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RQA

Posted: Sat Mar 19, 2011 07:38
by sultornsanee
After I create recurrence matrix using "crp" function and I get a recurrence matrix, can I calculate RQA from this matrix?

I read your manual but it seems all function needed "time series" as input. :?

Re: RQA

Posted: Sun Mar 20, 2011 22:59
by Norbert
yes, you can do it. for example:

Code: Select all

% create recurrence plot
X = crp(timeseries,'silent');

% get distributions of line lengths
% (actually you should apply here the Theiler window before, but I omit it for simplification)
[m l] = dl(X); % l is a list of all line lengths of diagonal lines
[m v] = tt(X); % v is a list of all line lengths of vertical lines

% recurrence rate
mean(X(:))

% determinism
sum(l(l>=lmin))/sum(X(:)) % where lmin is the minimal diagonal line length, e.g. lmin=2

% mean diagonal line length
mean(l(l>=lmin))

% maximal diagonal line length
max(l(l>=lmin))

% entropy
histL=hist(l,1:length(X));
entropy(histL(:));
for the vertical line based measures (laminarity, trapping time etc.) just use vector v instead of l

best
norbert

Re: RQA

Posted: Mon Mar 21, 2011 00:16
by sultornsanee
Thank you very much ... I will try to test your codes. :D

Re: RQA

Posted: Sat Oct 11, 2014 11:54
by Parri-Dee
After I create recurrence matrix using "crp" function and I get a recurrence matrix, can I calculate RQA from this matrix?