[Qgis-user] Measuring area

[Spencer Gardner]

I'm developing a Python plugin for which I need to measure the area (in acres) of every selected feature. I'm having no problem iterating through the selected features and it appears that I can use QgsDistanceArea.measurePolygon for the area measurement. I assume that the measurement is passed in the data layer's own units, so if my underlying shapefile is in feet I receive an area in square feet.

My questions:
     1 - Am I correct to assume the data are passed in the source layer's units?
     2 - Since I need this measurement in acres regardless of the source layer's unit of measure, does the API provide me an easy way to do this conversion, or will I need to read the source layer's units and then provide for all possible conversion ratios myself?

I'm handy with Python but by no means an expert so I appreciate your help.

Thanks,
Spencer Gardner
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