--- a
+++ b/preprocessOfApneaECG/BioSigKit/Algorithms/phasespace.m
@@ -0,0 +1,88 @@
+function [Y,T]=phasespace(x,dim,tau)
+%Syntax: [Y,T]=phasespace(x,dim,tau) 
+%___________________________________ 
+%
+% The phase space reconstruction of a time series x with the Method Of Delays
+% (MOD), in embedding dimension m and for time dalay tau. 
+% 
+% Y is the trajectory matrix in the reconstructed phase space.
+% T is the phase space length.
+% x is the time series. 
+% dim is the embedding dimension.
+% tau is the time delay.
+%
+%
+% Reference:
+% Takens F (1981): Detecting strange attractors in turbulence. Lecture notes in
+% Mathematics, 898. Springer.
+%
+%
+% Alexandros Leontitsis
+% Department of Education
+% University of Ioannina
+% 45110 - Dourouti
+% Ioannina
+% Greece
+%
+% University e-mail: me00743@cc.uoi.gr
+% Lifetime e-mail: leoaleq@yahoo.com
+% Homepage: http://www.geocities.com/CapeCanaveral/Lab/1421
+%
+% 11 Mar 2001.
+
+if nargin<1 || isempty(x)==1
+   error('You should provide a time series.');
+else
+   % x must be a vector
+   if min(size(x))>1
+      error('Invalid time series.');
+   end
+   x=x(:);
+   % N is the time series length
+   N=length(x);
+end
+
+if nargin<2 || isempty(dim)==1
+    dim=2;
+else
+    % dim must be scalar
+    if sum(size(dim))>2
+        error('dim must be scalar.');
+    end
+    % dim must be an integer
+    if dim-round(dim)~=0
+        error('dim must be an integer.');
+    end
+    % dim must be positive
+    if dim<=0
+        error('dim must be positive.');
+    end
+end
+
+if nargin<3 || isempty(tau)==1
+    tau=1;
+else
+    % tau must be scalar
+    if sum(size(tau))>2
+        error('tau must be scalar.');
+    end
+    % tau must be an integer
+    if tau-round(tau)~=0
+        error('tau must be an integer.');
+    end
+    % tau must be positive
+    if tau<=0
+        error('tau must be positive.');
+    end
+end
+
+% Total points on phase space 
+T = N - (dim-1)*tau;
+
+% Initialize the phase space
+Y = zeros (T,dim);
+
+% Phase space reconstruction with MOD
+for i = 1 : T
+   Y(i,:) = x(i+(0:dim-1)*tau)';
+end