Class SpatialY

Namespace

YndigoBlue.Velocity.Functions

Assembly

YndigoBlue.Velocity.dll

Represents the ST_Y spatial accessor function that returns the Y coordinate of a point geometry.

public class SpatialY : Function, ICheckItem, IDefaultItem, IFilterItem, IElement

Inheritance

object

Function

SpatialY

Implements

ICheckItem

IDefaultItem

IFilterItem

IElement

Remarks

Warning

Spatial functions are not available in the Community Edition of Velocity. They require the Full Edition.

The ST_Y function returns the Y coordinate (latitude or northing) of a point geometry. For non-point geometries, the result is typically null or undefined. The Y coordinate represents the vertical position in the coordinate reference system. For geographic coordinates, Y is latitude. For projected coordinates, Y is the northing value. For Geometry types in planar coordinate systems, this is useful for extracting coordinates, coordinate transformations, or point analysis. OGC-compliant.

Return Type: Double (Y coordinate value).

Point Geometry	ST_Y Result
POINT(200 100)	100
POINT(-98.5 38.2)	38.2 (latitude)
LineString, Polygon	NULL

Examples

Retrieve the Y (latitude) coordinate of each point location in a stores table:

var schema = manager.LoadSchema("retail");
var stores = schema["stores"];

var query = new Query()
    .Select([ stores["id"], stores["name"], new Expression("latitude", new SpatialY(stores["location"])) ])
    .From(stores);

var results = manager.Retrieve(query);

Constructors

SpatialY(Geometry)

Initializes a new instance of ST_Y with a point geometry literal.

SpatialY(Column)

Initializes a new instance of ST_Y with a point geometry column.

SpatialY(Function)

Initializes a new instance of ST_Y for a function result.

SpatialY(Geography)

Initializes a new instance of ST_Y with a point geography literal.