function xhist = get_xhist(choice_vector)

% [XHIST] = get_xhist(CHOICE_VECTOR)
%
% Converts an input choice vector into a trajectory of values between 0 and
% 1 that represent the user's allocation of button presses to A over the
% last 40 button presses.  Uses a smooth buffer implementation
%
% Required:
%   CHOICE_VECTOR - The vector of choices given by the user (e.g. c1(:,1)')
%
% The output argument is XHIST
%
% Examples:
%   For the examples described in our project
% 
% >> xhist = get_xhist(c1(:,1)');

buffer = 0.5*ones(1,40);
xhist = zeros(size(choice_vector));

for i=1:length(choice_vector),
    buffer = [choice_vector(i) buffer(1:end-1)];
xhist(i) = mean(buffer);
buffer = xhist(i)*ones(1, 40);
end;