Author Topic: Synthetic Channel ∆P Question  (Read 1399 times)

Bull Winkus

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Synthetic Channel ∆P Question
« on: December 20, 2014, 04:36:35 AM »
Hey guys! Has anyone tried to come up with a synthetic channel to track change rate? I want to create a pressure change gauge that deviates from zero at the center of the scale to the minus side on descending pressure and to the plus side on ascending pressure, co-measurant with the rate of change.

I made an attempt with the difference between current pressure and the daily average, but I don't think that is the ideal formula. It only measures deviation from average.

set diff to Param1 - Param2 (where Param1 is current pressure and Param2 is daily average)
set result to diff * 4

Any ideas?
Herb

WCDev

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Re: Synthetic Channel ∆P Question
« Reply #1 on: December 20, 2014, 01:37:12 PM »
Difficult to do it at the moment - what you'd need is a way to access the pressure some time in the past and currently there's no way of doing this from Apple Script - I'll add it to the feature request list  [tup]


Bull Winkus

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Re: Synthetic Channel ∆P Question
« Reply #2 on: December 20, 2014, 03:08:47 PM »
Thanks Stu! Looking forward to using it.

Happy holidays!
Herb

WCDev

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Re: Synthetic Channel ∆P Question
« Reply #3 on: December 28, 2014, 02:58:45 PM »
Sorry Herb, I am an idiot - try this in your channel:

return PressureDelta3

(change to PressureDelta1 if you want the 1 hour delta).