ucar.nc2.dataset

Class CoordinateAxis

java.lang.Object

ucar.nc2.CDMNode

ucar.nc2.Variable

ucar.nc2.dataset.VariableDS

ucar.nc2.dataset.CoordinateAxis

All Implemented Interfaces:

Comparable<VariableSimpleIF>, Iterable<Attribute>, IsMissingEvaluator, AttributeContainer, ucar.nc2.dataset.Enhancements, EnhanceScaleMissingUnsigned, VariableEnhanced, ProxyReader, VariableSimpleIF

Direct Known Subclasses:

CoordinateAxis1D, CoordinateAxis2D

public class CoordinateAxis
extends VariableDS

A Coordinate Axis is a Variable that specifies one of the coordinates of a CoordinateSystem. Mathematically it is a scalar function F from index space to S:

  F:D -> S
  where D is a product set of dimensions (aka index space), and S is the set of reals (R) or Strings.
 

If its element type is char, it is considered a string-valued Coordinate Axis and rank is reduced by one, since the outermost dimension is considered the string length: v(i, j, .., strlen). If its element type is String, it is a string-valued Coordinate Axis. Otherwise it is numeric-valued, and isNumeric() is true.

The one-dimensional case F(i) -> R is the common case which affords important optimizations. In that case, use the subtype CoordinateAxis1D. The factory methods will return either a CoordinateAxis1D if the variable is one-dimensional, a CoordinateAxis2D if its 2D, or a CoordinateAxis for the general case.

A CoordinateAxis is optionally marked as georeferencing with an AxisType. It should have a units string and optionally a description string.

A Structure cannot be a CoordinateAxis, although members of Structures can.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CoordinateAxis.AxisComparator Standard sort on Coordinate Axes
static class	CoordinateAxis.Builder<T extends CoordinateAxis.Builder<T>>

Field Summary

Fields inherited from class ucar.nc2.Variable

defaultCoordsSizeToCache, defaultSizeToCache, permitCaching

Method Summary

Modifier and Type	Method and Description
static CoordinateAxis.Builder<?>	builder() Get Builder for this class that allows subclassing.
CoordinateAxis	copyNoCache() Make a copy, with an independent cache.
boolean	equals(Object oo) Instances which have same content are equal.
static CoordinateAxis.Builder	fromVariableDS(VariableDS.Builder<?> vdsBuilder) Create a coordinate axis from an existing Variable.Builder.
AxisType	getAxisType() Get type of axis
String	getBoundaryRef() The name of this coordinate axis' boundary variable
Calendar	getCalendarFromAttribute()
void	getInfo(Formatter buf) Get a string representation
double	getMaxValue() The largest coordinate value.
double	getMinValue() The smallest coordinate value.
String	getPositive() Get the direction of increasing values, used only for vertical Axes.
String	getUnitsString() Get the Unit String for the Variable.
int	hashCode() Override Object.hashCode() to implement equals.
boolean	isContiguous() If the edges are contiguous or disjoint Caution: many datasets do not explicitly specify this info, this is often a guess; default is true.
boolean	isIndependentCoordinate()
boolean	isInterval() An interval coordinate consists of two numbers, bound1 and bound2.
boolean	isNumeric() Does the axis have numeric values.
CoordinateAxis.Builder<?>	toBuilder() Turn into a mutable Builder.

Methods inherited from class ucar.nc2.dataset.VariableDS

applyScaleOffset, applyScaleOffset, convert, convertMissing, convertMissing, convertUnsigned, convertUnsigned, getCoordinateSystems, getDatasetLocation, getDescription, getEnhanceMode, getFillValue, getMissingDataArray, getMissingValues, getNetcdfFile, getOffset, getOriginalDataType, getOriginalName, getOriginalVariable, getScaledOffsetType, getScaleFactor, getSignedness, getUnsignedConversionType, getValidMax, getValidMin, hasFillValue, hasMissing, hasMissingValue, hasScaleOffset, hasValidData, isFillValue, isInvalidData, isMissing, isMissingValue, lookupEnumString, readToStream, reallyRead, reallyRead, showScaleMissingProxy, toStringDebug

