I’ve been telling people that turning up the analysis resolution on their Ecotect models is a bad idea, but I’d never stopped to figure out just how bad.

This table shows the rate at which the numbers grow as you go up through the resolution steps.

	Sky subdivision	Lowest 15° x 15°	Low 10° x 10°	Medium 5° x 5°	High 4° x 3°	Highest 2° x 2°
Grid subdivisions	Number of divisions	144	324	1296	2700	8100
Low - 1	1	144	324	1296	2700	8100
Medium 5 x5	25	3600	8100	32400	67500	202500
High - 10 x 10	100	360000	810000	3240000	6750000	20250000
Full - 25 x 25	625	225000000	506250000	2025000000	4218750000	12656250000

For those of you who are a bit rusty on your powers of ten (like me), that bottom right number is 12.5 billion! That’s for each panel, so if you have a 5x5 subdivision on a grid, that’d be into the trillions of calcs for your analysis. No wonder it takes a long time.

I thought I’d check to see if I was supposed to be using British billions, or American billions, and it turns out (Long_and_short_scales) that all billions have been the same in the English speaking world since 1974!