Python linalg.norm方法代码示例

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def preprocess_hog(digits):
	samples = []
	for img in digits:
		gx = cv2.Sobel(img, cv2.CV_32F, 1, 0)
		gy = cv2.Sobel(img, cv2.CV_32F, 0, 1)
		mag, ang = cv2.cartToPolar(gx, gy)
		bin_n = 16
		bin = np.int32(bin_n*ang/(2*np.pi))
		bin_cells = bin[:10,:10], bin[10:,:10], bin[:10,10:], bin[10:,10:]
		mag_cells = mag[:10,:10], mag[10:,:10], mag[:10,10:], mag[10:,10:]
		hists = [np.bincount(b.ravel(), m.ravel(), bin_n) for b, m in zip(bin_cells, mag_cells)]
		hist = np.hstack(hists)
		
		# transform to Hellinger kernel
		eps = 1e-7
		hist /= hist.sum() + eps
		hist = np.sqrt(hist)
		hist /= norm(hist) + eps
		
		samples.append(hist)
	return np.float32(samples)
#不能保证包括所有省份 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def doAmplification(self, W, alpha):
        self.rawAmplification = False
#        #Step 1: Get the right singular vectors
#        Mu = tde_mean(self.origDeltaCoords, W)
#        (Y, S) = tde_rightsvd(self.origDeltaCoords, W, Mu)
#        
#        #Step 2: Choose which components to amplify by a visual inspection
#        chooser = PCChooser(Y, (alpha, DEFAULT_NPCs))
#        Alpha = chooser.getAlphaVec(alpha)
        
        #Step 3: Perform the amplification
        #Add the amplified delta coordinates back to the original delta coordinates
        self.ampDeltaCoords = self.origDeltaCoords + subspace_tde_amplification(self.origDeltaCoords, self.origDeltaCoords.shape, W, alpha*np.ones((1,DEFAULT_NPCs)), self.origDeltaCoords.shape[1]/2)
        
#        self.ampDeltaCoords = self.origDeltaCoords + tde_amplifyPCs(self.origDeltaCoords, W, Mu, Y, Alpha)
#        print 'normalized error:',(linalg.norm(self.ampDeltaCoords-other_delta_coords)/linalg.norm(self.ampDeltaCoords))
#        print "Finished Amplifying"

    #Perform an amplification on the raw XYZ coordinates 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_GroupLasso_Lasso_equivalence(sparse_X, fit_intercept, normalize):
    """Check that GroupLasso with groups of size 1 gives Lasso."""
    n_features = 1000
    X, y = build_dataset(
        n_samples=100, n_features=n_features, sparse_X=sparse_X)
    alpha_max = norm(X.T @ y, ord=np.inf) / len(y)
    alpha = alpha_max / 10
    clf = Lasso(alpha, tol=1e-12, fit_intercept=fit_intercept,
                normalize=normalize, verbose=0)
    clf.fit(X, y)
    # take groups of size 1:
    clf1 = GroupLasso(alpha=alpha, groups=1, tol=1e-12,
                      fit_intercept=fit_intercept, normalize=normalize,
                      verbose=0)
    clf1.fit(X, y)

    np.testing.assert_allclose(clf1.coef_, clf.coef_, atol=1e-6)
    np.testing.assert_allclose(clf1.intercept_, clf.intercept_, rtol=1e-4) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_MultiTaskLasso(fit_intercept):
    """Test that our MultiTaskLasso behaves as sklearn's."""
    X, Y = build_dataset(n_samples=20, n_features=30, n_targets=10)
    alpha_max = np.max(norm(X.T.dot(Y), axis=1)) / X.shape[0]

    alpha = alpha_max / 2.
    params = dict(alpha=alpha, fit_intercept=fit_intercept, tol=1e-10,
                  normalize=True)
    clf = MultiTaskLasso(**params)
    clf.verbose = 2
    clf.fit(X, Y)

    clf2 = sklearn_MultiTaskLasso(**params)
    clf2.fit(X, Y)
    np.testing.assert_allclose(clf.coef_, clf2.coef_, rtol=1e-5)
    if fit_intercept:
        np.testing.assert_allclose(clf.intercept_, clf2.intercept_)

    clf.tol = 1e-7
    check_estimator(clf) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_celer_path_logreg():
    X, y = build_dataset(
        n_samples=50, n_features=100, sparse_X=True)
    y = np.sign(y)
    alpha_max = norm(X.T.dot(y), ord=np.inf) / 2
    alphas = alpha_max * np.geomspace(1, 1e-2, 10)

    tol = 1e-8
    coefs, Cs, n_iters = _logistic_regression_path(
        X, y, Cs=1. / alphas, fit_intercept=False, penalty='l1',
        solver='liblinear', tol=tol)

