/* * Copyright (c) 1998-2018 John Caron and University Corporation for Atmospheric Research/Unidata * See LICENSE for license information. */ package ucar.nc2.ft.point.standard; import ucar.nc2.Attribute; import ucar.nc2.constants.CF; import ucar.nc2.dataset.NetcdfDataset; import ucar.nc2.dataset.CoordinateSystem; import ucar.nc2.dataset.CoordinateAxis; import ucar.nc2.constants.AxisType; import ucar.nc2.Dimension; import java.util.List; /** * CoordinateSystem Evaluation utilities. * * @author caron * @since Dec 16, 2008 */ public class CoordSysEvaluator { /** * search for Axis by Type, assign to TableConfig if found. * search for Lat, Lon, Time, Height. * * @param nt set coordinates short names in this table. * @param ds search in this dataset's "Best" coordinate system. If no CoordSystem, try list of coordinate axes */ public static void findCoords(TableConfig nt, NetcdfDataset ds, Predicate p) { nt.lat = findCoordShortNameByType(ds, AxisType.Lat, p); nt.lon = findCoordShortNameByType(ds, AxisType.Lon, p); nt.time = findCoordShortNameByType(ds, AxisType.Time, p); nt.elev = findCoordShortNameByType(ds, AxisType.Height, p); if (nt.elev == null) nt.elev = findCoordShortNameByType(ds, AxisType.Pressure, p); } /** * search for Axis by Type. * * @param ds search in this dataset's "Best" coordinate system. * @param atype search for this type of CoordinateAxis. takes the first one it finds. * @return the found CoordinateAxis name, or null if none */ public static String findCoordNameByType(NetcdfDataset ds, AxisType atype) { CoordinateAxis coordAxis = findCoordByType(ds, atype); return coordAxis == null ? null : coordAxis.getFullName(); } public static String findCoordShortNameByType(NetcdfDataset ds, AxisType atype) { CoordinateAxis coordAxis = findCoordByType(ds, atype); return coordAxis == null ? null : coordAxis.getShortName(); } public static String findCoordShortNameByType(NetcdfDataset ds, AxisType atype, Predicate p) { CoordinateAxis coordAxis = findCoordByType(ds, atype, p); return coordAxis == null ? null : coordAxis.getShortName(); } /** * Search for Axis by Type. * * @param ds search in this dataset's "Best" coordinate system. * @param atype search for this type of CoordinateAxis. takes the first one it finds. * @return the found CoordinateAxis, or null if none */ public static CoordinateAxis findCoordByType(NetcdfDataset ds, AxisType atype) { return findCoordByType(ds, atype, null); } /** * search for Axis by Type and test against a predicate * * @param ds search in this dataset's "Best" coordinate system. * @param atype search for this type of CoordinateAxis. * @param p match this predicate; may be null * @return the found CoordinateAxis, or null if none */ public static CoordinateAxis findCoordByType(NetcdfDataset ds, AxisType atype, Predicate p) { // try the "best" coordinate system CoordinateSystem use = findBestCoordinateSystem(ds); if (use == null) return null; CoordinateAxis result = findCoordByType(use.getCoordinateAxes(), atype, p); if (result != null) return result; // try all the axes return findCoordByType(ds.getCoordinateAxes(), atype, p); } public static CoordinateAxis findCoordByType(List<CoordinateAxis> axes, AxisType atype, Predicate p) { // first search for matching AxisType and "CF axis" attribute for (CoordinateAxis axis : axes) { if (axis.getAxisType() == atype) { Attribute att = axis.findAttribute(CF.AXIS); if (att != null && att.getStringValue().equals(atype.getCFAxisName()) && (p == null || p.match(axis))) return axis; } } // now match on just the AxisType for (CoordinateAxis axis : axes) { if (axis.getAxisType() == atype && (p == null || p.match(axis))) return axis; } return null; } public interface Predicate { boolean match(CoordinateAxis axis); } /** * search for Dimension used by axis of given by Type. * * @param ds search in this dataset's "Best" coordinate system. * @param atype search for this type of CoordinateAxis. takes the first one it finds. * @return the found CoordinateAxis' first Dimension, or null if none or scalar */ public static Dimension findDimensionByType(NetcdfDataset ds, AxisType atype) { CoordinateAxis axis = findCoordByType(ds, atype); if (axis == null) return null; if (axis.isScalar()) return null; return axis.getDimension(0); } /** * Find the CoordinateSystem with the most number of CoordinateAxes * * @param ds search in this dataset * @return CoordinateSystem or null if none */ private static CoordinateSystem findBestCoordinateSystem(NetcdfDataset ds) { // find coordinate system with highest rank (largest number of axes) CoordinateSystem use = null; for (CoordinateSystem cs : ds.getCoordinateSystems()) { if (use == null) use = cs; else if (cs.getCoordinateAxes().size() > use.getCoordinateAxes().size()) use = cs; } return use; } }