The vertical distance of a point or object above or below a reference surface or datum (generally mean sea level).
2
votes
2answers
46 views
Obtain all elevations points from a raster DEM
I need to obtain all elevation grid points from a raster DEM.
I see the steps required as:
Read in raster DEM (Arc Info Binary Grid format).
Create subset area using Points2One (see triangle area ...
0
votes
0answers
17 views
How do I add elevation data to a GeoJSON line from a GPX file?
I understand that elevation can be added as an optional third value in Coordinates (lat, long, elev) in a geojson file, but I can't find a way to actually do that from a gpx file. I've used ogr2ogr to ...
5
votes
1answer
4k views
How to calculate an elevation profile for a polyline in arcgis 10 with spatial analyst/3D analyst?
My elevation data is a floating point tif. I have a road for which I need to calculate the elevation profile, but I can´t see the tools to do this.
Can I do this with ArcGIS?
yours,
Rob
1
vote
1answer
43 views
Python GDAL: find out spikes and pits in DEM
I'm working with on a DEM (Geotiff) in Python GDAL, and I'd like to find out the spikes or pits in my terrain.
I have no idea how to proceed, does anyone have good algorithm to help me out?
Thanks,
eo
...
2
votes
1answer
48 views
Add Surface Information in 3d-analyst
One of our guys is using the "Functional Surface->Add Surface Information" feature in 3D-analyst tool in ArcMap 10.1 to add elevation data to an XY list. It's the only feature we're using from the ...
0
votes
1answer
58 views
Elevation difference
I want to get the elevation difference between two points in a river at a regular interval in ArcMap 10 ? I have a criteria to select the point, criteria is minimum distance between two points is 500m ...
0
votes
0answers
13 views
Which all columns should I add in postgresql table so that it stores elevation values and displays them in Geoserver?
I am using geoserver and postgresql. I imported raster (.tif) file to postgresql using raster2pgsql. The file thus imported creates a new table in postgresql. But when that file is previewed in ...
3
votes
1answer
104 views
Python Script for getting elevation difference between two points
I have several stream segments 1000 Km long. I need to find the elevation difference between two consecutive points of distance 1 Km starting from the upstream to downstream. How can I get the ...
5
votes
3answers
89 views
How to transform GPX-tracks into elevation-tracks with any GIS?
I have a GPS track in GPX format available from a recent bike tour and I need and want to do some analysis on the tracks. I'm wondering whether there is any way to transform the GPX data into an ...
6
votes
3answers
755 views
Raster: How to get elevation at lat/long using python?
I was wondering if anyone has some experience in getting elevation data from a raster without using ArcGIS, but rather get the information as a python list or dict?
I get my XY data as a list of ...
4
votes
1answer
81 views
What functionality exists to calculate Cut and Fill for excavation?
Does qgis have the ability to compare and quantify existing versus proposed elevations?
10
votes
3answers
2k views
How to download the entire ASTER GDEMv2 dataset?
On October, NASA released the new ASTER GDEM global dataset (30m) and I have been wanting to get my hands on it. The only problem is that it takes forever to download and I do not feel like drawing ...
0
votes
0answers
23 views
(.NET) Get DTED Data (Elevation) Between Two Points
I want to get DTED data (elevation) between two points (on a line).
Is there any built-in function for this purpose or I should implement it on my own?
What I want is similar to Linear Line of Sight ...
2
votes
1answer
72 views
Making a subsurface TIN model
I had been very glad if any of you have time to help me.
I am a student and currently writing a thesis.
In this paper I will create a 3D model of a glacier, where I will show the internal structures ...
6
votes
5answers
757 views
Is there an online tile-based elevation service?
I am working on an application that requires the elevation at a given lat/long coordinate for lots of closely spaced coordinates along any given irregular path. (The path is a trace of a ...
4
votes
2answers
121 views
Huge x,y,z dataset into oracle, possible?
I have 200 .xyz files containing 1500000 points each. Is this possible to import this dataset to oracle?
It makes a total of 300.000.000 points!!!
Background is I want to improve a FME script that ...
1
vote
1answer
62 views
How to apply DEM elevation adjustment parameters?
