moving distance between two sets of data

Also it occurred to me that my initial explanation was not  
explicitly clear as to what the desired output is. What I am trying  
to get is a moving absolute deviation between the two sets of numbers.
The phrase "a moving absolute deviation" admits of several  
interpretations. I suggest you post the correct answer for some simple  
cases or that you be more mathematical in your description (as is  
suggested in the Posting Guide.)

set.seed(123)
  X <- sample(-5:5, 10)
  Y <- sample(-5:5, 10);

 > X
  [1] -2  2  5  4  1 -5 -3  3 -4  0
 > Y
  [1]  5 -1  1  4 -5  0 -4  3 -2  2
 > abs( tail(X,9) - head(Y,9) )
[1] 3 6 3 3 0 3 7 7 2

So this is c( abs(X[2] -Y[1]), abs( X[3]-Y[2], .....)
This is not to be confused with the mean absolute deviation, or the  
median absolute deviation which are both something different and not  
what i am after.
Again. Not a clear description (of what you do do not want), given  
that the problem involves two vectors.
________________________________________
From: David Winsemius [dwinsemius at comcast.net]
Sent: Sunday, August 19, 2012 4:03 PM
To: David Winsemius
Cc: White, William Patrick; r-help at r-project.org
Subject: Re: [R] moving distance between two sets of data

On Aug 19, 2012, at 12:58 PM, David Winsemius wrote:

On Aug 19, 2012, at 12:04 PM, White, William Patrick wrote:

On the surface this seems pretty simple, but I flummoxed. I have
two sets of numbers they bounce around zero, positive one and
negative one. They have a relationship between them, where one
diverges away from the other. I want create a second set of numbers
that tracks that divergence.

#Lets make some data like mine, kinda
Firstset <- runif(100, min = -1 , max =1)
Secondset <- runif(100, min = -1 , max =1)

#So something like:
Divergence <- abs (Firstset - Secondset)

#but this doesn't work because when Firstset is at .5 and Secondset
is at  -.25 it returns .25 instead of .75

abs( .5 - (-.25) ) should NOT return .25 so you need to produce a
better example or point to specifics in the example you offered. If
what you wanting what you are getting, then use set.seed(123) and
refer to specific values.
I meant to write:  "If you are not getting what you are wanting .... "

abs( .5 - (-.25) )
[1] 0.75

--
David.

#another possibility is:

Divergence <- abs (Firstset) - abs (Secondset)

#but when Firstset is at .5 and Secondset is at -.5 it returns 0
instead of 1

#It seems like there is a better way to do this. Any ideas?
______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

David Winsemius, MD
Alameda, CA, USA

______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

David Winsemius, MD
Alameda, CA, USA

David Winsemius, MD
Alameda, CA, USA

moving distance between two sets of data

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