Distance method

Returns the distance, in meters, between two Geography attributes or variables.

Syntax

GeographyAttOrVar1.Distance(GeographyAttOrVar2)

Where:

GeographyAttOrVar1
   Must be an attribute or variable based on the Geography data type.

GeographyAttOrVar2
   Must be an attribute or variable based on the Geography data type.

Type Returned:
Numeric

Scope

Generators: Apple, Android
Level: Attribute, Variable (Geography data type)

Description

The distance between two points is calculated, but the method accepts geographies and assumes centers or equidistance in the case of calculating it based on GeoLines or GeoPolygon.

Samples

Consider the following Transaction object:

Place
{
  PlaceId*
  PlaceName
  PlaceGeo
}

and the following Structured Data Type (SDT) object:

In this example of 'Places NearBy', the places that are within 1km of the center of the Map are loaded in the &NearPlaces variable (based on the NearPlaces SDT). To do so, the following Procedure object was defined:

Rule:
Parm(&Center);

Variables:
&Center: Geography
&Radius: Numeric(4)
&NearPlaces: NearPlaces (SDT)
&Place: NearPlaces.NearPlacesItem

Source:
&Radius = 1000
For each Place
    where PlaceGeo.Distance(&Center) <= &Radius
     &Place = new()
     &Place.PlaceName = PlaceName
     &Place.PlaceDistance = PlaceGeo.Distance(&Center)/1000  // distance in Kilometers 
     &NearPlaces.Add(&Place)
endfor