当前位置: 首页>>代码示例>>Python>>正文


Python FactorAnalysis.score_samples方法代码示例

本文整理汇总了Python中sklearn.decomposition.FactorAnalysis.score_samples方法的典型用法代码示例。如果您正苦于以下问题:Python FactorAnalysis.score_samples方法的具体用法?Python FactorAnalysis.score_samples怎么用?Python FactorAnalysis.score_samples使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在sklearn.decomposition.FactorAnalysis的用法示例。


在下文中一共展示了FactorAnalysis.score_samples方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: test_factor_analysis

# 需要导入模块: from sklearn.decomposition import FactorAnalysis [as 别名]
# 或者: from sklearn.decomposition.FactorAnalysis import score_samples [as 别名]
def test_factor_analysis():
    # Test FactorAnalysis ability to recover the data covariance structure
    rng = np.random.RandomState(0)
    n_samples, n_features, n_components = 20, 5, 3

    # Some random settings for the generative model
    W = rng.randn(n_components, n_features)
    # latent variable of dim 3, 20 of it
    h = rng.randn(n_samples, n_components)
    # using gamma to model different noise variance
    # per component
    noise = rng.gamma(1, size=n_features) * rng.randn(n_samples, n_features)

    # generate observations
    # wlog, mean is 0
    X = np.dot(h, W) + noise

    assert_raises(ValueError, FactorAnalysis, svd_method='foo')
    fa_fail = FactorAnalysis()
    fa_fail.svd_method = 'foo'
    assert_raises(ValueError, fa_fail.fit, X)
    fas = []
    for method in ['randomized', 'lapack']:
        fa = FactorAnalysis(n_components=n_components, svd_method=method)
        fa.fit(X)
        fas.append(fa)

        X_t = fa.transform(X)
        assert_equal(X_t.shape, (n_samples, n_components))

        assert_almost_equal(fa.loglike_[-1], fa.score_samples(X).sum())
        assert_almost_equal(fa.score_samples(X).mean(), fa.score(X))

        diff = np.all(np.diff(fa.loglike_))
        assert_greater(diff, 0., 'Log likelihood dif not increase')

        # Sample Covariance
        scov = np.cov(X, rowvar=0., bias=1.)

        # Model Covariance
        mcov = fa.get_covariance()
        diff = np.sum(np.abs(scov - mcov)) / W.size
        assert_less(diff, 0.1, "Mean absolute difference is %f" % diff)
        fa = FactorAnalysis(n_components=n_components,
                            noise_variance_init=np.ones(n_features))
        assert_raises(ValueError, fa.fit, X[:, :2])

    f = lambda x, y: np.abs(getattr(x, y))  # sign will not be equal
    fa1, fa2 = fas
    for attr in ['loglike_', 'components_', 'noise_variance_']:
        assert_almost_equal(f(fa1, attr), f(fa2, attr))

    fa1.max_iter = 1
    fa1.verbose = True
    assert_warns(ConvergenceWarning, fa1.fit, X)

    # Test get_covariance and get_precision with n_components == n_features
    # with n_components < n_features and with n_components == 0
    for n_components in [0, 2, X.shape[1]]:
        fa.n_components = n_components
        fa.fit(X)
        cov = fa.get_covariance()
        precision = fa.get_precision()
        assert_array_almost_equal(np.dot(cov, precision),
                                  np.eye(X.shape[1]), 12)
开发者ID:1992huanghai,项目名称:scikit-learn,代码行数:67,代码来源:test_factor_analysis.py


注:本文中的sklearn.decomposition.FactorAnalysis.score_samples方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。