Contour maps depict spatially-varying values, such as elevation, by means of curves of equal value.

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1answer
417 views

Continents geometry data / extracting contours of continents from country geometry

I have an ESRI Shapefile data from Natural Earth (Admin-0 Countries). I converted it to geoJSON format. There is no world or continents geometry there, only the county one. And I'd like to extract eg. ...
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0answers
383 views

Contour tool in ArcGIS 10.1 giving syntax errors [duplicate]

I am trying to run the contour tool on a raster in 10.1 and get the following error messages? Does anyone know if this is a bug and is there a work around? ERROR 010328: Syntax error at or near ...
2
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1answer
38 views

Display coastline

I have a raster converted from shape file(tool point to raster). Can anybody prompt, how to display coastline? I can use contours, but are not focused at condition "elevation = 0". Is there any simple ...
2
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1answer
27 views

Relationship between contour interval and spatial resolution of a generated DEM

If I have contour lines with interval say 10, 5, or 2 (etc.), and I generated a DEM from them, what is the relationship between between the contour interval and the resolution of the DEM? Irrespective ...
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1answer
75 views

Creating an irregular points grid — one with regular along-slope distances [on hold]

I am currently using QGIS to try and prepare a series of equally spaced -- along the terrain slopes -- sampling points within various NVC (National Vegetation Classification) sites in the UK. I am ...
3
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0answers
48 views

Creating bathymetric contours using shoreline point data and transect point data

I have been given a set of depth points for a lake that were taken along the shoreline and along linear transects. What is the best way to use these points to interpolate/extrapolate bathymetric ...
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2answers
50 views

DEM with bathymetric contour lines in GRASS

I am trying to create a DEM from a bathymetric contour lines. Contours are in vector format and the elevation value is negative. To create the surface I have converted the contours in raster (v.to ...
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1answer
41 views

How to view .dwg group layers in ArcMap? [on hold]

I'm trying to view 3 .dwg group layers in ArcMap 10.1. Whenever I add them to the map, I get an error message that says they are missing a spatial reference. That's fine. I'm just trying to view ...
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1answer
21 views

Duplicated vertices in contour features of GRASS?

I use GRASS to produce contours from DEM (r.contours for SRTM rasters). They looks fine, but most of the line features occures to be duplicated; i.e. verticies duplicated. Here are pictures of output ...
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1answer
40 views

gdal_contour is missing lines below a certain elevation

I have a very strange problem with gdal_contour. I have a very large GeoTif of Europe and would like to generate contour-lines for that region. Everything worked fine when I had lines every 25m but ...
4
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2answers
1k views

How to create contour lines from point data using QGIS?

I'm using QGIS 2.4.0 and I have a shapefile of points with elevation data and X and Y coordinates. I'm using windows 7 OS. The idea is to create a contour line SHP using my point data. My question ...
3
votes
1answer
630 views

How calculate areas between certain contour lines in qgis?

Sorry for asking a question which I found in similar ways already here, but I am trying this for days and just got no result: How do I calculate the area between certain contour lines (e.g. 0-800, ...
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2answers
72 views

Problem with contour lines thickness in bigger zoom levels

I'm a beginner user of GDAL tools. I'd like to rasterize contour lines into Tiff file (for example such region: N47E006), everything works for quite small zoom levels e.g. 10... but the problem is ...
2
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1answer
96 views

Creating 3D terrain/model from contour lines, preferably using Open Source GIS?

I am looking to create 3D terrain from a contour map that I have (originally inside a PDF). The contour lines are able to be viewed as paths in Adobe Illustrator. There are two types of lines: 7m and ...
3
votes
1answer
325 views

Recommendations for creating contour map from depth points

I am trying to put together a safe routes map for a local lake. I have an old paper map that has a grid of various depths as points. I would like to draw contour lines through these points and create ...
1
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1answer
884 views

Import SketchUp created KML contour lines model to QGIS

There's a neat trick to create contour lines based on the GE 3D terrain using Sketch-Up. The resulting KML however is a model I have looked at ways of importing KML layers to QGIS, like it was ...
1
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1answer
200 views

