nd.warp package¶
-
class
nd.warp.
Alignment
(target=None, crs=None, extent=None)[source]¶ Bases:
nd.algorithm.Algorithm
Align a list of datasets to the same coordinate grid.
- Parameters
target (xarray.Dataset, optional) – Align the datasets with respect to the target dataset.
crs (str or dict, optional) – The coordinate reference system as proj-string or dictionary. By default, use the CRS of the datasets.
extent (tuple, optional) – The bounding box of the output dataset. By default, use the common extent of all datasets.
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apply
(datasets, path, *, njobs=1)[source]¶ Resample datasets to common extent and resolution.
- Parameters
datasets (str, list of str, list of xarray.Dataset) – The input datasets. Can be either a glob expression, a list of filenames, or a list of opened datasets.
path (str) – The output path to store the aligned datasets.
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
-
class
nd.warp.
Coregistration
(reference=0, upsampling=10)[source]¶ Bases:
nd.algorithm.Algorithm
Coregister a time series (stack) of images to a master image.
At the moment only supports coregistration by translation.
- Parameters
reference (int, optional) – The time index to use as reference for coregistration (default: 0).
upsampling (int, optional) – The upsampling factor for shift estimation (default: 10).
-
class
nd.warp.
Reprojection
(target=None, src_crs=None, dst_crs=None, crs=None, extent=None, res=None, width=None, height=None, transform=None, **kwargs)[source]¶ Bases:
nd.algorithm.Algorithm
Reprojection of the dataset to the given coordinate reference system (CRS) and extent.
- Parameters
target (xarray.Dataset or xarray.DataArray, optional) – A reference to which a dataset will be aligned.
src_crs (dict or str, optional) – The coordinate system of the input data (default: infer from data).
dst_crs (dict or str, optional) – The output coordinate reference system as dictionary or proj-string
crs (dict or str, optional) – Alias for dst_crs for backwards compatiblity.
extent (tuple, optional) – The output extent. By default this is inferred from the input data.
res (tuple, optional) – The output resolution. By default this is inferred from the input data.
width (tuple, optional) – The output width. By default this is inferred from the input data.
height (tuple, optional) – The output height. By default this is inferred from the input data.
transform (tuple, optional) – The output coordinate transform. By default this is inferred from the input data.
**kwargs (dict, optional) – Extra keyword arguments for
rasterio.warp.reproject
.
-
apply
(ds, *, njobs=1)[source]¶ Apply the projection to a dataset.
- Parameters
ds (xarray.Dataset) – The input dataset.
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
- Returns
The reprojected dataset.
- Return type
xarray.Dataset
-
class
nd.warp.
Resample
(res=None, width=None, height=None, **kwargs)[source]¶ Bases:
nd.algorithm.Algorithm
Resample a dataset to the specified resolution or width and height.
- Parameters
res (float or tuple, optional) – The desired resolution in the dataset coordinates.
width (int, optional) – The desired output width. Ignored if the resolution is specified. If only the height is given, the width is calculated automatically.
height (int, optional) – The desired output height. Ignored if the resolution is specified. If only the width is given, the height is calculated automatically.
**kwargs (dict, optional) – Extra keyword arguments for
rasterio.warp.reproject
.
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apply
(ds, *, njobs=1)[source]¶ Resample the dataset.
- Parameters
ds (xarray.Dataset or xarray.DataArray) – The input dataset
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
- Returns
The resampled dataset.
- Return type
xarray.Dataset or xarray.DataArray
-
nd.warp.
align
(datasets, path, target=None, crs=None, extent=None, *, njobs=1)[source]¶ Wrapper for
nd.warp.Alignment
.Align a list of datasets to the same coordinate grid.
- Parameters
datasets (str, list of str, list of xarray.Dataset) – The input datasets. Can be either a glob expression, a list of filenames, or a list of opened datasets.
path (str) – The output path to store the aligned datasets.
target (xarray.Dataset, optional) – Align the datasets with respect to the target dataset.
crs (str or dict, optional) – The coordinate reference system as proj-string or dictionary. By default, use the CRS of the datasets.
extent (tuple, optional) – The bounding box of the output dataset. By default, use the common extent of all datasets.
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
-
nd.warp.
coregister
(ds, reference=0, upsampling=10)[source]¶ Wrapper for
nd.warp.Coregistration
.Coregister a time series (stack) of images to a master image.
At the moment only supports coregistration by translation.
- Parameters
ds (xarray.Dataset) – The input dataset.
reference (int, optional) – The time index to use as reference for coregistration (default: 0).
upsampling (int, optional) – The upsampling factor for shift estimation (default: 10).
- Returns
The coregistered dataset.
- Return type
xarray.Dataset
-
nd.warp.
get_bounds
(ds)[source]¶ Extract the bounding box in projection coordinates.
- Parameters
ds (xarray.Dataset) – The input dataset
- Returns
The bounding box in projection coordinates (left, bottom, right, top).
- Return type
tuple
-
nd.warp.
get_common_bounds
(datasets)[source]¶ Calculate the common bounding box of the input datasets.
