Does anyone know how to perform pie charts based on table values within QGIS and include them in the print outs?
Giovanni is right. I outline the process here: http://darrencope.com/2011/11/01/qgis-diagrams-pie-charts-for-symbols/
To create a diagram symbol, go to the properties for the layer in question, and click the “Diagrams” tab at the top, then check off “Display Diagrams” and set Diagram type to “Pie Chart.” You can also use “Text Diagram” but that’s another post!
You can set either a fixed size, or scale the size of the charts to an attribute value range. This is useful if you are wanting to use the size of the symbol to indicate a value, and the ‘slices’ to indicate percentages. In my case, I set the size to ’23’ and set it to scale between 0 and 30mm. This is arbitrary in my case, but you can play with it using your own data to see what works best for you.
At the bottom under “Attributes,” select each attribute you want to form a ‘slice’ of the pie, and click the ‘+’ on the right. Then select the next value, and click ‘+.’ Repeat until you are finished adding all values. In my case, I added attributes A, B, C, and D. I didn’t want to use the ID, so I left it out. You can set individual colours for each ‘slice’ here by double clicking the colour in the table. Here’s what my settings looked like: