diff mt_get_transmat_near.m @ 4:931e71c24aa3

Old mt_get_transmat_at is now mt_get_transmat_near;
new mt_get_transmat_at gets nearest transmat deterministically.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mt_get_transmat_near.m	Sun Feb 05 13:34:02 2012 +0000
@@ -0,0 +1,39 @@
+% mt_get_transmat_near - Get transition matrix near given point in information space.
+%
+% mt_get_transmat_near ::
+%    mt_system ~'Melody Triangle system structure',
+%    natural   ~'voice Id (1 or greater)',
+%    K:natural ~'size of transition matrix',
+%    real      ~'X-coordinate',
+%    real      ~'Y-coordinate'
+% -> [[K,K]]   ~'transition matrix',
+%    [[1,3]]   ~'information coordinates'.
+%
+% A transition matrix will be chosen at random from amongst the ones
+% within a certain radius of the target point.
+% The selected transition matrix will be shown using mt_show_transmat,
+
+
+function [T,P,I]=mt_get_transmat_at(Sys,Id,K,X,Y)
+	logK=log(K);
+	normpos = Sys.map([X;Y])';
+	target = normpos*logK;
+	tmats = Sys.transmats{K};
+	info = Sys.info{K};
+	L = size(info,1);
+
+	% distance from target
+	d2 = sum((info(:,1:2) - repmat(target,L,1)).^2,2);
+	Mask = d2<=max(min(d2)*2,0.01);
+
+	M = find(Mask);
+%	J = M(argmax(info(M,3)));
+	J = M(1+floor(length(M)*rand));
+	T = tmats(:,:,J);
+	I = info(J,:);
+	%Mask=2*int16(Mask); Mask(J)=1;
+	%set(Sys.hScat{K},'CDATA',Mask); % scatc(info,Mask,16); rotate3d on;
+	%figure(50); title(sprintf('pos: %.2f, %.2f',normpos(1), normpos(2)));
+	mt_show_transmat(Id,T,I);
+	if nargin>1, P=Sys.revmap(I(1:2)'/logK); end
+end