[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: How to extract sequenced data from an array?
From: |
fork |
Subject: |
Re: How to extract sequenced data from an array? |
Date: |
Wed, 22 Dec 2010 18:11:46 +0000 (UTC) |
User-agent: |
Loom/3.14 (http://gmane.org/) |
new_user <ghostility <at> gmail.com> writes:
>
> > Yes, xcorr looks much more appropriate than what I said. It looks like
> > you only want a vector. You may want to run xcorr in autocorrelation
> > mode on each column
>
> > c1=xcorr(X(:,1));
> > c2=xcorr(X(:,2));
>
> > then maybe correlate the two results
>
> > c=xcorr(c2,c2);
>
> > then look for peaks in c. not sure if this is the correct approach.
> > However, xcorr on a bigx2 array may well result in you having to
> > terminate the process again.
>
> I run c1=xcorr(X(:,1)); on data sample, but graph is symmetrical, suggesting
I'm not seeing native data
> positions to track down where sequenced data ends:
If I remember correctly (check me -- I wish I did more of this stuff), you can
ignore the left half of the graph, even throw it out. Then a spike at x=3000
means there is some periodicity at 3000. (I think xcorr gives you correlations
in each direction, and you don't need half of those).
> As it can be noticed from screen-shot I run gnuplot with "every 10" as I get
out of memory otherwise
If your data is discontinuous integers, you might miss periodicity this way.
Have you tried using the maximum lag parameter?
> I'm just afraid of large data sets :)
And you are in meteorology ?? well, you'll grow to love them.
- Re: How to extract sequenced data from an array?, (continued)
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Ben Abbott, 2010/12/22
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Andy Buckle, 2010/12/22
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Doug Stewart, 2010/12/22
- Re: How to extract sequenced data from an array?, Andy Buckle, 2010/12/22
- Re: How to extract sequenced data from an array?, fork, 2010/12/22
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?,
fork <=
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Doug Stewart, 2010/12/22
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Doug Stewart, 2010/12/22
- Re: How to extract sequenced data from an array?, Francesco Potortì, 2010/12/23
- Re: How to extract sequenced data from an array?, Sergei Steshenko, 2010/12/22
- Re: How to extract sequenced data from an array?, new_user, 2010/12/22
- Re: How to extract sequenced data from an array?, Doug Stewart, 2010/12/22
- Re: How to extract sequenced data from an array?, Przemek Klosowski, 2010/12/22
- Re: How to extract sequenced data from an array?, Kim Hansen, 2010/12/31