Questions tagged [elevation]

The vertical distance of a point or object above or below a reference surface or datum (generally mean sea level).

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Reading elevation data from DEM files using memory mapped files? [closed]

I'm aware of GDAL libraries but am supposed to not use them. Is there a way to use mmap or memory mapped files to access the specific longitude, latitude and elevation values from a .DEM file? The ...
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33 views

Substracting raster values from 2 rasters with different cell sizes

I am working with two raster files. The first is a DEM and the second an elevation-correction file. Both files display the same geographic region. My problem is that the cell sizes of both files aren'...
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HGT Elevation vs Calculated Elevation

I wondering how to interpret the elevation calculation. Per example. We are in Canada and I use SRTM3 files. I use the GDAL library to extract my elevation, everyting is ok, except: Why (or how) the ...
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21 views

Elevation Map from Slope and Aspect Rasters

I am trying to create an elevation map (e.g., recreate a DEM) from the following input data: Slope Raster Aspect Raster ASCII file containing XYZ data points (Easting, Northing, and Elevation for ...
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40 views

Reading in AW3D30 GeoTIFF files and processing them in Python?

I am new to GIS processing, and I am using Python 3.6 to do so. My current task is to read in several files of geographic data (specifically tiles of elevation data from JAXA), combine them for my ...
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2answers
43 views

Lunar DEM elevation data scaled by 2

I am working with a DEM of the lunar south pole in QGIS. I have currently set the projection to "no projection", or Cartesian co-ordinates (origin at the pole). The horizontal locations of features ...
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1answer
22 views

Calculating elevation at point on line using ArcGIS Pro?

I have two line layers showing stormwater and sanitary sewer pipes. The attribute tables for both layers show elevations for the upstream and downstream ends of each pipe. I have a point layer ...
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44 views

Filling in holes in heightmap with lower resolution heightmaps?

I have this elevation map of the Verdal area in Norway, from the Norwegian mapping authority. The first one has a 1m resolution, but has some holes in the data. I'd like to fill in those holes with ...
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1answer
40 views

Downloading digital elevation model of United States?

I would like to download a digital elevation model of the United States, where can I do this? It doesn't need to be super detailed. But it would be nice, if was clipped at the country borders – ...
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1answer
38 views

Importing elevation data into prexisting KML in Google Earth Pro?

I am working on a project where I need the z value (elevation) of a set of data points. Is there a way to assign elevation data to a KML in Google Earth without doing it manually for each point? I ...
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1answer
24 views

ArcGIS REST API ElevationSync result is empty?

I would like to use the ArcGIS REST elevation service. Providing a list of locations I would like to receive a list of elevations relative to these locations. After some struggling with the syntax I ...
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1answer
15 views

Image Overlay 3D Adapt in Google Earth

When adding an image overlay (specifically a GeoTiff exported from QGIS), the image looks great until you turn on 3D buildings or terrain. These features pop through the image overlay, and disrupt the ...
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1answer
36 views

How do I bring the Z value to attribute table?

I have a shapefile exported from a hydraulics software that I use. The file is exported as polylines. I convert it to a point layer using the "Extract Nodes" function. The remaining piece of ...
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1answer
46 views

User-Scaled Color Relief Map to Google Earth from DTM

I have a DTM file, and my goal is to load it up onto Google Earth as a color relief map, with the colors gradient at levels I chose. I have successfully done this with RAS MAP using HEC RAS software, ...
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30 views

How to plot elevation charts from a GPX file that has elevation data

Is there a service or package that converts a GPX file into an elevation chart? I need either a CLI, a Web API, or a library/other software that could be wrapped up as a small service. The GPX ...
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23 views

Getting elevation value of point from TIFF Image in GeoTrellis

val path: String = "data/imgn19w065_13_geotiff.tif" val geoTiff: SinglebandGeoTiff = GeoTiffReader.readSingleband(path) val point : Point = Point.apply( -64.858043,18.332479); How I can read the ...
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Combining Bathymetric and Elevation Data using R?