QGIS Contour plugin: Creating complex isolines leads to isolated areas

I use the contour plugin (v1.1) within QGIS 2.4 to create contour lines. I have streets with different travel costs. I observe problems for streets with low travel costs if they are surrounded by ...
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0answers
37 views

Convert contour lines to DEM in ArcGIS [closed]

I've been trying without success to convert contour lines to DEM (Converting to spot heights is also a possible solution but I have not found a way for that either) using ArcGIS 10.2 (Advanced ...
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0answers
27 views

Command Grass in QGIS not work

When I use r.contour or other Grass commands in QGis, I have this error message. Why?
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0answers
137 views

Error when labelling kriging result (contour) - the input layer is not valid

I've finished kriging, creating a contour-map, representing groundwater-height in my area. By a reason I don't know, it isn't possible to label my results. Neither can I export my data to vectors: ...
0
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1answer
138 views

Do jagged contours indicate more spatial variability in a data set?

A general question when working with contours, do jagged lines indicate more spatial variability in a data set? A short background of my problem and objective: I would like to delineate neighborhoods ...
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1answer
42 views

raster topo map with gaps to DEM

I'm trying to create a DEM from this raster map: I managed to clean all the shapes and text. I tried to write a program which finds the curve pieces and connects them. But, I realized that it is ...
2
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1answer
52 views

Postgis 2.1: ERROR: Shell is not a line - SQL state: XX000

My current setup is PostgreSQL 9.3.6 & PostGIS 2.1.5 I have a table with contour lines (multilinestrings) that I wish to group by the attribute 'elevation', and make polygons out of them. The ...
0
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1answer
51 views

Exporting linework layer with 'altitude' attribute in QGIS to DXF with lines raised in z according to altitude attribute?

I have contours which I have brought into QGIS from a GEOjson - the lines have an attribute of 'altitude'. I want to export these contour lines as a DXF with the lines raised in the zplane according ...
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0answers
39 views

Isolate contour line with a minimum number of points (to eliminate small polygons) with ArcGIS

I extracted a single contour line (altitude 3660 m) with ArcGIS. How can I eliminate small polygons ? I know how to do it with a GRASS command (generate contour lines) which simply asks for a minimum ...
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1answer
138 views

Create a DEM with 1 foot contours

I have Lidar data which contains multiple .las files for an entire quad. I have figured out which .las is the area I am looking for. I was told the data is in 1.4 meter resolution and would work to ...
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2answers
213 views

95 percent volume contour

I generated, from point data, a kernel density map using GRASS, and I would like to identify the 95% volume contour in it. Is it possible in GRASS? Thank you
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1answer
69 views

How to draw contour line between certain elevation range?

I have a raster and I want to draw contour lines just between certain elevation range. For example I want to draw contour lines between elevation 700 (m) and 1000 (m) with the interval of 10. So there ...
8
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2answers
955 views

What is the smallest contour interval possible when derived from a DTM?

I am converting a 2m DTM to contours, and would like to have the smallest interval possible. Is there a theoretical limit, or even a rule of thumb for defining contour intervals based on the ...
1
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1answer
78 views

Convert .xyz to contours?

Can anyone help me convert .xyz file to a contours? I have recieved some .xyz files from the local council and am hoping to turn them into a terrain for 3d modelling. I have tried the ASCII to feature ...
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0answers
28 views

QGIS creating contour lines ERROR 1 CPLRealloc() out of memory allocationg 416 bytes

When i try to create contour lines from raster (tiff file) in QGIS 2.6.0 Brighton i get the following message: I thought it could be irregular size of raster that causes error so i clipped it in ...
2
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0answers
52 views

Generate contour lines for big DEMs and import into PostGis

I've downloaded the SRTM DEM files for most of Europe, from both 3arc_v4.1 and 1arc_v3 versions. The first comes in 5x5 degrees tiles, the latter in 1x1. I can stitch them together with gdalbuildvrt ...
2
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3answers
1k views

Generating raster from isolines using SAGA or ArcGIS?

