15 votes

Seeking alternative to Google Maps Elevation API

I've been working on opentopodata.org as a free, open alternative to the Google Maps Elevation API. Request URLs look like this: https://api.opentopodata.org/v1/eudem25m?locations=51.875127,-3....
bckygldstn's user avatar
15 votes
Accepted

Obtaining elevation data for points using QGIS

Basic steps to get elevation data in GPS points: Obtain an elevation raster for your area of interest. You'll need a DEM (Digital Elevation Model) raster, which is a raster of pure elevation data ...
csk's user avatar
  • 24.7k
12 votes
Accepted

Querying Elevation Data in Postgis

Your elevation points are definitely regularly aligned and hence there is no need to bother about nearest neighbors. The value of the pixel in which your point fall into is always the value of the ...
Pierre Racine's user avatar
10 votes
Accepted

Converting sign for a 32-bit GeoTIFF with an open source tool?

I don't know if this is the easiest way, but one way would be to use gdal_calc.py from GDAL: gdal_calc.py -A positive_values.tif --outfile=negative_values.tif --calc="A*(-1.0)"
Rich Signell's user avatar
  • 2,262
10 votes
Accepted

Elevation from TIFF file

Save the Excel file as CSV In GIS, add the CSV file to QGIS using "Layer > Add Layer > Add Delimited Text Layer" Use "Sample raster values" from "Processing Toolbox (...
Kadir Şahbaz's user avatar
9 votes
Accepted

Getting elevation at particular coordinate (lat/lon) programmatically (but offline)?

You can use the rasterio library: import rasterio coords = ((147.363,-36.419), (147.361,-36.430)) elevation = 'srtm_66_20.tif' with rasterio.open(elevation) as src: vals = src.sample(coords) ...
user2856's user avatar
  • 65.4k
9 votes

Elevation Profile with labels on waypoints using PyQGIS

Using your xml file and matplotlib you can achieve nice results if you put some effort in it. Matplotlib plots can be tweaked to look alot like your example. The trickiest part was to calculate where ...
BERA's user avatar
  • 71.2k
8 votes

Interrupting contour lines beneath elevation labels (instead of using label buffers) using QGIS?

UPDATE: the following workaround was only needed because label masking was not possible in PDF or SVG exports. Since QGIS 3.26 selective masking is also available in high quality vector outputs: https:...
christoph's user avatar
  • 5,565
8 votes

Seeking free elevation data for Europe?

In 2016, the Japan Aerospace Exploration Agency (JAXA) released a new free 30 m (1 arcsec) resolution global topographic data set called ALOS Global Digital Surface Model "ALOS World 3D - 30m" (AW3D30)...
8 votes
Accepted

Determining if shapefile has elevation or z coordinate values stored using ArcGIS Desktop?

Your question title and content are a little ambiguous as to what you are asking. As for checking to see if a shapefile has z information, which seems to be your ultimate question, is as follows: ...
Barbarossa's user avatar
  • 5,797
8 votes
Accepted

QGIS - Lakes - Change Polygon Z values, using Single Field Value

In QGIS 3.0, run the "set z value" algorithm. Hit the button next to z value and select the field containing your desired z values.
ndawson's user avatar
  • 27.6k
7 votes
Accepted

Which is better for measuring actual ground elevation, NED or SRTM?

This is by no means an answer to your specific problem but an explanation of elevation data and vertical accuracy. Also, this all wouldn't fit in a comment. Only a select number (depending of area ...
Barbarossa's user avatar
  • 5,797
7 votes
Accepted

Inaccurate altitude GPS data with my Android?

There could be a number of problems in play here depending on where you are, what the terrain is like, and what the capabilities of your device are? If your device uses pressure sensors they may not ...
Martin Hügi's user avatar
  • 3,612
7 votes

Creating Buffer Polygon following Elevations using ArcGIS Desktop?

Workaround for what you describe in absence of spatial analyst: arcpy.Buffer_analysis("target","../buffer.shp", "100 Meters") arcpy.FeatureVerticesToPoints_management("buffer","../points.shp","ALL") ...
FelixIP's user avatar
  • 22.8k
7 votes

Getting correct elevation values from Digital Elevation Models

It's impossible to pinpoint what is going on without looking at the data per se, but a wild guess would be due to the DEM being a DSM and not a DTM. I don't know how well you know these terms, but on ...
Roberto Ribeiro's user avatar
7 votes

QGIS: Edit elevation in DTM to get correct slope of a river

Create a new shapefile having the same CRS as your DEM. Create a numeric field (Whole number or Decimal number), like heightadd, and Add to Fields List. Draw a polygon on the area you want to add ...
MrXsquared's user avatar
  • 33.8k
7 votes

How to exaggerate the elevation in QGIS 3.6?

