delta_i_j_s

def delta(x_i, j, s, N):
        """ delta_i_j_s """
        flag = j == EMMMixPLAggregator.c(x_i, s)
        if flag and s < len(x_i):
            return 1
        elif s == N:
            found_equal = False
            for l in range(len(x_i)):
                if j == EMMMixPLAggregator.c(x_i, l):
                    found_equal = True
                    break
            if not found_equal:
                return 1
        return 0