[PD] [arduino] object & analog inputs

[Mathieu Bouchard]

On Fri, 13 Feb 2009, glerm soares wrote:

> My doubt is: how to get a *totally* not flickering analog input with 
> more than 64 steps?

Even if you have only two steps, if the value is exactly on the limit, 
even the tiniest noise will make the input flip from 0 to 1 and back, 
endlessly.

The solution is then to use some kind of modified [change] that uses a 
confidence interval.

So when you output an y, you also need to set a pair of [moses] so that it 
can find numbers outside of the interval y-c < x < y+c, or equivalently, 
abs(x-y) < c, where c is the minimum amount of change that you want to 
hear about.

If you are in a two-dimensional system, it's better to consider pairs of 
inputs together as being one thing, and so for inputs (x,y) and outputs 
(u,v), check for hypot(x-u,y-v) < c, or equivalently, (x-u)*(x-u) + 
(y-v)*(y-v) < c*c; that way, your system will be independent of the angle 
of change.

[change] itself can be replaced by a very small abstraction, and those two 
modified versions that I suggest, are not much bigger than that.

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| Mathieu Bouchard - tél:+1.514.383.3801, Montréal, Québec