I have a vector dataset of mean annual precipitation polylines, and I would like to generate a raster from them. I'm not sure the best way to go about it. ArcGIS has the Polyline to Raster tool but ...
1
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1answer
2k views

How to export QGIS contour attributes in a DXF file?

I'm new to this. I have a .tiff data file that generates contours in QGIS. I save it as .dxf. The contours don't have any attributes or data. That's bad, because I want to make a 3D landscape in Revit ...
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2answers
86 views

How to make a contour map from a list of points and values? [duplicate]

I need to create a nice map with contours that represent various thematic data on a scale of a country, for instance, average temperatures in Germany. I have a list of coordinates with the values, ...
1
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1answer
40 views

Comparing 2 contour data set files

I have 2 feature class files of contour lines for an area of interest - from 2 different sources. We would like to select just one to use and I'm looking for any methods to effectively compare the ...
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0answers
36 views

Connect two contour line with calculated line lenght

Is it possible to make plugin for qgis like PEGGER for arcview 3.2? Problem is, how to make path over contour lines with a grade in percent Formula is: K= e*100/G*M ; K=10*100/0.08*10000=1.25m K- ...
1
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1answer
136 views

Surfer problem - overlapping grd bln

I have the following problems with Surfer: 1, I have a grid file and a bln but i'm not sure that they overlap each other exactly. I set the coordinate system with grd and bln! (WGS84) but there is no ...
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0answers
21 views

How to make input data matrix in flowmapper

I have problem with using flowmapper. I'm confused, how do I enter a text record? Can you give me an example of an appropriate text file? I've been doing interpolation and made a contour of the ground ...
1
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1answer
67 views

How to display steep slopes with the use of Contours?

I am using Arc Map 10.1. I have downloaded contour data as a shapefile. Is there any way to use the contours to display steep slopes so 15%-25% or 25% and greater.
2
votes
1answer
76 views

Models -> [Example Models] -> Contour lines from points: on MAC

I'm running QGIS2.6 on a Mac and can't seem to locate the "Contour Lines from Points" Example Model. Any help would be appreciated. SAGA is installed.
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2answers
152 views

Where to find the “contours from points” model in QGIS 2.6?

I can't find the example model "contours from points" in QGIS 2.6. Is there another tool for creating contours from points, besides the QGIS Contour plugin?
2
votes
1answer
66 views

How to make label show up on contour vector in QGIS? [closed]

I'm new to QGIS (version 2.6.0). I think my question should be easy to solve but I still get stuck at making labels show up on contour lines. These lines were generated from extracting raster (asc ...
1
vote
1answer
42 views

Chained rendering to create contour gives correct WMS but incorrect WFS using openlayers

I'm trying to create a contour as vector layer using this example: http://boundlessgeo.com/2013/01/chaining-rendering-transformations-in-geoserver/. My setup is GeoServer v2.5.3 and gwt-openlayers. ...
0
votes
1answer
50 views

Contours with negative values using the model example in QGIS?

I have a data set of water level ranging from -6 m below sea level to +30 meters. But when I use the model example for creating contours from points, the minimum contour value is zero (0). What can be ...
0
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0answers
427 views

How to create contours from points where points are not a grid?

With QGIS 2.01, the plugin Contour is not available. Anyone have another method to create contours from point / shapefile source, where the points are not a grid?
4
votes
1answer
239 views

Digitizing contour lines from paper maps using QGIS?

Is it possible to give digitized altitude lines (from paper map) heights using QGIS?
2
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1answer
130 views

How to reproduce contour-style labeling with rasterVis::contourplot?

I am currently working with a digital elevation model (DEM) of Mt. Kilimanjaro, Tanzania. The referring raster grid can be downloaded from DIVA-GIS (Country: Tanzania; Subject: Elevation). After ...
2
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2answers
406 views

How to calculate the area between two contour line?

I created contours by using SRTM30 data. Now I need to find area between two contours like in between 0 m to 50 m depth and 50 m to 100 m.
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0answers
56 views

Regenerate contour lost parts

I have some countour datasets where some parts were cut by labels, like this: Can these parts be regenerated? What I've tried is to create a straigth line between the dangling ends, but there are ...