Module:Sandbox/Andy M. Wang/Sandbox/sandbox

-- For unit tests, see [[Module:Sandbox/Andy M. Wang/Sandbox/testcases]]
local p = {}

function p.hello()
	return "Hello, world!"
end

function p.speed_of_sound(frame)
	local altitude = tonumber(frame.args[1]) -- args[0] is speed_of_sound
	local mach_table = {                                                       -- scale =
		799.5, 787.0, 774.2, 761.207051,                                       -- -3 to  0
		748.0, 734.6, 721.0, 707.0, 692.8, 678.3, 663.5, 660.1, 660.1, 660.1,  --  1 to 10
		660.1, 660.1, 660.1, 662.0, 664.3, 666.5, 668.9, 671.1, 673.4, 675.6,  -- 11 to 20
		677.9, 683.7, 689.9, 696.0, 702.1, 708.1, 714.0, 719.9, 725.8, 731.6,  -- 21 to 30
		737.3, 737.7, 737.7, 736.2, 730.5, 724.6, 718.8, 712.9, 707.0, 701.1,  -- 31 to 40
		695.0, 688.9, 682.8, 676.6, 670.4, 664.1, 657.8, 652.9, 648.3, 643.7,  -- 41 to 50
		639.1, 634.4, 629.6, 624.8, 620.0, 615.2, 613.2, 613.2, 613.2, 613.5,  -- 51 to 60
	}
	altitude = altitude or 0
	local sign = (altitude < 0) and -0.5 or 0.5
	local scale = math.floor(scale / 5000 + sign)
	scale = math.min(60, math.max(-3, scale))
	return mach_table[scale + 4] * 0.44704 .. '|' .. scale .. '|' .. sign .. '|' .. altitude -- mph converted to m/s
end

return p