예제 #1
0
    def test_index_generator( self ):
        index_generator = IndexGenerator()

        # num_dims = 2, max_level = 3 index_norm_order = 1
        num_dims = 2
        max_level = 3
        index_generator.set_parameters( num_dims, max_level, 
                                        index_norm_order = 1,
                                        priority_weight = 1. )
        index_generator.build_isotropic_index_set()
        indices = index_generator.get_all_indices()

        true_indices = [[0, 0],
                        [1, 0],
                        [2, 0],
                        [0, 1],
                        [1, 1],
                        [0, 2],
                        [1, 2],
                        [2, 1],
                        [3, 0],
                        [0, 3]]
        indices_list = []
        for i, index in enumerate( indices ):
            indices_list.append( index.uncompressed_data( num_dims ) )

        indices = unique_matrix_rows( numpy.array( indices_list ))
        true_indices =  unique_matrix_rows( numpy.array( true_indices ) )
        assert numpy.allclose( true_indices, indices )

        # num_dims = 3, max_level = 2 index_norm_order = 1
        num_dims = 3
        max_level = 2
        index_generator.set_parameters( num_dims, max_level, 
                                        index_norm_order = 1,
                                        priority_weight = 1. )
        index_generator.build_isotropic_index_set()
        indices = index_generator.get_all_indices()

        true_indices = [[0, 0, 0],
                        [1, 0, 0],
                        [0, 1, 0],
                        [0, 0, 1],
                        [2, 0, 0],
                        [1, 1, 0],
                        [0, 2, 0],
                        [1, 0, 1],
                        [0, 1, 1],
                        [0, 0, 2]]

        indices_list = []
        for i, index in enumerate( indices ):
            indices_list.append( index.uncompressed_data( num_dims ) )

        indices = unique_matrix_rows( numpy.array( indices_list ))
        true_indices =  unique_matrix_rows( numpy.array( true_indices ) )
        assert numpy.allclose( true_indices, indices )

        # num_dims = 2, max_level = 3 index_norm_order = 0.5
        num_dims = 2
        max_level = 3
        index_generator = IndexGenerator()
        index_generator.set_parameters( num_dims, max_level, 
                                        index_norm_order = 0.5,
                                        priority_weight = 1. )
        index_generator.build_isotropic_index_set()
        indices = index_generator.get_all_indices()

        true_indices = [[0, 0],
                        [1, 0],
                        [2, 0],
                        [3, 0],
                        [0, 1],
                        [0, 2],
                        [0, 3]]
        indices_list = []
        for i, index in enumerate( indices ):
            indices_list.append( index.uncompressed_data( num_dims ) )

        indices = unique_matrix_rows( numpy.array( indices_list ) )
        true_indices =  unique_matrix_rows( numpy.array( true_indices ) )
        assert numpy.allclose( true_indices, indices )

        # num_dims = 2, max_level = 6 index_norm_order = 0.5
        num_dims = 2
        max_level = 6
        index_generator = IndexGenerator()
        index_generator.set_parameters( num_dims, max_level, 
                                        index_norm_order = 0.5,
                                        priority_weight = 1. )
        index_generator.build_isotropic_index_set()
        indices = index_generator.get_all_indices()

        true_indices = [[0, 0],
                        [1, 0],
                        [2, 0],
                        [3, 0],
                        [4, 0],
                        [5, 0],
                        [6, 0],
                        [1, 1],
                        [2, 1],
                        [1, 2],
                        [0, 1],
                        [0, 2],
                        [0, 3],
                        [0, 4],
                        [0, 5],
                        [0, 6]]

        indices_list = []
        for i, index in enumerate( indices ):
            indices_list.append( index.uncompressed_data( num_dims ) )

        indices = unique_matrix_rows( numpy.array( indices_list ) )
        true_indices =  unique_matrix_rows( numpy.array( true_indices ) )
        assert numpy.allclose( true_indices, indices )
예제 #2
0
from utilities.indexing import PolynomialIndex, IndexGenerator

# num_dims = 2, max_level = 6 index_norm_order = 0.5
num_dims = 10
max_level = 30
index_generator = IndexGenerator()
index_generator.set_parameters( num_dims, max_level, index_norm_order = 0.5,
                                priority_weight = 1. )
index_generator.build_isotropic_index_set()
indices = index_generator.get_all_indices()
print index_generator.num_indices
예제 #3
0
def pce_study( build_pts, build_vals, domain, 
               test_pts, test_vals, 
               results_file = None,
               cv_file = None, solver_type = 2 ):

    num_dims = build_pts.shape[0]

    index_generator = IndexGenerator()

    poly_1d = [ LegendrePolynomial1D() ]
    basis = TensorProductBasis( num_dims, poly_1d )
    pce = PCE( num_dims, order = 0, basis = basis, func_domain = domain )

    if ( solver_type == 1 ):
        num_folds = build_pts.shape[1]
    else:
        num_folds = 20

    index_norm_orders = numpy.linspace( 0.4, 1.0, 4 )
    #solvers = numpy.array( [solver_type], numpy.int32 )
    #cv_params_grid_array = cartesian_product( [solvers,orders] )
    cv_params_grid = []
    for index_norm_order in index_norm_orders:
        level = 2
        # determine what range of orders to consider. 
        # spefically consider any order that results in a pce with terms <= 3003
        while ( True ):
            index_generator.set_parameters( num_dims, level, 
                                            index_norm_order = index_norm_order )
            index_generator.build_isotropic_index_set()
            print level, index_norm_order, index_generator.num_indices
            if ( index_generator.num_indices > 3003 ):
                break
            
