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

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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.
3
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1answer
125 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 ...
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2answers
98 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?
3
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1answer
521 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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1answer
94 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 ...
2
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1answer
48 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 ...
4
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1answer
135 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
104 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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1answer
9 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. ...
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0answers
40 views

Creating an irregular points grid — one with regular along-slope distances

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 ...
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1answer
40 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 ...
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1answer
663 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 ...
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381 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?
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1answer
118 views

Digitizing contour lines from paper maps using QGIS?

Is it possible to give digitized altitude lines (from paper map) heights using QGIS?
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1answer
24 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 ...
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2answers
95 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
39 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 ...
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0answers
16 views

How to create contour lines from 4 hgt files? [duplicate]

Is it possible to draw contour line for 4 different .hgt raster in one operation ? If I load them to cover a large region, do I need to extract-> contour for each of them or is there a tool opposite ...
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0answers
24 views

Extracted Contours from DEM translated in QGIS for certain intervals

I created a DEM from several point files in QGIS. Both of these line up well with the remaining data in my file (ie cadaster, aerial imagery, etc). I wanted to generate 2m contours from the DEM ...
4
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1answer
61 views

Problem of irregular contour from a DEM

I've created contour lines every 5 meters from a grid DEM with 5x5 meter of resolution. But strangely I've obtained that the contour lines are segmented and rich of lines that goes up and down, ...
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2answers
53 views

Contour of single feature on QGIS

I'm trying to extract one single contour line at given elevation from a DEM. Taking into account that I want only one contour and not all contours with the given elevation, is there a way to do it in ...
3
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0answers
52 views

Formula for maximum coverage of a geostationary satellite based on earth station elevation

I am trying to create a javascript function to represent the maximum coverage of a geo satellite for different antenna elevations (0 degrees, 5 and 10 degrees) with 3 leaflet polylines. The result is ...
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1answer
76 views

Isohyetal Map in Arcgis

How can i create Isohyetal Map in ArcGIS10. I do have the precipitation values from number of weather stations in my area of interest. What tools should i use to create these contour lines. Thanks
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2answers
3k views

How to generate a DEM from a contour Shapefile?

I want to create a DEM from depth contours (shapefile) in QGIS. I've been trying to work out how to do this based on this previous question, notably from this link from that page, however I'm stuck, ...
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0answers
11 views

Where can I find the format specification for LSLIFF data?

I have an LSLIFF file which should contain some map contour data, and I want to write a renderer for it, but to do that I need to understand the file format. A preliminary search has not turned up ...
2
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1answer
91 views

shapefile to gmt format

I have an ESRI shapefile of the contours of my study area, and I want to convert it into a format that is acceptable by GMT, so I can make an elevation map of my study area. Is that even possible? ...
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2answers
147 views

PostGIS - Interpolate point between contours

Using PostGIS, what is the best method to interpolate the z value for points (the orange dot in the image below) located between each contour layer (blue lines and red lines in the image below)? So ...
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1answer
70 views

Problem loading the contour plugin

I have installed the contour plugin on my kubuntu 13 laptop, but when I am opening qgis (2.0.1) I get the following message: Couldn't load plugin contour due an error when calling its classFactory() ...
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0answers
48 views

Merging contour lines generated by gridded data

I have a set of gridded data, which I have used to generate contour lines based on separate values in the data. In the example provided the contour lines shown correlation coefficients. The contours ...
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2answers
1k views

Colouring areas between (vector) contours?

Is it possible to colour areas between (vector) contours without making it a DEM first? Joshdoe seems to have done so in Create filled contour map with GRASS but does not say how.
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0answers
38 views

Contour command in Spatial Ecology's GME

Has anyone been successful using the contour command from GME (Geospatial Modelling Environment)? I'm trying to create contours out of a DEM. I know you can do it in ArcGIS with 3D or Spatial Analyst ...
2
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1answer
293 views

How to create contour lines from point data?

