function [x,y,vx,vy]=get_values_from_state(s)global VMAX Map_Data Pos_Vector_Indexes Speed_Vector_Indexes% get_values_from_state: Gives the [x y vx vy] representation corresponding%                            to an element of the state vector.     % Arguments --------------------------------------------------------------%     s = the element of the state vector to be converted;% Evaluation -------------------------------------------------------------%     [x,y] = coordinates of the car with respect to X and Y axis %     [vx,vy] = speed of the car with respect to X and Y axis %--------------------------------------------------------------------------% In verbose mode, there is no difference to silent mode.%--------------------------------------------------------------------------% MDP Toolbox, INRA, BIA Toulouse, France%--------------------------------------------------------------------------% We will first determine the speed_index and position_index, that is the % place occupied by the position and speed of the car within the ordered% set of valid possibilities. Due to the structure of the state vector,% we have s=n_speed*(position_index-1)+speed_index, therefore% speed_index=(s modulo n_speed) except if s=k*n_speed, in% which case speed_index=n_speed. m=size(Map_Data,1);a=mod(s,size(Speed_Vector_Indexes,1));speed_index=zeros(size(s));speed_index(find(~a))=size(Speed_Vector_Indexes,1);speed_index(find(a))=a(find(a));position_index=1+floor((s-speed_index)/size(Speed_Vector_Indexes,1));% We will now determine the w_pos and w_speed, that is the % place occupied by the position and speed of the car within the ordered% set of all possibilities.w_pos=Pos_Vector_Indexes(position_index);w_pos=reshape(w_pos,size(s));w_speed=Speed_Vector_Indexes(speed_index);w_speed=reshape(w_speed,size(s));% We are now ready to compute x, y, vx and vy as:% (x-1)m+y=w_pos and (vx-1)*(2*VMAX+1)+vy=w_speed% We proceed in a similar fashion as above:% Caution: vx, vy are in the 1:2*VMAX+1 range, so we will need to recenter% them to -VMAX:VMAX% Determining y:a=mod(w_pos,m);y=zeros(size(s));y(find(~a))=m;y(find(a))=a(find(a));% Determining x:x=1+floor((w_pos-y)/m);    % Determining vy:a=mod(w_speed,2*VMAX+1);vy=zeros(size(s));vy(find(~a))=2*VMAX+1;vy(find(a))=a(find(a));% Determining vx:vx=1+floor((w_speed-vy)/(2*VMAX+1));% Recentering:vx=vx-VMAX-1;vy=vy-VMAX-1;