Here is some elevation data of some islands. I wish to add depth info to the water. With the generous help of @Spacedman at Overlaying elevation data and bathymetry data in R I get: To resolve the ...
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1answer
51 views

Overlaying elevation data and bathymetry data in R?

I have two layers that cover approximately, but not exactly, the same area. One is land elevation of some islands. The other is the depth of the water around the islands. I can resolve the vertical ...
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2answers
75 views

Adding elevation to point in PyQGIS?

I am trying to add elevation to a 2D point in a QGIS 3 plugin, preferably in a concise and straightforward way. Not finding this easy. I think part of the problem is that in QGIS 3, fromPoint() has ...
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1answer
100 views

How do I add elevation data to my layer

I have a layer showing elevation curves and I'm trying to create an elevation profile using the Terrain Profile plugin. However, I only get a flat line. My guess is that I need to add Z values to the ...
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21 views

How to open G.L.O.B.E. DEM files from NOAA

I need to open a free GLOBE DEM. I have downloaded some tiles from: https://www.ngdc.noaa.gov/mgg/topo/gltiles.html, but I don't know which software should I use in order to open those files. Is ...
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17 views

Fetching elevation of one point from MapQuest API in Leaflet

I am trying to get elevation of clicked location via fetching elevation values from MapQuest elevation profile API https://developer.mapquest.com/documentation/open/elevation-api/elevation-profile/...
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1answer
74 views

GIS dataset with latitude, longitude, and elevation

Websites such as this one: https://gisgeography.com/best-free-gis-data-sources-raster-vector/ have many references to elevation data. They are all in *.jpg or other image format, however. What I need ...
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18 views

Where do I find the date for a specific NED raster?

I am looking at stream height and flooding. As there are seasonal differences in flood severity, knowing what month or general time of year of the image(s) is essential. I downloaded a 3m National ...
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23 views

New York buildings - XYZ altitude map

I am looking for a source of buildings elevation, preferably stored as 2D images (for each pixel, the intensity corresponds to the altitude in that XY). Considering the case of NY, it would be a XY ...
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1answer
67 views

Find higher elevation (10m) perpendicular point from stream network at regular interval

I have a stream network and for that network, I want to find the points at regular intervals which lie at 10m distance perpendicular from the stream.The final goal is to find the buffer of that 10m ...
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59 views

Calculating elevations using Mapquest elevation API?

I have a Leaflet map that contains options for users to draw lines, i need to enrich the drawn lines with elevation data from Mapquest elevation API. here is my code: drawData = drawnItems....
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46 views

Route creation with specific length and elevation change [closed]

I'm currently working on a project for my computer science study. The goal is to make a service that allows the user to enter a distance and elevation change which will then result in a random route (...
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2answers
81 views

QGIS: How to store the GPS coordinates in the attribute table? [duplicate]

I got vector points on a map. I already have the elevation information in the table for each vector point and the point-id. Now I want to get the GPS coordinates for each point stored in this ...
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1answer
48 views

Copy elevation from points to line

I have a vector line, but it has no z-dimension. I have some points along the line, which have the elevation included. Can I add the elevation from the points to the line at that specific point? ...
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2answers
215 views

How do I calculate the Terrain Ruggedness Index for each county in the United States in R?

I have a shapefile of US counties and high-resolution elevation data that spans the entire contiguous United States. My goal is to calculate a terrain ruggedness index for each county. The functions (...
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0answers
50 views

Converting .gri to topojson

I am making client-end javascript-powered maps in the context of web development. I am not using gdal, which I gather is a special kind of rendering software. Data source site: http://www.diva-gis....
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1answer
82 views

How to separate or cut the elevation from bathymetry raster TIFF file with vector layer coastline in QGIS 3.4.3?

I have a raster GeoTIFF file downloaded from GEBCO 2014 which contains bathymetry and elevation. I need to split in 2 layers the raster GeoTIFF file (layer: Bathymetry and layer: Elevation) using ...
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22 views

Erros in the elevation model differences [closed]

I have two DSM (one is before a landslide, and the other is after) with a spatial resolution of 10 m x 10 m in horizontal and 1 m in vertical. I subtract one from the other to get the difference in ...
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1answer
30 views

Seeking contour (topo) lines for United States?

