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I need to create a sector grid radiating out from a point of interest. Here is an example that I laboriously put together by hand:

enter image description here

I have found a couple of similar solutions in Generating dartboard shapefiles using ArcGIS Desktop and Drawing wind rose with QGIS from PostGIS? but neither exactly fit my criteria.

Ideally I need each sector to be an individual polygon (for data analysis purposes) and to be able to create this overlay for different sites using parameters to control the number of sectors and radial distances.

How do I generate these shapes in QGIS?

1 Answer 1

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(Too long for a comment but thought this might be helpful in some way.)

There is a plugin called Proportional circles which allows you create a legend broken into x number of segments (polygons) with a radius you can specify. You can download this from the menubar:

Plugins > Manage and Install Plugins...

Center your canvas to your points then click the plugin icon to open the interface. Then go to Legend only:

Proportional circles interface

You might see something like below (the horizontal lines are also polygons) with labelling enabled:

Example

You can remove those 'lines' by identifying them from the Attribute Table in the SECT field where the value is an L:

Attribute Table

As a quick example, I created a new ID field from the Field Calculator using the expression $id to create unique values. I used this to create a categorised style and label the polygons:

Result

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    Thank you that is most helpful - I was certain there must be a "standard" method to do this and this fits the bill perfectly. Sep 18, 2017 at 13:27
  • @AndrewLittle - Most welcome! Glad it was helpful :)
    – Joseph
    Sep 18, 2017 at 13:32
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    @Joseph I didn't know it, really nice effect.
    – mgri
    Sep 18, 2017 at 14:09
  • @Joseph did the $id labeling method give the result u're showing ? Does that mean the plugin generate the objects in a given order ? What if we want to label the generated polygons using another logic ?
    – Snaileater
    Sep 19, 2017 at 9:34
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    U will notice that generated polygons of a same "slice" are overlaid. In Joseph's example Polygon 3 is overlaid with 2 which is overlaid with 1. Maybe that does'nt comply with Andrew's computation needs ...
    – Snaileater
    Sep 19, 2017 at 12:06

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