def test_markov_chain(): # initialization and initial state (take n>=10000 to challenge the numerics) n = 100 mc = MarkovChain(mkm.line_lazy_transition_matrix(n)) assert(mc.get_n() == n) assert(mc.stationary_known() == False) assert(mc.get_stationary() == None) assert(mc.num_distributions() == 0) # distributions mc.add_distributions(mkm.delta_distribution(n,0)) assert (mc.get_distribution(0) == mkm.delta_distribution(n,0)).all() mc.add_random_delta_distributions(2) mc.add_distributions(mkm.delta_distribution(n,n-1)) assert(mc.num_distributions() == 4) # iterations assert(mc.last_iteration_time(1) == 0) assert (mc.closest_iteration_time(0,0) == 0) assert (mc.closest_iteration_time(0,5) == 0) # iterate mc.iterate_distributions([0],2) # this one will determine the stationary distribution assert(mc.last_iteration_time(0) == 2) assert(mc.next_iteration_time(0,1) == 2) mc.iterate_distributions([0,1,3],5) mc.iterate_distributions_to_stationarity([0,2]) mc.iterate_all_distributions_to_stationarity() # assert iteration time and prev & next iteration time mc.assert_iteration([0], 99) mc.assert_iteration([0], 101) assert(mc.previous_iteration_time(0,100) == 99) assert(mc.next_iteration_time(0,100) == 101) # stationary distribution # mixing (x,tv) = mc.distribution_tv_mixing(1) mc.compute_tv_mixing() # path sampling path = mc.sample_path(1,10) assert(path[0] == 1) assert(len(path) == 10) # print mc.print_info()
def tets_distributions(): # not distributions d = numpy.ones((3,3)) assert(mkm.is_distribution(d) == False) d = mkm.delta_distribution(10) d[1] = 1 assert(mkm.is_distribution(d) == False) assert(mkm.is_distribution(mkm.delta_distribution(10),n=11) == False) assert(mkm.is_distribution(mkm.delta_distribution(10),n=10) == True) assert(mkm.relative_error(numpy.array([0.0001,1,1e-16]),numpy.array([0.001,1,1e-16]))>8.0)
def test_markov_chain(): # initialization and initial state (take n>=10000 to challenge the numerics) n = 100 mc = MarkovChain(mkm.line_lazy_transition_matrix(n)) assert (mc.get_n() == n) assert (mc.stationary_distribution_known() == False) assert (mc.get_stationary_distribution() == None) assert (mc.num_distributions() == 0) # distributions mc.add_distributions(mkm.delta_distribution(n, 0)) assert (mc.get_distribution(0) == mkm.delta_distribution(n, 0)).all() mc.add_distributions(mkm.random_delta_distributions(n, 2)) mc.add_distributions(mkm.delta_distribution(n, n - 1)) assert (mc.num_distributions() == 4) # iterations assert (mc.last_iteration_time(1) == 0) # iterate mc.iterate_distributions( [0], 2) # this one will determine the stationary distribution assert (mc.last_iteration_time(0) == 2) assert (mc.next_iteration_time(0, 1) == 2) mc.iterate_distributions([0, 1, 3], 5) mc.iterate_distributions_to_stationarity([0, 2]) mc.iterate_all_distributions_to_stationarity() # stationary distribution # mixing (x, tv) = mc.distribution_tv_mixing(1) mc.compute_tv_mixing() # print some stuff mc.print_info()
def test_markov_chain(): # initialization and initial state (take n>=10000 to challenge the numerics) n = 100 mc = MarkovChain(mkm.line_lazy_transition_matrix(n)) assert(mc.get_n() == n) assert(mc.stationary_distribution_known() == False) assert(mc.get_stationary_distribution() == None) assert(mc.num_distributions() == 0) # distributions mc.add_distributions(mkm.delta_distribution(n,0)) assert (mc.get_distribution(0) == mkm.delta_distribution(n,0)).all() mc.add_distributions(mkm.random_delta_distributions(n,2)) mc.add_distributions(mkm.delta_distribution(n,n-1)) assert(mc.num_distributions() == 4) # iterations assert(mc.last_iteration_time(1) == 0) # iterate mc.iterate_distributions([0],2) # this one will determine the stationary distribution assert(mc.last_iteration_time(0) == 2) assert(mc.next_iteration_time(0,1) == 2) mc.iterate_distributions([0,1,3],5) mc.iterate_distributions_to_stationarity([0,2]) mc.iterate_all_distributions_to_stationarity() # stationary distribution # mixing (x,tv) = mc.distribution_tv_mixing(1) mc.compute_tv_mixing() # print some stuff mc.print_info()
# plot the total variation mixing mc.add_random_delta_distributions(1) mc.plot_tv_mixing(y_tol=0.01, threshold=0.01) ####################### BIASED LINE EXAMPLE ######################### # create the transition matrix P = mkm.line_lazy_transition_matrix(1000, p=0.51) # create the MarkovChain with the given transition matrix mc = mkm.MarkovChain(P) # add some initial distributions for i in [0,500,999]: mc.add_distributions(mkm.delta_distribution(1000,x=i)) # plot the total variation mixing mc.plot_tv_mixing(y_tol=0.01, threshold=1e-5) ####################### NBRW EXAMPLE ######################### import matplotlib.pyplot as plt # load a 6-regular graph with 50.000 nodes from file G_6_regular = nx.read_sparse6('6_regular.s6') # get the adjacency matrix A = nx.to_scipy_sparse_matrix(G_6_regular) # transition matrix for NBRW on the graph from the adjacency matrix
def test_iteration(): import numpy, time, random N = 10000 k = 10000 P = mkm.line_lazy_transition_matrix(N) P = P.transpose() P = P.tocsr() # single distribution x = mkm.delta_distribution(N,0) start = time.time() for i in xrange(k): x = P.dot(x) end = time.time() print "Python loop:" print end - start print x x = mkm.delta_distribution(N,0) start = time.time() x = mkm.matrix_vector_iteration_local(P,x,k) end = time.time() print "Python local iteration:" print end - start print x x = mkm.delta_distribution(N,0) start = time.time() x = mkm.matrix_vector_iteration_by_processes(P,x,k) end = time.time() print "Python iterating (multiple processes):" print end - start print x P = P.transpose() x = mkm.delta_distribution(N,0) start = time.time() x = mkm.iterate_distributions(P,x,k) end = time.time() print "Generic Python iteration:" print end - start print x P = P.transpose() # multiple distributions k = 10000 nd = 10 random.seed(0) x = mkm.random_delta_distributions(N,nd).transpose() start = time.time() x = mkm.matrix_vector_iteration_local(P,x,k) end = time.time() print "Python local iteration:" print end - start print x random.seed(0) x = mkm.random_delta_distributions(N,nd).transpose() start = time.time() x = mkm.matrix_vector_iteration_by_processes(P,x,k) end = time.time() print "Python iterating (multiple processes):" print end - start print x random.seed(0) P = P.transpose() x = mkm.random_delta_distributions(N,nd) start = time.time() x = mkm.iterate_distributions(P,x,k).transpose() end = time.time() print "Generic Python iteration:" print end - start print x P = P.transpose()