- Parameters
datasets (list of xarray.Dataset) – The input datasets.
- Returns
The common bounding box (left, bottom, right, top) in projected coordinates.
- Return type
tuple
-
nd.warp.
get_common_extent
(datasets)[source]¶ Calculate the smallest extent that contains all of the input datasets.
- Parameters
datasets (list of xarray.Dataset) – The input datasets.
- Returns
The common extent (left, bottom, right, top) in latitude and longitude coordinates.
- Return type
tuple
-
nd.warp.
get_common_resolution
(datasets, mode='min')[source]¶ Determine the common resolution of a list of datasets.
- Parameters
datasets (list of xarray.Dataset) – The input datasets.
mode (str {'min', 'max', 'mean'}) –
How to determine the common resolution if the individual resolutions differ.
min
: Return the smallest (best) resolution.max
: Return the largest (worst) resolution.mean
: Return the average resolution.
- Returns
Returns the common resolution as (x, y).
- Return type
tuple
-
nd.warp.
get_crs
(ds, format='crs')[source]¶ Extract the Coordinate Reference System from a dataset.
- Parameters
ds (xarray.Dataset) – The input dataset
format (str {'crs', 'proj', 'dict', 'wkt'}) –
The format in which to return the CRS.
’proj’: A proj-string, e.g.
+init=epsg:4326
’dict’: e.g.
{'init': 'EPSG:4326'}
’wkt’: e.g.
GEOGCS["WGS 84", ...]
- Returns
The CRS.
- Return type
CRS, str, or dict
-
nd.warp.
get_extent
(ds)[source]¶ Extract the extent (bounding box) from the dataset.
- Parameters
ds (xarray.Dataset) – The input dataset
- Returns
The extent (left, bottom, right, top) in latitude and longitude coordinates.
- Return type
tuple
-
nd.warp.
get_geometry
(ds, crs={'init': 'epsg:4326'})[source]¶ Get the shapely geometry of the dataset bounding box in any coordinate system (EPSG:4326 by default).
- Parameters
ds (xr.Dataset or xr.DataArray) – The dataset whose geometry to return.
crs (dict, optional) – The desired CRS as keywords arguments to be passed to
pyproj.Proj
.
- Returns
The bounds of the dataset in the desired coordinate system.
- Return type
shapely.geometry.Polygon
-
nd.warp.
get_resolution
(ds)[source]¶ Extract the resolution of the dataset in projection coordinates.
- Parameters
ds (xarray.Dataset) – The input dataset
- Returns
The raster resolution as (x, y)
- Return type
tuple
-
nd.warp.
get_transform
(ds)[source]¶ Extract the geographic transform from a dataset.
- Parameters
ds (xarray.Dataset) – The input dataset
- Returns
The affine transform
- Return type
affine.Affine
-
nd.warp.
reproject
(ds, target=None, src_crs=None, dst_crs=None, crs=None, extent=None, res=None, width=None, height=None, transform=None, *, njobs=1, **kwargs)[source]¶ Wrapper for
nd.warp.Reprojection
.Reprojection of the dataset to the given coordinate reference system (CRS) and extent.
- Parameters
ds (xarray.Dataset) – The input dataset.
target (xarray.Dataset or xarray.DataArray, optional) – A reference to which a dataset will be aligned.
src_crs (dict or str, optional) – The coordinate system of the input data (default: infer from data).
dst_crs (dict or str, optional) – The output coordinate reference system as dictionary or proj-string
crs (dict or str, optional) – Alias for dst_crs for backwards compatiblity.
extent (tuple, optional) – The output extent. By default this is inferred from the input data.
res (tuple, optional) – The output resolution. By default this is inferred from the input data.
width (tuple, optional) – The output width. By default this is inferred from the input data.
height (tuple, optional) – The output height. By default this is inferred from the input data.
transform (tuple, optional) – The output coordinate transform. By default this is inferred from the input data.
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
**kwargs (dict, optional) – Extra keyword arguments for
rasterio.warp.reproject
.
- Returns
The reprojected dataset.
- Return type
xarray.Dataset
-
nd.warp.
resample
(ds, res=None, width=None, height=None, *, njobs=1, **kwargs)[source]¶ Wrapper for
nd.warp.Resample
.Resample a dataset to the specified resolution or width and height.
- Parameters
ds (xarray.Dataset or xarray.DataArray) – The input dataset
res (float or tuple, optional) – The desired resolution in the dataset coordinates.
width (int, optional) – The desired output width. Ignored if the resolution is specified. If only the height is given, the width is calculated automatically.
height (int, optional) – The desired output height. Ignored if the resolution is specified. If only the width is given, the height is calculated automatically.
njobs (int, optional) – Number of jobs to run in parallel. Setting njobs to -1 uses the number of available cores. Disable parallelism by setting njobs to 1 (default).
**kwargs (dict, optional) – Extra keyword arguments for
rasterio.warp.reproject
.
- Returns
The resampled dataset.
- Return type
xarray.Dataset or xarray.DataArray