function Starstream = Pick_StarStream(dFCstream, region)

% FUNCTION Starstream = Pick_StarStream(dFCstream, region)

% This function takes as input: i) dFCstream is a dFCstream object generated by

% TS2dFCstream, in either 2D or 3D formats;

% ii) region is the index of a region which is the center of the sequence of star

% graphs that one wants to extract.

% The output Starstream (always in vector format, independently from input

% format) is the stream of stars extracted from dFCstream

invalidstream = 1;

if (ndims(dFCstream) == 3)

nregions = size(dFCstream,1);

nslices = size(dFCstream, 3);

Starstream = zeros((nregions-1), nslices);

for k = 1:nslices

Starstream(1:(nregions-1), k) = squeeze(dFCstream([1:(region-1), (region 1):nregions], region, k));

end

invalidstream = 0;

end

if (ndims(dFCstream) == 2)

nregions = (1 sqrt(1 8*size(dFCstream,1)))/2;

nslices = size(dFCstream, 2);

Starstream = zeros((nregions-1), nslices);

GoodRows = zeros((nregions-1),1);

k = 0;

g = 0;

for i = 1 : (nregions - 1)

for j = (i 1):nregions

k = k 1;

if (i < region)

if (j == region)

g = g 1;

GoodRows(g) = k;

end

end

if (i == region)

g = g 1;

GoodRows(g) = k;

end

end

end

Starstream = dFCstream(GoodRows, 1:nslices);

invalidstream = 0;

end

if (invalidstream)

disp('Provide a valid size dFCstream (3D or stream objects)!')

end