function s = set_state(s,i,val)% Method to modify a "region" object.%% Syntax:%   "s = set_state(s,i,val)"%% Description:%   A "region" object represents a subset of states in a finite-state%   machine (FSM). A "region" object is implemented as a look-up truth table%   whose k-th entry indicates whether the k-th state in the FSM belongs to%   the region or not. This function sets the truth value of the "i"-th%   state in the region "s" to "val" and returns resulting region object. If%   "val" = 1, the "i"-th state is included in the region. If "val" = 0, the%   "i"-th state is excluded from the region. The state index "i" must be%   between 1 and "nstate" (the number of states in the FSM, see%   below).%% Examples:%   * "s = set_state(s,3,1)" includes the third state of the FSM in the%     region "s".%%   * "s = set_state(s,3,0)" excludes the third state of the FSM in the%     region "s".%% Implementation:%%   A region object consists of three fields listed below.% %   * "nstate" Number of states in the FSM.%%   * "table" Truth table (array of integers) indicating the states in%     the region %%   * "wordsize" Number of bits in each integer in the truth table array%%   Each integer word in table contains the truth value (bits) for%   "wordsize" states. Thus, the truth value for the k-th state in the FSM%   can be found in the "rem(k,wordsize)"-th bit of the%   "ceil(k/wordsize)"-th word in the table where "rem" and "ceil" are%   standard MATLAB remainder and ceiling functions,%   respectively. Currently, each word in the table is a "uint32" (unsigned%   32-bit integer) and "wordsize" is set to 32.%% See Also:%   region,isinregion,isuniverse,isempty,and,or,notif (i < 1) || (i > s.nstate)  error('State index must be between 1 to %d for this object.',s.nstate);endBIT_MAX = s.wordsize;wordidx = ceil(i/BIT_MAX);remainder = rem(i,BIT_MAX);if remainder == 0  s.table(wordidx) = double(bitset(s.table(wordidx),BIT_MAX,val));else  s.table(wordidx) = double(bitset(s.table(wordidx),remainder,val));endreturn