A thin wrapper around NetCDF-Java for reading sub-schemas of variables into Java objects.
Take for example a simple NetCDF file with the following dimensions and variables:
Dimensions
- x(length=10)
- y(length=10)
- z(length=10)
Variables
- latitude(type=double, dimensions=[x]) // each step along the x dimension corresponds to new latitude
- longitude(type=double, dimensions=[y]) // each step along the y dimension corresponds to new longitude
- level(type=int, dimensions=[z]) // each step along the z dimension corresponds to new step higher in the atmosphere
- temperature(type=float, dimensions=[x,y,z]) // at each (x,y,z) coordinate we have a temperature observation/prediction
- pressure(type=float, dimensions=[x,y,z]) // at each (x,y,z) coordinate we have a pressure observation/predictionThis library allows clients to quickly read these variables and organize them into simple objects for more natural use in an application:
record Measurement(double latitude, double longitude, int level, float temperature,
float pressure) { /* Plus a builder */
}
var binding = SchemaBinding.<Measurement.Builder>builder()
.doubleDimensionVariable("x", "latitude", Measurement.Builder::latitude)
.doubleDimensionVariable("y", "longitude", Measurement.Builder::longitude)
.intDimensionVariable("z", "level", Measurement.Builder::level)
.floatCoordinateVariable("temperature", Measurement.Builder::temperature)
.floatCoordinateVariable("pressure", Measurement.Builder::pressure)
.build();
// To read alternate file types add the appropriate runtime dependency, e.g. runtimeOnly(edu.ucar:grib) for grib2
NetcdfFile file = NetcdfFiles.open("/path/to/some/file.nc");
Stream<Measurement> measurements = NetcdfRecordReader.schemaBound(binding).read(file)
.map(Measurement.Builder::build);- To resolve the transitive ucar dependencies you'll need to configure their repository as a source (see
the
lib/build.gradle.ktsof this project) - This repo is published to maven central as
io.github.stellarsunset:netcdf, see releases for versions - The additional Java artifacts for reading alternate file types can be found on the ucar site
- Add support for dimension range restrictions
- Coordinate transform extractors (e.g. lambertian)