Basic Sin wave RP in matlab

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Basic Sin wave RP in matlab

Postby ravitejadsp » Fri Aug 12, 2011 14:48

Hello Guys,
I am very much new to RP, I read something about RP in this site. Now my doubt is following.

I have seen, A sin wave generates RP only diagonal lines. The code I have written in matlab generating cross diagonal lines. Once you check it. And please tell me where I am doing mistake?

Code: Select all


N = length(x);
S = zeros(N, N);

for i = 1:N,
    S(:,i) = abs( repmat( x(i), N, 1 ) - x(:) );

%  imagesc(t, t, S)
%  axis square
imagesc(t, t, flipud(S) < thr)
axis square
colormap([1 1 1;0 0 0])
xlabel('Time'), ylabel('Time')

the above program is for thershold value (thr) = 0.05;

How to get the exact RP of sine wave?
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Re: Basic Sin wave RP in matlab

Postby sultornsanee » Fri Oct 28, 2011 18:09

I recommend to use CRP toolbox. So you can get a right RP and RQA.
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Re: Basic Sin wave RP in matlab

Postby Norbert » Fri Oct 28, 2011 21:45

The answer is that you have not embedded your time series. Without embedding you will similar dynamics in positive and negative time direction, i.e., x(i, i+1, i+2,...) = x(j, j-1, j-2, ...). This will cause diagonals perpendicular to the main diagonal. This should be explained in the Physics Reports paper as far as I remember.
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