Elevation - Revision history

Judy: /* Usage */

2015-12-14T15:34:48Z

‎Usage

Judy: /* Usage */

2014-11-25T15:57:50Z

‎Usage

Judy: /* Usage */

2014-11-25T15:56:52Z

‎Usage

Judy: /* ELEVATION */

2013-03-28T11:34:24Z

‎ELEVATION

Judy: /* Usage */

2013-03-28T10:51:45Z

‎Usage

Judy: /* Usage */

2013-03-28T10:51:10Z

‎Usage

Bart: /* Usage */

2008-05-19T14:38:23Z

‎Usage

Bart: /* ELEVATION */

2008-05-19T14:38:05Z

‎ELEVATION

Bart: /* ELEVATION */

2008-05-16T13:40:22Z

‎ELEVATION

Bart: /* Usage */

2008-05-16T13:39:40Z

‎Usage

@@ Line 8: / Line 8: @@
 == Usage ==
-   select elevation.srtm_getvalue(pointfromtext('POINT(<longitude> <latitude>)',4326))
+   select elevation.srtm_getvalue(ST_pointfromtext('POINT(<longitude> <latitude>)',4326))
 i.e.
-   select elevation.srtm_getvalue(pointfromtext('POINT(6.99666 49.504)',4326))
+   select elevation.srtm_getvalue(ST_pointfromtext('POINT(6.99666 49.504)',4326))
    or
-   select elevation.srtm_getvalue (pointfromtext('POINT(86.93333 27.983333)',4326));
+   select elevation.srtm_getvalue (ST_pointfromtext('POINT(86.93333 27.983333)',4326));
 To use only high- or low resolution the following can be used resp.
-   select elevation.srtm3_getvalue(pointfromtext('POINT(6.99666 49.504)',4326)) -- high res
+   select elevation.srtm3_getvalue(ST_pointfromtext('POINT(6.99666 49.504)',4326)) -- high res
-   select elevation.srtm30_getvalue(pointfromtext('POINT(6.99666 49.504)',4326)) -- low res
+   select elevation.srtm30_getvalue(ST_pointfromtext('POINT(6.99666 49.504)',4326)) -- low res

@@ Line 29: / Line 29: @@
    SELECT device_info_serial, date_time, latitude, longitude, elevation.srtm_getvalue("location") AS DEM
-   FROM gps.uva_tracking_data
+   FROM gps.ee_tracking_speed_limited
    WHERE device_info_serial = <device_info_serial>
@@ Line 36: / Line 36: @@
    SELECT device_info_serial, date_time, latitude, longitude, elevation.srtm_getvalue("location") AS DEM
-   FROM gps.uva_tracking_data
+   FROM gps.ee_tracking_speed_limited
    WHERE device_info_serial = 60

← Older revision		Revision as of 15:56, 25 November 2014
Line 51:		Line 51:

	All tiles have been redistributed into rasters of 60 * 60		All tiles have been redistributed into rasters of 60 * 60
		+
		+	== Usage within R ==
		+
		+	If a user would like to access the elevation data for a series of locations, than the location field can be used, which is a composite, text field including longitude and latitude of each GPS point, do not run this query for very large datasets without testing first on a subset of data. This function can also be used from with R but needs a slightly different notation (namely removing quotations around the field location). In the following query elevation.srtm_getvalue(location) AS DEM returns the surface elevation (m) and altitude - elevation.srtm_getvalue(location) AS ALT_AGL returns the GPS altitude above the surface (m) for one specific bird and within a range of dates:
		+
		+	SELECT device_info_serial, date_time, latitude, longitude, elevation.srtm_getvalue(location) AS DEM, altitude - elevation.srtm_getvalue(location) AS ALT_AGL
		+	FROM gps.ee_tracking_speed_limited
		+	WHERE device_info_serial = <device_info_serial> and date_time >= 'yyyy-mm-dd hh:mm:ss' and date_time <= 'yyyy-mm-dd hh:mm:ss'
		+
		+	i.e.
		+	SELECT device_info_serial, date_time, latitude, longitude, elevation.srtm_getvalue(location) AS DEM, altitude - elevation.srtm_getvalue(location) AS ALT_AGL
		+	FROM gps.ee_tracking_speed_limited
		+	WHERE device_info_serial = 6015 and date_time >= '2014-06-27 00:00:00' and date_time <= '2014-06-28 00:00:00'

	== Links ==		== Links ==

← Older revision		Revision as of 11:34, 28 March 2013
Line 1:		Line 1:
	= ELEVATION =		= ELEVATION =

−	~~Get~~ the ~~elevation~~ for ~~specific point~~ on ~~Earth~~. There is a high resolution (srtm3) and low resolution (srtm30) dataset available. The srtm_getvalue will first try the high-resolution dataset for the specific location and the low-resolution if the first did not give a result.	+	The database includes a global digital elevation model (DEM) developed from the Shutter Radar Topography Mission(SRTM) data (for more information on the data source, see [[links]]). There is a high resolution (srtm3) and low resolution (srtm30) dataset available in the database. The function elevation.srtm_getvalue extracts the land surface elevation (m) stored in the database for a given set of coordinates (longitude and latitude) which is parsed as text in the function. The elevation.srtm_getvalue function will first try the high-resolution dataset for the specific location and the low-resolution if the first did not give a result.
		+
		+	The function can be used in different ways, shown below.

@@ Line 5: / Line 5: @@
 == Usage ==
    select elevation.srtm_getvalue(pointfromtext('POINT(<longitude> <latitude>)',4326))
@@ Line 32: / Line 30: @@
    WHERE device_info_serial = <device_info_serial>
- i.e.
+i.e.

@@ Line 1: / Line 1: @@
 = ELEVATION =
-Get the elevation for specific point on Earth.
+Get the elevation for specific point on Earth.  There is a high resolution (srtm3) and low resolution (srtm30) dataset available. The srtm_getvalue will first try the high-resolution dataset for the specific location and the low-resolution if the first did not give a result.
 == Usage ==
@@ Line 17: / Line 18: @@
-When srtm3 does not give an elevation, srtm30 is used
+To use only high- or low resolution the following can be used resp.
 On borders between cells the south and/or east  cell is selected, also between tiles!

← Older revision		Revision as of 13:40, 16 May 2008
Line 1:		Line 1:
	= ELEVATION =		= ELEVATION =
		+
		+	Get the elevation for specific point on Earth.

	== Usage ==		== Usage ==