This function checks if the given input is of trellis structure
[ISOK, STATUS] = ISTRELLIS(S) returns [T,''] if the given input is valid trellis structure. Otherwise ISOK is F and STATUS +indicates the reason for invalidity
+Fields in trellis structure are +numInputSymbols, (number of input symbols) +numOutputSymbols, (number of output symbols) +numStates, (number of states) +nextStates, (next state matrix) +outputs, (output matrix)
+Properties of the fields are as follows +numInputSymbols and numOutputSymbols should be a power of 2 (as data is represented in bits). +The 'nextStates' and 'outputs' fields are matrices of size 'numStates' x 'numInputSymbols' . +Each element in the 'nextStates' matrix and 'output' matrix is an integer value between zero and (numStates-1). +The (r,c) element of the 'nextStates' matrix and 'output' matrix,denotes the next state and output respectively when +the starting state is (r-1) and the input bits have decimal representation (c-1).
+To convert to decimal value, use the first input bit as the most significant bit (MSB).
+Valid trellis structure +trellis.numInputSymbols = 4; +trellis.numOutputSymbols = 4; +trellis.numStates = 3; +trellis.nextStates = [0 1 2 1;0 1 2 1; 0 1 2 1]; +trellis.outputs = [0 0 1 1;1 1 2 1; 1 0 1 1]; +[isok,status] = istrellis(trellis) + +Inavlid trellis structure +trellis.numInputSymbols = 3; +trellis.numOutputSymbols = 3; +trellis.numStates = 3; +trellis.nextStates = [0 1 2 ;0 1 2 ; 0 1 2 ]; +trellis.outputs = [0 0 1 ;1 1 2 ; 1 0 1 ]; +[isok,status] = istrellis(trellis) |  |  |