exactextract.raster

Classes

RasterSource	Source from which raster data can be read.
GDALRasterSource	RasterSource backed by GDAL
NumPyRasterSource	RasterSource backed by a NumPy array
RasterioRasterSource	RasterSource backed by rasterio
XArrayRasterSource	RasterSource backed by xarray

Module Contents

class exactextract.raster.RasterSource

Source from which raster data can be read.

A RasterSource provides the ability to read subsets of a single band of raster data. Several implementations are included in exactextract:

• GDALRasterSource

• NumPyRasterSource

• RasterioRasterSource

• XArrayRasterSource

class exactextract.raster.GDALRasterSource(ds, band_idx: int = 1, *, name=None)

RasterSource backed by GDAL

Parameters:

• ds – A gdal.Dataset or path from which one can be opened

• band_idx – 1-based numerical index of band to read

• name – source name, to be used in generating field names for results

res()

extent()

nodata_value()

read_window(x0, y0, nx, ny)

srs_wkt()

class exactextract.raster.NumPyRasterSource(mat, xmin=None, ymin=None, xmax=None, ymax=None, *, nodata=None, name=None, srs_wkt=None)

RasterSource backed by a NumPy array

Create a RasterSource that references a NumPy array.

If spatial extent arguments are not provided, the extent will be assumed to be from (0,0) to (nx,ny).

Parameters:

• mat – a two-dimensional NumPy array. Masked arrays are supported.

• xmin – x coordinate of left edge

• ymin – y coordinate of bottom edge

• xmax – x coordinate of right edge

• ymax – y coordinate of top edge

• nodata – Optional value used to indicate missing data.

• name – source name, to be used in generating field names for results

• srs_wkt – WKT string indicating the spatial reference system.

res()

srs_wkt()

extent()

nodata_value()

read_window(x0, y0, nx, ny)

class exactextract.raster.RasterioRasterSource(ds, band_idx=1, *, name=None)

RasterSource backed by rasterio

Parameters:

• ds – A rasterio.DatasetReader or path from which one can be opened

• band_idx – 1-based numerical index of band to read

• name – source name, to be used in generating field names for results

res()

srs_wkt()

extent()

nodata_value()

read_window(x0, y0, nx, ny)

class exactextract.raster.XArrayRasterSource(ds, band_idx=1, *, name=None)

RasterSource backed by xarray

The rio-xarray extension is used to retrieve metadata such as the array extent, resolution, and spatial reference system.

Parameters:

• ds – An xarray DataArray or a path from which one can be read.

• band_idx – 1-based numerical index of band to read

• name – source name, to be used in generating field names for results

srs_wkt()

res()

extent()

nodata_value()

read_window(x0, y0, nx, ny)