Options - 23.1

Spectrum Dataflow Designer Guide

Version
23.1
Language
English
Product name
Spectrum Technology Platform
Title
Spectrum Dataflow Designer Guide
Copyright
2024
First publish date
2007
Last updated
2024-10-11
Published on
2024-10-11T22:55:47.128293
Table 1. Legacy Find Nearest Options

Option

Description

Named table

The name of the named table that contains the points of interest you want to find. For example, if you want to find the nearest grocery store, the spatial data would contain the coordinates of all grocery stores.

Routing database

The name of the database that contains the routing data to use to determine the shortest or fastest route. Use the database name specified in the Management Console's Database Resources tool. For more information, see Creating a Routing Database Resource.

Search criteria

Specifies how you want to identify the nearest point of interest. One of the following:

Fastest
Find the point of interest that takes the shortest amount of time to drive to.
Proximity
Find the point of interest that is the closest linear distance. Default.
Shortest
Find the point of interest that is the shortest driving distance.

In some cases the point of interest that is the shortest driving distance may be different from the point that has the shortest travel time. This could occur if, for example, there is a highway to the further point but only a surface road to the closer point. The highway could result in faster travel speed and therefore a shorter travel time despite the longer distance.

Likewise, the point of interest that is the shortest linear distance may not be the same as the point within the shortest driving distance. In the following illustration, note that the point that the closest linear distance is different from the point that is the closest travel distance since there is a lake that must be driven around in order to reach the point that is the closest linear distance.

Note: Selecting "Fastest" or "Shortest" in this field will result in an output field called Time, which reports the time it takes to get from the input point to the point of interest.

Coordinate system

The coordinate system of the input coordinates.

To change the default coordinate system, clear the default value then start typing the name of a coordinate system or an EPSG code to see a drop-down list of systems that begin with or contain those characters (the list appears after you have entered three alphanumeric characters). You can also click the browse button to open the Select Coordinate System dialog and select one from the list. Regardless of which coordinate system you select, the descriptive name will appear in the field and the respective EPSG code is saved for the stage.

For more information on EPSG codes, see www.spatialreference.org. To retrieve a list of supported codespaces for EPSG, you can submit the SOAP request List Supported CoordSys by Code Space from the Geometry Service Demo page at http://<server>:<port>/Spatial/GeometryService/DemoPage.html.

Coordinate format

Specifies the format of latitude/longitude coordinates in the input.

Note: Use this option only if you specify a Latitude/Longitude coordinate system. If the coordinate system is not a Latitude/Longitude coordinate system, set the coordinate format to Decimal.

One of the following:

Decimal
(90.000000, 180.000000). Default.
Decimal Assumed
(90000000, 180000000).
Degrees Minutes Seconds
(90 00 00N, 180 00 00W)
Pre-Zero
(090000000N, 180000000W)
Pre-Zero Decimal
(090.000000N, 180.000000W)

Distance units

Specifies how distance values are returned. One of the following:

Feet
Return distance in feet.
Kilometers
Return distance in kilometers.
Meters
Return distance in meters.
Miles
Return distance in miles. Default.
Yards
Return distance in yards.

Maximum distance

The default radius of the search area in which to look for nearby points of interest. You can override this default value on a record-by-record basis by specifying the MaxDistance input field. Specify the radius in the units selected in the Distance units option. For example, to look for points of interest within a 10 mile radius, specify "10" in this field and select "Miles" in the Distance units option. The default is 0.

Time units

Specifies how time values are returned. One of the following:

Hours
Return distance in hours.
Minutes
Return distance in minutes. Default.
Seconds
Return distance in seconds.

Maximum candidates

Specifies the maximum number of points of interest to return. If you specify "1" only the nearest point of interest is returned. If you specify "2" the two nearest points of interest are returned, and so forth. The default is 1.

Return point-of-interest geometry

Specifies whether to return the geometry of the point of interest. The point-of-interest geometry could be a point (such as a store location), line (such as a road segment), or polygon (such as a national park). The type of geometry returned depends on the data contained in the named table.