--Developed by Luther Lloyd III 8/22/14 for use by Autosport Labs Community
--Copy this text into the scripting window of Race Analyzer
--Edit the gear ratios to mathc your car
--Add another gear row if needed for 6th gear or delete extraneous ones



--below values are constants for the vehicle
local 1stGear = 3.5
local 2ndGear = 2.7
local 3rdGear = 2.0
local 4thGear = 1.4
local 5thGear = 0.9
local FinalDrive = 3.21
--diameter in inches
local TireDia = 25.0  
--allowable error of gear ratio to allow for measurement variation
local gearErr = 0.1
local rpmSpeedRatio = 0
--initialized to 0 so if it doesn't work you know
local gearPos = 0 --this is the gear channel variable

function onTick() --updates gear position every second by default

--assumes Pulse Input channel one is for the RPM signal and speed in MPH
local speed = getGpsSpeed()
local rpm = getTimerRpm(0)

--this part only works for firmware version 2.0 per the RCP page
gearId = addChannel("Analog1",5) --no known channel gear so using Analog1

if speed > 10 then
    --makes sure your rolling so as not to divide by 0 
    
    rpmSpeedRatio = (rpm/speed)/(FinalDrive*1056/(TireDia*3.14159))

    if ((1stGear - rpmSpeedRatio)^2) < (gearErr^2) then gearPos = 1 end
    if ((2ndGear - rpmSpeedRatio)^2) < (gearErr^2) then gearPos = 2 end
    if ((3rdGear - rpmSpeedRatio)^2) < (gearErr^2) then gearPos = 3 end
    if ((4thGear - rpmSpeedRatio)^2) < (gearErr^2) then gearPos = 4 end
    if ((5thGear - rpmSpeedRatio)^2) < (gearErr^2) then gearPos = 5 end

else gearPos = 0 end

setChannel(gearId, gearPos) --outputs to virtual channel

end