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 ...
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1answer
215 views

QGIS contours smoothing and cleaning

Trying to utilize the contour extraction QGIS tool but having trouble creating smoothed contours. The smooth, generalize, and dissolve tools have not worked for me. Also the plugin for contours ...
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1answer
39 views

Contour generation using Interpolation - Correcting edge Effects

I utilised the Interpolation feature in QGIS to prepare contours from a DEM I had generated. Sometimes when contours intersect the edge of the DEM area, they run along the edge for some distance. ...
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1answer
219 views

How to extract elevation information from contour lines?

I'm working with OS windows 7 and using ArcGIS 10.2 and I have a point shape, which I must extract elevation for every point in it but the only useful data is a contour line shape. Not sure if it's ...
2
votes
1answer
78 views

Rasterizing Contours - How to remove 0 values

I want to convert vector contours to a DEM. From other posts, I wanted to utilise the Grass r.surf.contours tool. Initially I converted the vector contour layer to a rasterized contours using the ...
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1answer
72 views

How to extract information from a tiff file

I have a tiff file that I loaded into ArcGIS. It has roads, rivers and other features including the 600m contour for the region. I want to create a file that only shows the 600m contour. How can I do ...
3
votes
2answers
74 views

Step by step contour creation algorithm

I do seismic processing, and recently have been moving into doing contours. I have a question on the exact way this is done. I have watered down my problem so that I can understand from 'first ...
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1answer
432 views

How to generate a DEM from isolines and spot heights?

I have two shape files containing height information of a certain area and I need to create a raster DEM with GRASS using them. file 1 consists of height information in contours (isolines) file 2 ...
3
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2answers
1k views

Exporting USGS contour line shapefile to DWG or DXF?

How do I assign the Z value based on the Elevation attribute using ArcGIS 10.1 for Desktop? I've been messing with this for an hour or two now and every time the exported DWG has ZERO for z value for ...
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1answer
105 views

Error with the Contour (Spatial Analyst) tool in ArcGIS

I am having an issue with the Contour (Spatial Analyst) tool in ArcGIS. When I manually run the tool in ArcToolbox, it will sometimes say that the tool has failed, giving the following error message: ...
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3answers
555 views

Creating a Slope Map Using Contours

I am trying to create a slope map. I have many contour elevation files. I tried to use the slope tool in Arctoolbox, but it calls for raster files and I'm working with vector data. Any help with this ...
0
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1answer
125 views

How to convert excel csv file to filled contour Google Earth Map?

I have a csv file http://www.geocities.ws/radar/data2.csv. The first column is latitude. The second column is lonitude. The third column is precipitation type. 5 represents freezing rain. 15 ...
2
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1answer
98 views

QGIS contour plugin exception struck help

I am a fisheries biologist and I am just getting started with QGIS. I took a few GIS classes in college so my GIS knowledge is not extremely high. On to my question. I am trying to make a depth map ...
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1answer
29 views

Contouring surface with barriers?

I'm using ArcGIS Desktop 9.3, and I want to contour a surface with barriers. Every time the result is a polyline contour shape file which covers only a part of the surface not the whole surface. ...
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5answers
1k views

Measuring straightness of a curve segment (represented as a polyline)

I'm working on an automatic elevation contour labeling algorithm and one of the factors that I want to take into account when deciding the positions of labels is how "straight" a particular segment of ...
4
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2answers
2k views

Simplify Raster Contours ArcGIS 10

Does anybody know a way to simplify a number of contour polylines derived from a raster dataset? I need to generate a map that shows contour polylines at relatively small scale. With the contour ...
0
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1answer
64 views

gdal_contour transparent contour as png

I started using the GDAL Library in a c++ project. It is a great library, but I am a bit stuck right now with different aspects of it. What is the best way to use gdal_contour in my c++ programm? ...
0
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1answer
117 views

How to colour contour lines in .shp file when the lines are not meeting in QGIS?

I am doing bathymetry analysis, where I would like to color the contours one by one in the case land is rising (or sea level going down). There is a comprehensive explanation about coloring contours ...
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2answers
113 views

Contours from DEM with human features

I am rather new at GIS and I would like to have some guidance on what follows. I have some DEMs derived from LiDAR data. These DEMs contain building and other human features (e.g., roads). I was ...