This topic describes the ST_MatchGridLevel function. This function determines the highest available grid level based on your terrain elevation data.
Syntax
smallint ST_MatchGridLevel(raster dem);Parameters
Parameter | Description |
dem | The terrain elevation data in the Geodetic Coordinate System (GSC) 2000 coordinate system in EPSG: 4490. |
Description
This function determines the highest available grid level based on the resolution of your terrain elevation data. When you perform path calculations, do not use a grid level that is higher than the highest available grid level. If the coordinate system of the input data is not in EPSG:4490, you can call the ST_Transform function to convert the coordinate system.
Examples
SELECT ST_MatchGridLevel(dem);
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