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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 is: How do I start working on that issue? Is there a function? Is there a step by step process?

  • I was searching around and it looks like in ArcGIS the create a TIN function creates a TIN file from points with elevation data, is there a way to make it the same in QGIS? – Edixon Gutierrez Sep 5 '14 at 19:46
  • Thanks for your answer radauxju. This is what I got following the steps: 1- Create TIN using interpolation. 2- Create contourlines from TIN. prntscr.com/4k08tc Not sure if this is the answer but is what I had in mind. Also not sure if I should marked it as an answer because @WhiteboxDev answer is a good one, the only issue is that is not working. – Edixon Gutierrez Sep 5 '14 at 20:24
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Using the Contour plugin. Generate isolines and/or filled contours a set of data points.

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There are a number of tools in QGIS for generating contours, though most require a raster input rather than vector points. As such, your best bet is to use the Contour Lines From Points tool:

Models -> [Example Models] -> Contour lines from points

You have to set up the SAGA plugin. You can do it based on the documentation: QGIS Configuring external applications.

The tool takes a vector input and generates a contour line vector. You simply need to enter your points file and the attribute containing the 'z-value', an output grid resolution, and a contour interval.

  • Thanks @WhiteboxDev, I was trying to install the plugin but I got this error, is in Spanish prntscr.com/4k0377, in the dialog box says that the plugin is broken ( more or less: El complemento está roto). – Edixon Gutierrez Sep 5 '14 at 20:12
  • @EdixonGutierrez Wish I could help you but I'm on Mac OSX, and the install for QGIS and all it's various plugins is quite different I suspect. You might consider posting another question regarding your plugin install issues. – WhiteboxDev Sep 5 '14 at 20:55
  • Is OK @WhiteboxDev, if there's somebody that can help I may ask for some help in a post here. I'm really bad with plugins bugs and so. Thanks for your answer both are correct answer, I hope I can check them both. – Edixon Gutierrez Sep 5 '14 at 21:00
  • @EdixonGutierrez, Gabor Farkas edited my answer to include a link to 'QGIS Configuring external applications', which may be able to help with your install issues. Best of luck. – WhiteboxDev Sep 5 '14 at 21:02
  • I'll give it a try. I'll post the solution to that issue if I find it. – Edixon Gutierrez Sep 5 '14 at 21:05
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Maybe it is too late to answer, but someone like me might have the same need.

I had a layer of points and I only wanted to visualize the perimeter or the contour. In QGIS 2.12 I only had to use the vector Research Tools "Polygon from Layer Extent" (from the vector menu) and voilà! The other option is to use a convex hull.In my case the first option (fastest) solve my problem as my points where regularly arranged in their extent.

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