Package uk.ac.rdg.resc.edal.grid

Class ReferenceableAxisImpl

java.lang.Object

uk.ac.rdg.resc.edal.grid.AbstractReferenceableAxis<T>

uk.ac.rdg.resc.edal.grid.AbstractIrregularAxis<Double>

uk.ac.rdg.resc.edal.grid.ReferenceableAxisImpl

All Implemented Interfaces:

Serializable, DiscreteDomain<Double,Extent<Double>>, Domain<Double>, ReferenceableAxis<Double>

Direct Known Subclasses:

DefinedBoundsAxis, VerticalAxisImpl

public class ReferenceableAxisImpl
extends AbstractIrregularAxis<Double>

Immutable implementation of a ReferenceableAxis, whose values are not necessarily regularly spaced along the axis.

Author:

Guy, Jon

See Also:

Serialized Form

Field Summary

Fields inherited from class uk.ac.rdg.resc.edal.grid.AbstractIrregularAxis

axisValues, reversed

Constructor Summary

Constructors

Constructor	Description
ReferenceableAxisImpl(String name, List<Double> axisValues, boolean isLongitude)	Creates a ReferenceableAxis from the given array of axis values.

Method Summary

Modifier and Type	Method	Description
protected double	difference(Double pos1, Double pos2)	Returns the difference between the supplied values.
boolean	equals(Object obj)
protected Double	extendFirstValue(Double firstVal, Double nextVal)	This should return the lower bound of the first value of the axis, based on the first and second values.
protected Double	extendLastValue(Double lastVal, Double secondLastVal)	This should return the upper bound of the last value of the axis, based on the last two values.
int	findIndexOf(Double position)	Finds the index along this axis that corresponds with the given position.
protected Double	getMidpoint(Double pos1, Double pos2)	Returns the midpoint of the supplied values.
int	hashCode()
boolean	wraps()	Returns true if the values on the axis wrap around (e.g.

Methods inherited from class uk.ac.rdg.resc.edal.grid.AbstractIrregularAxis

checkAscending, getCoordinateBounds, getCoordinateValue, isAscending, size

Methods inherited from class uk.ac.rdg.resc.edal.grid.AbstractReferenceableAxis

contains, getCoordinateExtent, getCoordinateValues, getDomainObjects, getFirstValue, getLastValue, getMaximumValue, getMinimumValue, getName

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ReferenceableAxisImpl

public ReferenceableAxisImpl(String name,
                             List<Double> axisValues,
                             boolean isLongitude)

Creates a ReferenceableAxis from the given array of axis values. The axis values are copied to internal data structures, therefore subsequent modifications to the array of axis values have no effect on this object.

Parameters:

name - The name of the axis

axisValues - List of axis values; must ascend or descend monotonically

isLongitude - True if this is a longitude axis in degrees (hence values of 0 and 360 are equivalent).

Throws:

NullPointerException - if axisValues is null

IllegalArgumentException - if the axis values are not in strictly ascending numerical order, or if the array of axis values is empty

Method Detail

wraps

public boolean wraps()

Description copied from interface: ReferenceableAxis

Returns true if the values on the axis wrap around (e.g. longitude)

findIndexOf

public int findIndexOf(Double position)

Description copied from interface: ReferenceableAxis

Finds the index along this axis that corresponds with the given position. Formally, this returns an index such that getCoordinateBounds(index).contains(position) returns true. Returns -1 if the given position is not associated with any axis index.

If this is a longitude axis, this method will handle the case of longitude values wrapping, therefore values of -180 and +180 are treated as equivalent by this method, irrespective of the values in ReferenceableAxis.getCoordinateValue(int).

Specified by:

findIndexOf in interface ReferenceableAxis<Double>

Overrides:

findIndexOf in class AbstractIrregularAxis<Double>

Returns:

the index of the given coordinate value, or -1 if not found.

extendFirstValue

protected Double extendFirstValue(Double firstVal,
                                  Double nextVal)

Description copied from class: AbstractReferenceableAxis

This should return the lower bound of the first value of the axis, based on the first and second values. This will generally be equivalent to:

firstVal - (nextVal-firstVal)/2

Specified by:

extendFirstValue in class AbstractReferenceableAxis<Double>

Parameters:

firstVal - The first value of the axis

nextVal - The second value of the axis

Returns:

The lower bound of the first axis value

extendLastValue

protected Double extendLastValue(Double lastVal,
                                 Double secondLastVal)

Description copied from class: AbstractReferenceableAxis

This should return the upper bound of the last value of the axis, based on the last two values. This will generally be equivalent to:

lastVal + (lastVal-secondLastVal)/2

Specified by:

extendLastValue in class AbstractReferenceableAxis<Double>

Parameters:

lastVal - The last value of the axis

secondLastVal - The next-to-last value of the axis

Returns:

The upper bound of the the final axis value

difference

protected double difference(Double pos1,
                            Double pos2)

Description copied from class: AbstractIrregularAxis

Returns the difference between the supplied values. This is so that certain methods can be abstracted without worrying about non-trivial difference calculation (e.g. DateTimes)

Specified by:

difference in class AbstractIrregularAxis<Double>

Parameters:

pos1 - the first value

pos2 - the second value

Returns:

the value corresponding to pos1 - pos2

getMidpoint

protected Double getMidpoint(Double pos1,
                             Double pos2)

Description copied from class: AbstractIrregularAxis

Returns the midpoint of the supplied values. This is so that certain methods can be abstracted without worrying about non-trivial midpoint calculation (e.g. DateTimes)

Specified by:

getMidpoint in class AbstractIrregularAxis<Double>

Parameters:

pos1 - the first value

pos2 - the second value

Returns:

the midpoint of the values

hashCode

public int hashCode()

Specified by:

hashCode in interface ReferenceableAxis<Double>

Overrides:

hashCode in class AbstractIrregularAxis<Double>

equals

public boolean equals(Object obj)

Specified by:

equals in interface ReferenceableAxis<Double>

Overrides:

equals in class AbstractIrregularAxis<Double>