# Calculations with Areas

Trying to do calculations with Areas (either extracted from a list or entered in the Area From String node) and nothing seems to be working. Even a simple multiplication * 2 is not working. The node returns the error “* operator can not be applied to operands of type DynamoUnits.area and int”. Is this a unit problem or am I missing something?

Michael it sounds like it is due to inconsistent units. You are trying to multiple an area by a integer/number. You probably need to neutralise the units first so that they are consistent. Here is more info on how to do that: http://www.revitforum.org/tutorials-tips-tricks/1138-revit-inconsistent-units-how-neutralize-them.html

Paul, thanks for the reply. That’s what I thought that might be going on but if that’s true, then it means that you can’t do any calculations like that in Dynamo which doesn’t seem right. I’ve seen some videos which show area being used in formulas to calculate occupant loads. I can’t strip out the units if I can’t divide the unit. Can anyone show me how to do any type of calculation on an area? Let’s say 10 s.f. * 2.

To neutralize areas you just divide it by one. But I don’t think you even need to do that. It is working for me. What method are you using?

It looks like the LunchBox tool is using Python script to extract the areas without a unit. The native Dynamo nodes extract area with a unit. To strip out the units you need to use a function but none of the functions work with areas so I seem to be stuck. I can use the lunchbox tool but I’m really trying to understand Dynamo functionality and I also want to do this with areas extracted from Revit Areas, not just rooms.

Micahel,

The “Value” Node under units will convert it appropriately for your calculations.