil_lut-',
**kwargs)
for val in BIL_COORDINATES.keys():
try:
cache = da.from_zarr(filename, val)
if val == 'valid_input_index':
# valid input index array needs to be boolean
cache = cache.astype(np.bool)
# Compute the cache arrays
cache = cache.compute()
except ValueError:
raise IOError
setattr(self.resampler, val, cache)
else:
raise IOError
def save_bil_info(self, cache_dir, **kwargs):
"""Save bilinear resampling info to cache directory."""
if cache_dir:
filename = self._create_cache_filename(cache_dir,
prefix='bil_lut-',
**kwargs)
LOG.info('Saving BIL neighbour info to %s', filename)
zarr_out = xr.Dataset()
for idx_name, coord in BIL_COORDINATES.items():
var = getattr(self.resampler, idx_name)
if isinstance(var, np.ndarray):
var = da.from_array(var, chunks=CHUNK_SIZE)
var = var.rechunk(CHUNK_SIZE)
zarr_out[idx_name] = (coord, var)
zarr_out.to_zarr(filename)
def compute(self, data, fill_value=None, **kwargs):
"""Resample the given data using bilinear interpolation."""
del kwargs
if fill_value is None:
fill_value = data.attrs.get('_FillValue')
target_shape = self.target_geo_def.shape
res = self.resampler.get_sample_from_bil_info(data,
fill_value=fill_value,
output_shape=target_shape)
return update_resampled_coords(data, res, self.target_geo_def)