I can find five foot contours for most areas, where can I find 1 foot or 2 foot contour lines? Prefer ArcGIS or AutoCAD but will take anything I can get.
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33 views

How can I change the elevation of a lake on a DEM so I show the lake bottom contours?

I'm studying the drainage of a lake and I have a DEM of the lake and the surrounding area. I already identified the shorelines of ancient lake levels at higher elevations, but I would like to keep ...
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1answer
165 views

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

I am new to QGIS and just need it to do a hydrolocic analysis of an area of which I later make a flow model with HEC-RAS 2D. I made it according to this tutorial: https://www.youtube.com/watch?v=Ro-...
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0answers
77 views

Complex 3D/elevation profiles in ArcMap 10.6

I'm looking to create a more informative 3D Profile than appears possible with vanilla Arc tools. Honestly I'm kinda surprised that this doesn't exist, maybe I'm searching the wrong terms. Situation: ...
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126 views

Band 1: Access window out of range in RasterIO()

I'm trying to implement a mouse_move event handler to display the elevation based on the mouse location. I'm using the ThinkGeo API to display the raster map (.tif) and gdal C# to get the elevation ...
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40 views

Summarize Elevation in ArcGIS Pro not working? [closed]

The tool Summarize Elevation is not producing the typical fields ie Min, Mean, and Max elevation field values, although fields like Dem Res, Product Name, Source, Source URL are being produced. Has ...
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1answer
74 views

Converting RTK Elevation Data to DEM?

I have a shapefile that contains elevation data. I want to eventually convert this to a slope layer. I'm assuming I have to convert to a raster, then a DEM, then slope. Is that correct? If so, ...
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2answers
194 views

How to extract Z data from a shapefile from points on another separate layer QGIS

I have two layers; one with elevation data (m), and the other with roads (derived from points via points to polyines). I want to run a spatial query that basically extracts the elevation data from the ...
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27 views

Command line to change altimetric reference with gdal

I want to convert a DEM with the following GEOGCS : GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS 84",6378137,298.257223563, AUTHORITY["EPSG","7030"]], AUTHORITY["EPSG","6326"]], ...
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2answers
71 views

Obtaining Elevation for single point from ArcGIS REST API?

I have spent quite a while trying to get the ESRI API working. Basically we would like to pass a lat, long to a service and obtain the elevation back. Our previous service stopped working - we were ...
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1answer
230 views

How can I modify DEM elevation data within QGIS using a polygon?

How can I modify an existing DEM using a polygon? I have a DEM raster with terrain varying between 355 and 365 meters. I have a polygon I've drawn over the area. Ideally, I would like to uniformly ...
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41 views

Is there a way to linear reference a line in QGis [duplicate]

Iv'e seen a number of plugin's that do things like create grids of points and such like, but what I need to do ideally is to create a line of points that follows a line geometry, and then drop those ...
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1answer
150 views

Show elevation profile from linestring's z values

I have linestring geometries with z values and I want to display them in a nice elevation profile (with x/z scaling functions, several profiles to overlay, and so on). Is there any QGIS function or ...
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1answer
75 views

Calculating meshes average within boundary?

I have mesh data of elevations. Each mesh has a value of elevation (e.g. 87, 60, 33, ...). And I also have data of administrative boundaries. I want to calculate the average of each administrative ...
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1answer
45 views

Showing roads that are below 10 ft elevations using ArcGIS Desktop?

I have point elevation data and road layers for a region. How do I show the road sections that are below 10 ft elevations? I am using ArcGIS Desktop 10.3.1.
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1answer
83 views

Reconciling elevation difference between SRTM and old US Army map in Laos?

In QGIS I georeferenced a 1970 US Army contour map for part of southern Laos (20 m intervals) with the following indicated properties: Horizontal datum Indian datum 1960 Spheroid=Everest Verical ...