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

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2answers
176 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
12 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
901 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 ...
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1answer
34 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
14 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
14 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 ...
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1answer
148 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 ...
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 ...
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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 ...
4
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1answer
599 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 ...
1
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2answers
47 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, ...
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1answer
28 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
25 views

Contour Creation for Export to CAD including z values using QGIS

I have LiDAR tiles for my appropriate areas where I need to extract the contour and relevant height information for use in flood studies. I am able to draw out the contours from the data, however ...
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1answer
762 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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0answers
27 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- ...
3
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1answer
195 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 ...
3
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1answer
558 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
114 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
11 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 ...
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1answer
45 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
58 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
129 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
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1answer
59 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 ...
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1answer
21 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
56 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 ...
0
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1answer
43 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
405 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
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1answer
160 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
51 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
184 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
46 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 ...
0
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0answers
36 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
votes
1answer
68 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
60 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
votes
0answers
125 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
135 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
4
votes
2answers
4k 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
12 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
votes
1answer
131 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? ...
5
votes
2answers
197 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
79 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() ...
0
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0answers
59 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 ...
3
votes
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
47 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 ...
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1answer
322 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 ...
1
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1answer
41 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
331 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
102 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
94 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 ...