I have a nice DEM, created from UAV data, which I want to process further in QGIS, my platform of first choice. In order to represent the evelation of each pixel correctly, I have to adjust the ...
1
vote
2answers
298 views
extract elevation values along a line using Google Elevation API
I note that there is the Google Elevation API.
I see they have an example at the bottom showing an elevation profile for a line. Is there a premade service someone has put up on a website for me to ...
8
votes
4answers
2k views
Code to calculate elevation profile along line from a DEM
Given a DEM (Digital Elevation Model) say in and a line (x1,y1) --> (x2,y2) (paired coordinates (x,y)), how can one calculate the elevation profile or cross-section projected on that line ?
I am ...
0
votes
0answers
22 views
How to extract elevation data from DEM along a polyline [duplicate]
I've been trying to use qGIS to extract and save as an attribute the data elevation along a line, knowing that something similar is available in ArcGIS using the Spatial Analysis tool. So far, ...
1
vote
1answer
97 views
calculating terrain elevation line
I found too many hits on the web to even see the right direction to go.
I have to provide a small proxy server serving requests for a line
of terrain elevation data between two coordinates.
It is a ...
2
votes
1answer
88 views
filter / generalize elevation points on the basis of some conditions
I wanted to generalize many elevation points in a rectangular area (about 700 square km). I need to take about 3 points for square km. These points must satisfy some conditions:
One of these ...
3
votes
1answer
47 views
What function should I use to assess the degree of elevational change (rocky cliffs etc.) of a DEM?
I have a DEM of my research area and I want to assess how the topography/elevation changes. I am specifically looking to see what areas may be good suitable bat-roosting habitat so I am trying to ...
1
vote
1answer
71 views
Which horizontal unit is used on the table of the Profile Tool?
Does anyone knows what horizontal unit is used on the table of the "Profile Tool".
Vertical is in meter but I don't know about the horizontal axis.
Knowing the length of my profile, I tried to divide ...
6
votes
2answers
398 views
Elevation profile 10 km each side of a line
How can I get an elevation profile for a band of terrain?
The highest elevation within 10 km (on each side of the defined line) should be taken into account.
I hope my question is clear.
Thank you ...
0
votes
1answer
191 views
Calculate maximum and minimum elevation for a polygon layer from a DEM [duplicate]
I have a polygon layer and would like to know the min and max elevation within each polygon. My elevation layer is a digital elevation model. I'm not quite sure how to extract that information.
I am ...
11
votes
3answers
2k views
Where to download free elevation data for Europe?
Where can I find free elevation data for Europe? Please mention the available resolutions and terms of use when posting a source.
4
votes
5answers
456 views
Elevation correction ASTER GDEM2 (+10m)
My ASTER GDEM2 has a average elevation error of -10m for my area. (I testet it using 90 defferential GPS reference points and compared it with old Topo25, SRTM, and GoogleMaps).
I would like to ...
3
votes
1answer
205 views
How to get elevation with LibGeoTiff?
I'm trying to get an elevation profile from a geotif file ( downloaded from http://srtm.csi.cgiar.org/). I downloaded the libgeotiff library but i can's see any function that can return an elevation ...
3
votes
1answer
746 views
How to read GeoTIFF using PHP?
My current pet project involves creating a web service that uses the CGIAR SRTM worldwide elevation data set. Each request to the service will query for elevation data from a small geographic area.
...
2
votes
1answer
166 views
Orthogonal Height Profile along line (sextante -> v.segment, r.profile?)
While trying to find a way to find "valleys/ridges" within a DEM, I'd
like to know if there are tools, plugins or "methods" known or
available to automatically generate height profiles along a given
...
1
vote
0answers
84 views
Can Elevation Profile data in Arc's Flex Viewer 3.0 be exported?
a related thread here: google earth profile used in mashup or flex
Would like to export the elevation profile data (csv, txt, etc.) from Arc's Flex Viewer 3.0 as it creates one:
Also, if there is a ...
2
votes
3answers
1k views
How to extract elevation from .HGT file?
I want to asign a specific long/lat position on a map the elevation from SRTM3 data files, but have no idea how to find the specific value. So I want some example of how I can find in N50E14.hgt ...