    _, coefs_c, gaps = celer_path(
        X, y, "logreg", alphas=alphas, tol=tol, verbose=2)

    np.testing.assert_array_less(gaps, tol)
    np.testing.assert_allclose(coefs != 0, coefs_c.T != 0)
    np.testing.assert_allclose(coefs, coefs_c.T, atol=1e-5, rtol=1e-3) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_Lasso(sparse_X, fit_intercept, positive):
    """Test that our Lasso class behaves as sklearn's Lasso."""
    X, y = build_dataset(n_samples=20, n_features=30, sparse_X=sparse_X)
    if not positive:
        alpha_max = norm(X.T.dot(y), ord=np.inf) / X.shape[0]
    else:
        alpha_max = X.T.dot(y).max() / X.shape[0]

    alpha = alpha_max / 2.
    params = dict(alpha=alpha, fit_intercept=fit_intercept, tol=1e-10,
                  normalize=True, positive=positive)
    clf = Lasso(**params)
    clf.fit(X, y)

    clf2 = sklearn_Lasso(**params)
    clf2.fit(X, y)
    np.testing.assert_allclose(clf.coef_, clf2.coef_, rtol=1e-5)
    if fit_intercept:
        np.testing.assert_allclose(clf.intercept_, clf2.intercept_)

    check_estimator(Lasso) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_matrix_3x3(self):
        # This test has been added because the 2x2 example
        # happened to have equal nuclear norm and induced 1-norm.
        # The 1/10 scaling factor accommodates the absolute tolerance
        # used in assert_almost_equal.
        A = (1 / 10) * \
            self.array([[1, 2, 3], [6, 0, 5], [3, 2, 1]], dtype=self.dt)
        assert_almost_equal(norm(A), (1 / 10) * 89 ** 0.5)
        assert_almost_equal(norm(A, 'fro'), (1 / 10) * 89 ** 0.5)
        assert_almost_equal(norm(A, 'nuc'), 1.3366836911774836)
        assert_almost_equal(norm(A, inf), 1.1)
        assert_almost_equal(norm(A, -inf), 0.6)
        assert_almost_equal(norm(A, 1), 1.0)
        assert_almost_equal(norm(A, -1), 0.4)
        assert_almost_equal(norm(A, 2), 0.88722940323461277)
        assert_almost_equal(norm(A, -2), 0.19456584790481812) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_bad_args(self):
        # Check that bad arguments raise the appropriate exceptions.

        A = self.array([[1, 2, 3], [4, 5, 6]], dtype=self.dt)
        B = np.arange(1, 25, dtype=self.dt).reshape(2, 3, 4)

        # Using `axis=<integer>` or passing in a 1-D array implies vector
        # norms are being computed, so also using `ord='fro'`
        # or `ord='nuc'` raises a ValueError.
        assert_raises(ValueError, norm, A, 'fro', 0)
        assert_raises(ValueError, norm, A, 'nuc', 0)
        assert_raises(ValueError, norm, [3, 4], 'fro', None)
        assert_raises(ValueError, norm, [3, 4], 'nuc', None)

        # Similarly, norm should raise an exception when ord is any finite
        # number other than 1, 2, -1 or -2 when computing matrix norms.
        for order in [0, 3]:
            assert_raises(ValueError, norm, A, order, None)
            assert_raises(ValueError, norm, A, order, (0, 1))
            assert_raises(ValueError, norm, B, order, (1, 2))

        # Invalid axis
        assert_raises(np.AxisError, norm, B, None, 3)
        assert_raises(np.AxisError, norm, B, None, (2, 3))
        assert_raises(ValueError, norm, B, None, (0, 1, 2)) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_matrix_3x3(self):
        # This test has been added because the 2x2 example
        # happened to have equal nuclear norm and induced 1-norm.
        # The 1/10 scaling factor accommodates the absolute tolerance
        # used in assert_almost_equal.
        A = (1 / 10) * \
            np.array([[1, 2, 3], [6, 0, 5], [3, 2, 1]], dtype=self.dt)
        assert_almost_equal(norm(A), (1 / 10) * 89 ** 0.5)
        assert_almost_equal(norm(A, 'fro'), (1 / 10) * 89 ** 0.5)
        assert_almost_equal(norm(A, 'nuc'), 1.3366836911774836)
        assert_almost_equal(norm(A, inf), 1.1)
        assert_almost_equal(norm(A, -inf), 0.6)
        assert_almost_equal(norm(A, 1), 1.0)
        assert_almost_equal(norm(A, -1), 0.4)
        assert_almost_equal(norm(A, 2), 0.88722940323461277)
        assert_almost_equal(norm(A, -2), 0.19456584790481812) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_bad_args(self):
        # Check that bad arguments raise the appropriate exceptions.