            cv_params = {}
            cv_params['solver'] = solver_type
            cv_params['order'] = level
            cv_params['index_norm_order'] = index_norm_order

            if ( cv_params['solver'] > 1 or 
                 index_generator.num_indices <= build_pts.shape[1] ):
                # only do least squares on over-determined systems
                cv_params_grid.append( cv_params  )
            else:
                break

            level += 1

    print cv_params_grid

    # cv_iterator = LeaveOneOutCrossValidationIterator()    
    cv_iterator = KFoldCrossValidationIterator( num_folds = num_folds )
    CV = GridSearchCrossValidation( cv_iterator, pce,
                                    use_predictor_cross_validation = True,
                                    use_fast_predictor_cross_validation = True )
    t0 = time.time()
    CV.run( build_pts, build_vals, cv_params_grid )
    time_taken = time.time() - t0
    print 'cross validation took ', time_taken, ' seconds'
    
    print "################"
    print "Best cv params: ", CV.best_cv_params
    print "Best cv score: ", CV.best_score
    print "################"

    #for i in xrange( len( CV.cv_params_set ) ):
    #    print CV.cv_params_set[i], CV.scores[i]

    best_order = CV.best_cv_params['order']
    best_index_norm_order = CV.best_cv_params['index_norm_order']

    best_pce = PCE( num_dims, 
                    order = best_order, 
                    basis = basis, 
                    func_domain = domain,
                    index_norm_order = best_index_norm_order)
    V = best_pce.vandermonde( build_pts ).T
    best_pce.set_solver( CV.best_cv_params['solver'] )
    if  cv_params['solver'] > 1 :
        best_res_tol = CV.best_cv_params['norm_residual']
        best_pce.linear_solver.residual_tolerance = best_res_tol
        
    sols, sol_metrics = best_pce.linear_solver.solve( V, build_vals )
    coeff = sols[:,-1]

    best_pce.set_coefficients( coeff )
    error = abs( build_vals - best_pce.evaluate_set( build_pts ) )
    print max( error )

    print 'Evaluating best pce at test points'
    num_test_pts = test_pts.shape[1]
    pce_vals_pred = best_pce.evaluate_set( test_pts ).T
    print test_vals.shape, pce_vals_pred.shape
    error = test_vals.squeeze() - pce_vals_pred
    linf_error = numpy.max( numpy.absolute( error ) )
    l2_error = numpy.sqrt( numpy.dot( error.T, error ) / num_test_pts )
    mean = numpy.mean( pce_vals_pred )
    var =  numpy.var( pce_vals_pred )
    pce_mean = best_pce.mean()
    pce_var = best_pce.variance()

    if results_file is not None:
        results_file.write( '%1.15e' %linf_error + ',' +  '%1.15e' %l2_error + 
                            ',' +  '%1.15e' %mean + ',' +  '%1.15e' %var + 
                            ',%1.15e' %pce_mean + ',' + '%1.15e' %pce_var + '\n')

    print "linf error: ", linf_error
    print "l2 error: ", l2_error
    print "mean: ", mean 
    print "var: ", var
    print "pce mean: ", pce_mean 
    print "pce var: ", pce_var

    me, te, ie = best_pce.get_sensitivities()
    interaction_values, interaction_terms = best_pce.get_interactions()

    show = False
    fignum = 1
    filename = 'oscillator-individual-interactions.png'
    plot_interaction_values( interaction_values, interaction_terms, title = 'Sobol indices', truncation_pct = 0.95, filename = filename, show = show,
                             fignum = fignum )
    fignum += 1
    filename = 'oscillator-dimension-interactions.png'
    plot_interaction_effects( ie, title = 'Dimension-wise joint effects', truncation_pct = 0.95, filename = filename, show = show,fignum = fignum   )
    fignum += 1
    filename = 'oscillator-main-effects.png'
    plot_main_effects( me, truncation_pct = 0.95, title = 'Main effect sensitivity indices', filename = filename, show = show, fignum = fignum  )
    fignum += 1
    filename = 'oscillator-total-effects.png'
    plot_total_effects( te, truncation_pct = 0.95, title = 'Total effect sensitivity indices', filename = filename, show = show, fignum = fignum  )
    fignum += 1

    from scipy.stats.kde import gaussian_kde
    pylab.figure( fignum  )
    pce_kde = gaussian_kde( pce_vals_pred )
    pce_kde_x = numpy.linspace( pce_vals_pred.min(), pce_vals_pred.max(), 100 )
    pce_kde_y = pce_kde( pce_kde_x )
    pylab.plot( pce_kde_x, pce_kde_y,label = 'pdf of surrogate' )
    true_kde = gaussian_kde( test_vals )
    true_kde_x = numpy.linspace( test_vals.min(), test_vals.max(), 100 )
    true_kde_y = true_kde( true_kde_x )
    pylab.plot( true_kde_x, true_kde_y, label = 'true pdf' )
    pylab.legend(loc=2)
    pylab.show()