Package uk.ac.rdg.resc.edal.dataset.plugins

Class VectorPlugin

java.lang.Object

uk.ac.rdg.resc.edal.dataset.plugins.VariablePlugin

uk.ac.rdg.resc.edal.dataset.plugins.VectorPlugin

public class VectorPlugin
extends VariablePlugin

A plugin to generate magnitude and direction fields from x- and y-components, and to group them logically. Direction fields are always generated as headings, in degrees, in WGS84 (i.e. lat-lon), regardless of the CRS of the original data.

Author:

Guy Griffiths

Field Summary

Fields

Modifier and Type	Field	Description
static String	DIR_ROLE
static String	GROUP
static String	MAG_ROLE

Fields inherited from class uk.ac.rdg.resc.edal.dataset.plugins.VariablePlugin

prefixLength, uses

Constructor Summary

Constructors

Constructor	Description
VectorPlugin(String xComponentId, String yComponentId, String commonName, boolean eastNorthComps)	Construct a new VectorPlugin

Method Summary

Modifier and Type	Method	Description
protected VariableMetadata[]	doProcessVariableMetadata(VariableMetadata... metadata)	Subclasses should override this method to modify the VariableMetadata tree, and return any new objects added to it.
protected Number	generateValue(String varSuffix, HorizontalPosition position, Number... sourceValues)	Subclasses should override this method to generate values based on source variable values

Methods inherited from class uk.ac.rdg.resc.edal.dataset.plugins.VariablePlugin

combineIds, generateArray1D, generateArray2D, getFullId, getValue, newVariableMetadataFromDomains, newVariableMetadataFromMetadata, processVariableMetadata, providesVariables, usesVariables

Methods inherited from class java.lang.Object

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

Field Detail

MAG_ROLE

public static final String MAG_ROLE

See Also:

Constant Field Values

DIR_ROLE

public static final String DIR_ROLE

See Also:

Constant Field Values

GROUP

public static final String GROUP

See Also:

Constant Field Values

Constructor Detail

VectorPlugin

public VectorPlugin(String xComponentId,
                    String yComponentId,
                    String commonName,
                    boolean eastNorthComps)

Construct a new VectorPlugin

Parameters:

xComponentId - The ID of the variable representing the x-component

yComponentId - The ID of the variable representing the y-component

commonName - The common part of the standard name of the quantity which the components represent. For example, for components with standard names eastward_sea_water_velocity and northward_sea_water_velocity this would most likely be "sea_water_velocity"

eastNorthComps - true if the components supplied are eastwards/northwards (which may not necessarily be x/y components in the native grid system)

Method Detail

doProcessVariableMetadata

protected VariableMetadata[] doProcessVariableMetadata(VariableMetadata... metadata)
                                                throws EdalException

Description copied from class: VariablePlugin

Subclasses should override this method to modify the VariableMetadata tree, and return any new objects added to it. This allows subclasses to arbitrarily restructure the metadata tree by calling the VariableMetadata.setParent(VariableMetadata, String) methods. Note that the IDs in the newly-created VariableMetadata objects should be generated by calling VariablePlugin.getFullId(String) with the variable's suffix. If the plugin is designed to group several child variables, the first child will be used to automatically estimate the scale range of the parent. This is guaranteed to only be called once.

Specified by:

doProcessVariableMetadata in class VariablePlugin

Parameters:

metadata - An array of VariableMetadata of the source variables in the order they were supplied to the constructor

Returns:

The derived VariableMetadata

Throws:

EdalException - If there is a problem generating new metadata

generateValue

protected Number generateValue(String varSuffix,
                               HorizontalPosition position,
                               Number... sourceValues)

Description copied from class: VariablePlugin

Subclasses should override this method to generate values based on source variable values

Specified by:

generateValue in class VariablePlugin

Parameters:

varSuffix - The suffix ID of the variable to generate VariableMetadata for. This will be one of the provided suffixes in the constructor, but not the actual variable ID (which subclasses do not need to worry about)

position - The HorizontalPosition at which the value is generated. This may affect the returned value

sourceValues - An array of Numbers representing the source values in the order they were supplied to the constructor

Returns:

The derived value