%SEQUENTIAL Sequential mapping
%
% V = SEQUENTIAL(W1,W2)
% B = SEQUENTIAL(A,W)
%
% INPUT
% W,W1,W2 Mappings
% A Dataset
%
% OUTPUT
% V Sequentially combined mapping
% B Dataset
%
% DESCRIPTION
% The two mappings W1 and W2 are combined into a single mapping V. Note
% that SEQUENTIAL(W1,W2) is equivalent to W1*W2. If W2 is a mapping of
% a type 'combiner', it is called to make a combination attempt.
% SEQUENTIAL(A,W) maps the dataset A by the sequential mapping W.
%
% This routine is automatically called to execute W = W1*W2 or B = A*W2 in
% case W2 is a sequential mapping. It should not be directly called by users.
%
% SEE ALSO (<a href="http://37steps.com/prtools">PRTools Guide</a>)
% MAPPINGS, DATASETS
% Copyright: R.P.W. Duin, r.p.w.duin@37steps.com
function [w,varargout] = sequential(w1,w2,w3)
% Just necessary to inform PRMAP.
if (nargin == 0)
w = prmapping(mfilename,'combiner');
return;
end
[m1,k1] = size(w1);
[m2,k2] = size(w2);
if (~isa(w2,'prmapping'))
error('Second argument should be a mapping.')
end
if isa(w1,'prmapping')
% Definition
if isempty(w1) % treat empty mapping as unity mapping
w = w2;
elseif (iscombiner(w2))
% Execute the mapping W2.
varargout = repmat({[]},[1, max((nargout-1),0)]);
map = getmapping_file(w2);
pars = getdata(w2);
[w,varargout{:}] = feval(map,w1,pars{:});
else
% W2 is just a general mapping.
if (k1 > 0) && (m2 > 0) && (k1 ~= m2)
error('Inner mapping/data sizes do not agree.')
end
% Define the mapping type after combining W1 and W2.
if (isuntrained(w1)) || (isuntrained(w2))
mappingtype = 'untrained';
elseif (isgenerator(w2))
mappingtype = 'generator';
%elseif (isfixed(w2)) || (isfixed_cell(w2))
% mappingtype = 'fixed';
elseif (istrained(w1)) || (istrained(w2))
mappingtype = 'trained';
else
mappingtype = 'fixed';
end
if strcmp(mappingtype,'untrained')
labels = [];
size_in = 0;
size_out = 0;
elseif (m2 == 0 || k2 == 0) && (m1 ~= 0) && (k1 ~= 0)
% E.G. TRAINED * FIXED
labels = getlabels(w1);
size_in = getsize_in(w1);
size_out = getsize_out(w1);
elseif (m2 ~= 0) && (k2 ~= 0) && (m1 == 0 || k1 == 0)
% FIXED * TRAINED
labels = getlabels(w2);
size_in = getsize_in(w2);
size_out = getsize_out(w2);
elseif ~istrained(w2)
% TRAINED * FIXED
labels = getlabels(w1);
size_in = getsize_in(w1);
size_out = getsize_out(w2);
else
% TRAINED * TRAINED
labels = getlabels(w2);
size_in = getsize_in(w1);
size_out = getsize_out(w2);
end
w = prmapping(mfilename,mappingtype,{w1,w2},labels,size_in,size_out);
end
if ismapping(w) && (getbatch(w1) || getbatch(w2))
[n1,b1,o1] = getbatch(w1);
[n2,b2,o2] = getbatch(w2);
if ~n1
b12 = b2; o12 = o2;
elseif ~n2
b12 = b1; o12 = o1;
else
b12 = min(b1,b2); o12 = min(o1,o2);
end
w = setbatch(w,true,b12,o12);
end
elseif isempty(w2) % treat empty mapping as unity mapping
w = w1;
else
% Execution. We are here, when SEQUENTIAL(A,V) is called.
if nargin == 3 % needed as MAP breaks down sequential mappings
w2 = w2*w3; % restore them!
end
a = w1;
if (~isa(a,'double')) && (~isa(a,'prdataset'))
error('Just datasets or doubles can be mapped.')
end
% V can be a more complex mapping.
% v = +w2; v1 = v{1}; v2 = v{2};
[v1,v2] = getdata(w2);
if (isuntrained(v1))
if (isuntrained(v2))
u = a*v1;
w = u*(a*u*v2);
else
w = a*v1*v2;
end
else
if (isuntrained(v2)) && (~isgenerator(v1))
w = v1*(a*v1*v2);
% may be v1 changed the dimensionality, reset it:
w = setsize_in(w,size(a,2));
else
w1 = a*v1;
w = w1*v2;
%w = a*v1*v2;
featlabels = getlabels(w2);
if (isdataset(w)) && ~isempty(featlabels) && size(w,2) == size(featlabels,1)
w = setfeatlab(w,featlabels);
end
end
end
if ismapping(w)
w = setbatch(w,getbatch(w2));
end
end
return;