Package ucar.nc2.dataset

Class CoordinateAxis1D

  • All Implemented Interfaces:
    Comparable<VariableSimpleIF>, Iterable<Attribute>, IsMissingEvaluator, AttributeContainer, ucar.nc2.dataset.Enhancements, ucar.nc2.dataset.EnhanceScaleMissingUnsigned, VariableEnhanced, ProxyReader, VariableSimpleIF
    Direct Known Subclasses:
    CoordinateAxis1DTime
    public class CoordinateAxis1D
extends CoordinateAxis
    A 1-dimensional Coordinate Axis. Its values must be monotonic.

    If this is char valued, it will have rank 2, otherwise it will have rank 1.

    If string or char valued, only getCoordName() can be called.

    If the coordinates are regularly spaced, isRegular() is true, and the values are equal to getStart() + i * getIncrement().

    This will also set "cell bounds" for this axis. By default, the cell bounds are midway between the coordinates values, and are therefore contiguous, and can be accessed though getCoordEdge(i). The only way the bounds can be set is if the coordinate variable has an attribute "bounds" that points to another variable bounds(ncoords,2). These contain the cell bounds, and must be ascending or descending as the coordinate values are. In this case isContiguous() is true when bounds1(i+1) == bounds2(i) for all i.

    See Also:
    CoordinateAxis.fromVariableDS(ucar.nc2.dataset.VariableDS.Builder<?>)

    • Method Detail

      • getCoordName

        public String getCoordName​(int index)
        The "name" of the ith coordinate. If nominal, this is all there is to a coordinate. If numeric, this will return a String representation of the coordinate.
        Parameters:
        index - which one ?
        Returns:
        the ith coordinate value as a String

      • getCoordValue

        public double getCoordValue​(int index)
        Get the ith coordinate value. This is the value of the coordinate axis at which the data value is associated. These must be strictly monotonic.
        Parameters:
        index - which coordinate. Between 0 and getNumElements()-1 inclusive.
        Returns:
        coordinate value.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • getMinValue

        public double getMinValue()
        Description copied from class: CoordinateAxis
        The smallest coordinate value. Only call if isNumeric.
        Overrides:
        getMinValue in class CoordinateAxis
        Returns:
        the minimum coordinate value

      • getMaxValue

        public double getMaxValue()
        Description copied from class: CoordinateAxis
        The largest coordinate value. Only call if isNumeric.
        Overrides:
        getMaxValue in class CoordinateAxis
        Returns:
        the maximum coordinate value

      • getMinEdgeValue

        public double getMinEdgeValue()

      • getMaxEdgeValue

        public double getMaxEdgeValue()

      • getCoordEdge

        public double getCoordEdge​(int index)
        Get the ith coordinate edge. Exact only if isContiguous() is true, otherwise use getBound1() and getBound2(). This is the value where the underlying grid element switches from "belonging to" coordinate value i-1 to "belonging to" coordinate value i. In some grids, this may not be well defined, and so should be considered an approximation or a visualization hint. 

          Coordinate edges must be strictly monotonic:
    coordEdge(0) < coordValue(0) < coordEdge(1) < coordValue(1) ...
    ... coordEdge(i) < coordValue(i) < coordEdge(i+1) < coordValue(i+1) ...
    ... coordEdge(n-1) < coordValue(n-1) < coordEdge(n)
        Parameters:
        index - which coordinate. Between 0 and getNumElements() inclusive.
        Returns:
        coordinate edge.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • getCoordValues

        public double[] getCoordValues()
        Get the coordinate values as a double array.
        Returns:
        coordinate value.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • getCoordEdges

        public double[] getCoordEdges()
        Get the coordinate edges as a double array. Exact only if isContiguous() is true, otherwise use getBound1() and getBound2().
        Returns:
        coordinate edges.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • isContiguous

        public boolean isContiguous()
        Description copied from class: CoordinateAxis
        If the edges are contiguous or disjoint Caution: many datasets do not explicitly specify this info, this is often a guess; default is true.
        Overrides:
        isContiguous in class CoordinateAxis
        Returns:
        true if the edges are contiguous or false if disjoint. Assumed true unless set otherwise.

      • isInterval

        public boolean isInterval()
        If this coordinate has interval values. If so, then one should use getBound1, getBound2, and not getCoordEdges()
        Overrides:
        isInterval in class CoordinateAxis
        Returns:
        true if coordinate has interval values

      • getBound1

        public double[] getBound1()
        Get the coordinate bound1 as a double array. bound1[i] # coordValue[i] # bound2[i], where # is < if increasing (bound1[i] < bound1[i+1]) else < if decreasing.
        Returns:
        coordinate bound1.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • getBound2

        public double[] getBound2()
        Get the coordinate bound1 as a double array. bound1[i] # coordValue[i] # bound2[i], where # is < if increasing (bound1[i] < bound1[i+1]) else < if decreasing.
        Returns:
        coordinate bound2.
        Throws:
        UnsupportedOperationException - if !isNumeric()

      • getCoordBounds

        public double[] getCoordBounds​(int i)
        Get the coordinate bounds for the ith coordinate. Can use this for isContiguous() true or false.
        Parameters:
        i - coordinate index
        Returns:
        double[2] edges for ith coordinate

      • getCoordBoundsMidpoint

        public double getCoordBoundsMidpoint​(int i)

      • findCoordElement

        public int findCoordElement​(double coordVal)
        Given a coordinate value, find what grid element contains it. This means that 
         edge[i] <= value < edge[i+1] (if values are ascending)
 edge[i] > value >= edge[i+1] (if values are descending)
        Parameters:
        coordVal - position in this coordinate system
        Returns:
        index of grid point containing it, or -1 if outside grid area

      • findCoordElementBounded

        public int findCoordElementBounded​(double coordVal)
        Given a coordinate position, find what grid element contains it, or is closest to it.
        Parameters:
        coordVal - position in this coordinate system
        Returns:
        index of grid point containing it, or best estimate of closest grid interval.

      • getStart

        public double getStart()
        Get starting value if isRegular()
        Returns:
        starting value if isRegular()

      • getIncrement

        public double getIncrement()
        Get increment value if isRegular()
        Returns:
        increment value if isRegular()

      • isRegular

        public boolean isRegular()
        If true, then value(i) = getStart() + i * getIncrement().
        Returns:
        if evenly spaced.

      • builder

        public static CoordinateAxis1D.Builder<?> builder()
        Get Builder for this class that allows subclassing.
        See Also:
        "https://community.oracle.com/blogs/emcmanus/2010/10/24/using-builder-pattern-subclasses"