11
votes
1answer
264 views
Why does GPS altitude jump sometimes?
I am currently developing a little application in Android which uses GPS.
When i click a button i start to record a "track". If i walk around i save my position every second into a file. This works ...
4
votes
1answer
232 views
Elevation graph from GPX file
I've got many GPX files in the following format:
<?xml version="1.0" encoding="utf-8"?>
<gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" ...
3
votes
2answers
299 views
Exporting DEM-derived rasters to CSV from QGIS?
I have been able to import into QGIS a set of raster topographic maps and the associated DEM raster maps. It registered the two for me. From there I have calculated the associated slope raster map. ...
2
votes
1answer
101 views
Lidar Elevations Data
I am trying to acquire a method of detecting sub cm elevation without manually measuring from the field. Can LIDAR data produce this for me? Example: A 1500 foot long pipe conveying water from one ...
1
vote
1answer
99 views
How to correlate raster map and elevation data?
I have been provided with a set of raster maps. Thanks to another helpful user here I have been able to acquire some elevation data for the same region from gis.utah.gov in asc format. Now I need to ...
4
votes
2answers
205 views
How to manually edit 16 bit GDEM elevation data on a Geotiff file
I'm building a virtual 3D terrain scenery using both satellite imagery (google maps satellite) and elevation data from GDEM Aster elevation data (geoTIFF format files).
My problem is that the ...
9
votes
3answers
397 views
What are common methods for converting raster digital elevation data to vector contours?
In researching this I have found many references to the opposite, creating elevation data from contours, but nothing regarding contour creation. Preferably, I am looking for open source solutions like ...
1
vote
0answers
74 views
Programmatically download NED tiles?
I used to download 1/3 arcsecond elevation geotiffs from extract.cr.usgs.gov using web services. But a few days ago, that stopped working, probably because USGS reorganized their site. I tried ...
1
vote
1answer
399 views
Help with technique to create contours from ASTER DEM in Phnom Penh, Cambodia
I have the ASTER version 2 DEM of Cambodia. I want to use it to create 1m contours of Phnom Penh, Cambodia. If anyone has this already please let me know. Now, onto the problems:
I am using ArcGIS ...
5
votes
1answer
160 views
Cartographic technique for detailing a 'Focus Area'
I'm working on updating a planning document. Whoever was in charge of cartography last time around used a great technique to identify and showcase focus areas (where to focus money and effort for ...
1
vote
1answer
212 views
Using SRTM data, how to get the coordinates of the peaks visible from a location?
Using SRTM data and a coordinate-altitude database of the peaks, I want to get the coordinates of the visible peaks from my location. I want to make an application similar to this.
How is this ...
3
votes
1answer
134 views
Change ellipsoid reference for altitude in a DEM
I have DEM data stored as RGF93 (Lambert-93) for lat/lon and NGF-IGN69 for altitude. I'm trying to change the reference ellipsoid for the elevation data (ultimately to NTF, but WGS84 would be fine to ...
1
vote
1answer
211 views
How to calculate an hypsographic curve of a raster trhough a DEM
I am using Arcgis 10.1.
I have a MODIS raster from the NSIDC website with a pixel resolution of 500 m and an attribute table with the fields 'VALUE' (as the code of snow, clouds, etc.) and 'COUNT' (as ...
4
votes
2answers
377 views
Converting Geocentric to Geodetic
I am only looking for a confirmation of what I believe to be true. If my explaination or conclusion is not accurate I would appreciate it if the reason can be explained to me.
Background ...
3
votes
3answers
250 views
What is Trinity High Water?
This question may be off topic, in which case I apologise.
I have a problem where water level is important and I have two water levels defined, Trinity High Water and Mean High Water springs (MHWS). ...
7
votes
1answer
533 views
PostGIS - Calculate progressive distance between points on a GPX path
I am attempting to build an elevation profile using PostGIS-PostgreSQL only.
I have imported GPX data in my PostGis database, so now I have a table full of the GPS coordinates of the track and the ...
2
votes
1answer
155 views
How can I calculate elevation from relief?
I have an SDE Raster that displays relief, but I want to display elevation. How would I go about doing this? I would really appreciate any advice or direction on how to do this.
