orituneWrapped.m

function f = orituneWrapped(pars,oris) 
% ORITUNE 	sum of two wrapped gaussians living on a circle, for 
% orientation tuning
% 
%		oritune([Dp, Rp, Rn, Ro, sigma], oris), where
%		Dp is the preferred direction (bet 0 and 360)
%		Rp is the response to the preferred direction;
%		Rn is the response to the opposite direction;
%		Ro is the background response (useful only in some cases)
%		sigma is the tuning width;
% 		oris are the orientations, bet 0 and 360.
%
%		orituneWrapped([Dp, Rp, Rn, Ro, sigma], 'spiel'), gives you a
%       little description of the tuning.
%
% See also: ORITUNE, FITORI, CIRCSTATS, CIRCSTATS360

% 2015 Sylvia Schroeder (based on oritune)
% part of the Matteobox toolbox

if length(pars(:))~= 5
    error('You must specify all 5 parameters');
end

Dp = pars(1); Rp = pars(2); Rn = pars(3); Ro = pars(4); sigma = pars(5);

if ischar(oris) && strcmp(oris,'spiel')
    disp(['Width at half height is ' num2str(sqrt(log(2)*2)*sigma,3) ' deg']);
    disp(['Direction index is ' num2str((Rp-Rn)/(Rp+Rn),3)]);
else
    siz = size(oris);
    oris = reshape(oris,1,[]);
    gauss1 = Rp.*sum(exp((-bsxfun(@plus,oris-Dp,(-5:5)'.*360).^2)./...
        (2*sigma^2)));
    gauss2 = Rn.*sum(exp((-bsxfun(@plus,oris-Dp+180,(-5:5)'.*360).^2)./...
        (2*sigma^2)));
    
    f = Ro + gauss1 + gauss2;
    f = reshape(f, siz);
end