I suggest that you use a Hillshade symbology for the SRTM and then try using Multiply blending (put the SRTM layer on top in the Layer List). You can exaggerate with Z-factor:
hexamon's user avatar
  • 2,646
7 votes
Accepted

Elevation Profile with labels on waypoints using PyQGIS

You could combine QGIS with HTML/Javascript (Highcharts or any other framework) to produce appealing elevation profiles. With the help of some Python expression functions, it's possible to use the ...
christoph's user avatar
  • 5,565
7 votes

Using gdal to interpolate elevation from a GeoTIFF

A high-level rasterstats tool is built on GDAL to fetch data from raster and vector data sources. import rasterstats from shapely.geometry import Point raster = "elevation.tif" pt = Point(...
Mike T's user avatar
  • 42k
6 votes

How to calculate mean elevation in a DEM between a specific interval?

Set environment setting extent=your DEM extent, snap raster = DEM, cell size= one for DEM. Use raster calculator expression: Con("DEM">1500,"DEM) Right click on resulting raster, Source, scroll down ...
FelixIP's user avatar
  • 22.8k
6 votes
Accepted

Update from/to Z from attributes using arcpy Update Cursor

I think you need to fix your new shape line to contain z values. newShape = arcpy.Polyline(newGeom, None, True, False) The default is false http://pro.arcgis.com/en/pro-app/arcpy/classes/polyline....
JamesLeversha's user avatar
6 votes
Accepted

Seeking alternative to Google Maps Elevation API

There is the Open-Elevation API (https://open-elevation.com/) that looks promising see https://github.com/Jorl17/open-elevation/blob/master/docs/api.md for API examples Live API sample: https://api....
George Birbilis's user avatar
6 votes
Accepted

Latitude above and below the surface of the Earth

No, latitude doesn't follow gravity (as @mkennedy notes, it follows the normal to the ellipsoid). And, no, gravity doesn't follow your hyperbolic curve (nor a straight line). The simplest model for ...
cffk's user avatar
  • 3,241
6 votes

Calculate pixel value in arcmap

You will be able to do the calculations using the Raster Calculator with the following syntax: float("DEM_raster" * 3.2808) This will ensure the calculations are floating point accuracy rather than ...
Aaron's user avatar
  • 51.6k
6 votes
Accepted

Creating color physical map using SRTM V2 GeoTIFF tiles in QGIS

The area around the Caspian Sea is below sea (ocean) level. Baku, capital of Azerbaijan, is 28m below sea level. So using one single color ramp applied to a Digital Elevation Model that represents ...
Babel's user avatar
  • 70.4k
5 votes

Modifying DEM elevation data in QGIS using a polygon

This is actually quite easy (I do it frequently in exactly the same scenario as you're describing) but isn't well documented. What you need to do is to use the rasterise tool. What you need to do is: ...
Ed Rollason's user avatar
  • 3,878
5 votes

Free Digital Elevation (Terrain) Model of Europe or Germany

For Germany you can order the DGM10 from the Federal Agency for Cartogrpahy. The Official Elevation Datasets are available in 10 m to 1000 m spatial resolution with a height accuracy of 0.5-2 m.
Kersten's user avatar
  • 9,889
5 votes

Get rivers from a DEM raster

#You can run GRASS 6.4 commands in R using the spgrass6 package require(spgrass6) # connect to existing GRASS layer location using Mac OS X loc <- initGRASS("/Applications/GRASS-6.4.app/...
Jun Folledo's user avatar
5 votes
Accepted

Converting elevations into correct units with pyproj?

Look at Proj4 String for NAD83(2011) / Louisiana South (ftUS) preserve_units=True fix the problem (pyproj silently changes '+units=' parameter) import pyproj proj2 = pyproj.Proj(init='epsg:32051',...
gene's user avatar
  • 54.7k
5 votes

Looking for the simplest way to get elevation for a give wgs84 coordinate

You can download elevation data in raster format from this url Load each tif into postgres with:- raster2pgsql -d -s 4326 -t 50x50 <TIFF>.tif <YOUR TABLE> | psql -n <YOUR DATABASE>...
CitizenFish's user avatar

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