Rasters
Rasters.jl defines common types and methods for reading, writing and manipulating rasterized spatial data.
These currently include raster arrays like GeoTIFF and NetCDF, R grd files, multi-layered stacks, and multi-file series of arrays and stacks.
A RasterStack of EarthEnv HabitatHeterogeneity layers, trimmed to Australia and plotted with Plots.jl
Lazyness
- Data is loaded lazily wherever possible using
DiskArrays.jl. Indexing a
RasterStack
by name is always lazy, whileview
of aRaster
is lazy andgetindex
will load to memory.read
can be used on any object to ensure that all data is loaded to memory. - Broadcast over disk-based objects is lazy - it will only run when the array is indexed. Always prefer broadcasts to explicit loops - these can be very slow with disk-based data.
Data-source abstraction
Rasters provides a standardised interface that allows many source data types to be used with identical syntax.
- Scripts and packages building on Rasters.jl can treat
AbstractRaster
,AbstractRasterStack
, andAbstrackRasterSeries
as black boxes.- The data could hold GeoTiff or NetCDF files,
Array
s in memory orCuArray
s on the GPU - they will all behave in the same way. RasterStack
can be backed by a Netcdf or HDF5 file, or aNamedTuple
ofRaster
holding.tif
files, or allRaster
in memory.- Users do not have to deal with the specifics of spatial file types.
- The data could hold GeoTiff or NetCDF files,
Projected
lookups with Cylindrical projections can by indexed using other Cylindrical projections by setting themappedcrs
keyword on construction. You don't need to know the underlying projection, the conversion is handled automatically. This means lat/lonEPSG(4326)
can be used seamlessly if you need that.- Regions and points selected with
Between
andContains
select the right point or whole interval no matter the order of the index or it's position in the cell.
Named dimensions and index lookups
Rasters.jl extends
DimensionalData.jl so that
spatial data can be indexed using named dimensions like X
, Y
and Ti
(time)
and e.g. spatial coordinates.
Dimensions can also be used in most Base
and Statistics
methods like mean
and reduce
where dims
arguments are required. Much of the behaviour is
covered in the DimensionalData
docs.
See the docs for more details and examples for Rasters.jl.