Methods inherited from class ucar.nc2.Variable

attributes, compareTo, createNewCache, findAttribute, findAttributeString, findDimensionIndex, getDataType, getDimension, getDimensions, getDimensionsString, getElementSize, getEnumTypedef, getFileTypeId, getFullName, getNameAndDimensions, getNameAndDimensions, getNameAndDimensions, getParentGroup, getParentStructure, getRanges, getRank, getShape, getShape, getShapeAsSection, getSize, getSizeToCache, getSPobject, hasCachedData, isCaching, isCoordinateVariable, isMemberOfStructure, isMetadata, isScalar, isUnlimited, isVariableLength, read, read, read, read, read, readScalarByte, readScalarDouble, readScalarFloat, readScalarInt, readScalarLong, readScalarShort, readScalarString, reduce, section, section, slice, toString

Methods inherited from class ucar.nc2.CDMNode

getShortName

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface ucar.nc2.dataset.VariableEnhanced

getFullName, getShortName

Methods inherited from interface ucar.nc2.dataset.Enhancements

addCoordinateSystem, removeCoordinateSystem

Methods inherited from interface ucar.nc2.VariableSimpleIF

getShortName

Methods inherited from interface ucar.nc2.AttributeContainer

filter, findAttributeDouble, findAttributeIgnoreCase, findAttributeInteger, getName, hasAttribute, hasAttributeIgnoreCase, isEmpty, iterator

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

builder

public static CoordinateAxis.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"

copyNoCache

public CoordinateAxis copyNoCache()

Make a copy, with an independent cache.

Returns:

copy of this CoordinateAxis

equals

public boolean equals(Object oo)

Instances which have same content are equal.

Overrides:

equals in class Variable

fromVariableDS

public static CoordinateAxis.Builder fromVariableDS(VariableDS.Builder<?> vdsBuilder)

Create a coordinate axis from an existing Variable.Builder.

Parameters:

vdsBuilder - an existing Variable in dataset.

Returns:

CoordinateAxis or one of its subclasses (CoordinateAxis1D, CoordinateAxis2D, or CoordinateAxis1DTime).

getAxisType

public AxisType getAxisType()

Get type of axis

Returns:

type of axis, or null if none.

getBoundaryRef

public String getBoundaryRef()

The name of this coordinate axis' boundary variable

Returns:

the name of this coordinate axis' boundary variable, or null if none.

getCalendarFromAttribute

public Calendar getCalendarFromAttribute()

getInfo

public void getInfo(Formatter buf)

Get a string representation

Parameters:

buf - place info here

getMaxValue

public double getMaxValue()

The largest coordinate value. Only call if isNumeric.

Returns:

the maximum coordinate value

getMinValue

public double getMinValue()

The smallest coordinate value. Only call if isNumeric.

Returns:

the minimum coordinate value

getPositive

public String getPositive()

Get the direction of increasing values, used only for vertical Axes.

Returns:

POSITIVE_UP, POSITIVE_DOWN, or null if unknown.

getUnitsString

public String getUnitsString()

Description copied from class: Variable

Get the Unit String for the Variable. Looks for the CDM.UNITS attribute value

Specified by:

getUnitsString in interface ucar.nc2.dataset.Enhancements

Specified by:

getUnitsString in interface VariableSimpleIF

Overrides:

getUnitsString in class VariableDS

Returns:

unit string, or null if not found.

hashCode

public int hashCode()

Override Object.hashCode() to implement equals.

Overrides:

hashCode in class Variable

isContiguous

public boolean isContiguous()

If the edges are contiguous or disjoint Caution: many datasets do not explicitly specify this info, this is often a guess; default is true.

Returns:

true if the edges are contiguous or false if disjoint. Assumed true unless set otherwise.

isIndependentCoordinate

public boolean isIndependentCoordinate()

isInterval

public boolean isInterval()

An interval coordinate consists of two numbers, bound1 and bound2. The coordinate value must lie between them, but otherwise is somewhat arbitrary. If not interval, then it has one number, the coordinate value.

Returns:

true if its an interval coordinate.

isNumeric

public boolean isNumeric()

Does the axis have numeric values.

Returns:

true if the CoordAxis is numeric, false if its string valued ("nominal").

toBuilder

public CoordinateAxis.Builder<?> toBuilder()

Description copied from class: Variable

Turn into a mutable Builder. Can use toBuilder().build() to copy.

Overrides:

toBuilder in class VariableDS