        A = array([[1, 2, 3], [4, 5, 6]], dtype=self.dt)
        B = np.arange(1, 25, dtype=self.dt).reshape(2, 3, 4)

        # Using `axis=<integer>` or passing in a 1-D array implies vector
        # norms are being computed, so also using `ord='fro'`
        # or `ord='nuc'` raises a ValueError.
        assert_raises(ValueError, norm, A, 'fro', 0)
        assert_raises(ValueError, norm, A, 'nuc', 0)
        assert_raises(ValueError, norm, [3, 4], 'fro', None)
        assert_raises(ValueError, norm, [3, 4], 'nuc', None)

        # Similarly, norm should raise an exception when ord is any finite
        # number other than 1, 2, -1 or -2 when computing matrix norms.
        for order in [0, 3]:
            assert_raises(ValueError, norm, A, order, None)
            assert_raises(ValueError, norm, A, order, (0, 1))
            assert_raises(ValueError, norm, B, order, (1, 2))

        # Invalid axis
        assert_raises(ValueError, norm, B, None, 3)
        assert_raises(ValueError, norm, B, None, (2, 3))
        assert_raises(ValueError, norm, B, None, (0, 1, 2)) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def preprocess_hog(digits):
    samples = []
    for img in digits:
        gx = cv2.Sobel(img, cv2.CV_32F, 1, 0)
        gy = cv2.Sobel(img, cv2.CV_32F, 0, 1)
        mag, ang = cv2.cartToPolar(gx, gy)
        bin_n = 16
        bin = np.int32(bin_n*ang/(2*np.pi))
        bin_cells = bin[:10,:10], bin[10:,:10], bin[:10,10:], bin[10:,10:]
        mag_cells = mag[:10,:10], mag[10:,:10], mag[:10,10:], mag[10:,10:]
        hists = [np.bincount(b.ravel(), m.ravel(), bin_n) for b, m in zip(bin_cells, mag_cells)]
        hist = np.hstack(hists)

        # transform to Hellinger kernel
        eps = 1e-7
        hist /= hist.sum() + eps
        hist = np.sqrt(hist)
        hist /= norm(hist) + eps

        samples.append(hist)
    return np.float32(samples) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def test_norm(ctx=default_context()):
    try:
        import scipy
        assert LooseVersion(scipy.__version__) >= LooseVersion('0.1')
        from scipy.linalg import norm as sp_norm
    except (AssertionError, ImportError):
        print("Could not import scipy.linalg.norm or scipy is too old. "
              "Falling back to numpy.linalg.norm which is not numerically stable.")
        from numpy.linalg import norm as sp_norm

    def l1norm(input_data, axis=0, keepdims=False):
        return np.sum(abs(input_data), axis=axis, keepdims=keepdims)
    def l2norm(input_data, axis=0, keepdims=False):
        return sp_norm(input_data, axis=axis, keepdims=keepdims)

    in_data_dim = random_sample([4,5,6], 1)[0]
    for force_reduce_dim1 in [True, False]:
        in_data_shape = rand_shape_nd(in_data_dim)
        if force_reduce_dim1:
            in_data_shape = in_data_shape[:3] + (1, ) + in_data_shape[4:]
        np_arr = np.random.uniform(-1, 1, in_data_shape).astype(np.float32)
        mx_arr = mx.nd.array(np_arr, ctx=ctx)
        for ord in [1, 2]:
            for keep_dims in [True, False]:
                for i in range(4):
                    npy_out = l1norm(np_arr, i, keep_dims) if ord == 1 else l2norm(
                        np_arr, i, keep_dims)
                    mx_out = mx.nd.norm(mx_arr, ord=ord, axis=i, keepdims=keep_dims)
                    assert npy_out.shape == mx_out.shape
                    mx.test_utils.assert_almost_equal(npy_out, mx_out.asnumpy())
                    if (i < 3):
                        npy_out = l1norm(np_arr, (i, i + 1), keep_dims) if ord == 1 else l2norm(
                            np_arr, (i, i + 1), keep_dims)
                        mx_out = mx.nd.norm(mx_arr, ord=ord, axis=(i, i + 1), keepdims=keep_dims)
                        assert npy_out.shape == mx_out.shape
                        mx.test_utils.assert_almost_equal(npy_out, mx_out.asnumpy()) 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def distance(self, vec1, vec2):
    """
    Compute distance of two vector by consine distance
    """
    super(ConsineDistance, self).distance(vec1, vec2)      #super method
    num = np.dot(vec1, vec2)
    denom = linalg.norm(vec1) * linalg.norm(vec2)
    if num == 0:
      return 1
    return - num / denom
#end ConsineDistance 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def _ecl_sim(inA, inB):
    return 1.0 / (1.0 + la.norm(inA - inB))


# 皮尔逊相关系数,范围-1->+1， 越大越相似 

# 需要导入模块: from numpy import linalg [as 别名]
# 或者: from numpy.linalg import norm [as 别名]
def _cos_sim(inA, inB):
    num = float(inB * inA.T)
    de_nom = la.norm(inA) * la.norm(inB)
    return 0.5 + 0.5 * (num / de_nom)