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I'm having a bit of an issue with the proportional circle plugin for QGIS. I want to be able to adjust the start size of the circle but for the life of me I can not figure it out but I was able to do it on a previous map that I worked on. I'm on a Mac using QGIS 2.8.4. I also need to label the circle with a numerical value which I have been about to do but I need to reduce the starting size of the circle.

This is how is displays currently

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    I've always had good luck using the 'size assistant' from the Style properties dialogue box... have you tried that out?
    – Inactivated Account
    Commented Aug 14, 2016 at 21:42

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I don't use the proportional circles plugin bu can suggest an alternative method which will give you the control you need (and without creating another layer):

  1. In your polygon style, add another symbol layer
  2. Change the symbol layer from 'simple fill' to 'centroid fill'
  3. Select the new 'simple marker' (you may need to expand down from 'Centroid Fill' in the symbol layers window) and set the size to be proportional by clicking the Data Defined Override button at the right hand end of the size box. Select Edit from the Expression section of the popup menu and create a formula. To define a start size simple begin you formula with a numeric value (or field value). So for hectares you could have an expression something like: 10 + (area/10000).
  4. Style the resultant markers to taste for transparency etc (you'll be able to make them identical to the ones in your image)
  5. Control the overall size of the markers by tweaking the formula and/or switching between millimeter or pixels etc.
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  • Doesn't this make the symbol area scale-by-diameter rather than the correct scale-by-area (as it appears to be in the screenshot)? Might be able to keep the proportions correct by modifying the formula but don't have 2.8 to hand to test. Size Assistant in newer versions (2.10+) is certainly a help here.
    – Steven Kay
    Commented Aug 15, 2016 at 12:33
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    You can use any formula you want to get the effect you desire based on the attribute you are interested in. The above is just a quick example of what you could do. So if you want to scale the symbol by total symbol area, then just tweak the formula with a bit of pythagorean theory. I had assumed the OP would provide their own formula.
    – MappaGnosis
    Commented Aug 15, 2016 at 12:57

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