Time Dependent Locations

In the case that FEWS is used as a forecasting system the locations dont need to be time dependent in the majority of the cases. The time span of a forecating system is usually several weeks.

For such a short time span the configuration of the locations can be static and if something changes in one of the forecasting locations this can be changed in the FEWS system without keeping track of the situation was before the change.

However when FEWS is used for a Water Information System (WIS) it is important that FEWS also has knowledge of how the location configuration was in the past. In a WIS the time span is much larger and can be as large as 10 or 20 years.

To make it possible to reproduce the time series generated in the past it is necessary that FEWS still has knowledge about how the location configuration was in the past.

The chapter will describe how it is possible to configure time dependent locations. It is also very important to note that only the functionality which is described in this chapter can be considered time depedent.

Configuration of time dependent locations

What exactly is a time dependent location? A time dependent location has a start- and a endtime. In addition the attributes, but also the related locations of the location can vary in time.

A set of time depedent locations can be configured int the LocationSets.xml file. 

<locationSet id="example">
	<csvFile>
	<file>myLocationFile</file>
	<geoDatum>Rijks Driehoekstelsel</geoDatum>
	<id>%ID%</id>
	<name>%NAME%</name>
	<description>Example of time dependent locations</description>
	<visibilityStartTime>%START%</visibilityStartTime>
	<visibilityEndTime>%EIND%</visibilityEndTime>-->
	<x>%X%</x>
	<y>%Y%</y>
	<relation id="relation">
		<relatedLocationId>%REL%</relatedLocationId>
	</relation>
	<attribute id="PARAMETERS">
		<text>%PARAMETERS%</text>
	</attribute>
	<attributeFile>
	<csvFile>attribute.csv</csvFile>
	<id>%ID%</id>
	<timeZoneOffset>+00:00</timeZoneOffset>
	<attribute id="Q">
	<number>%Q%</number>
	</attribute>
	</attributeFile>
	</csvFile>
</locationSet>