Python numpy.linalg.norm() Examples

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) 

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 

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) 

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)) 

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)) 

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) 

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) 

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) 

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 

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) 

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) 

def print_header_linear():
    print("{0:^15}{1:^15}{2:^15}{3:^15}{4:^15}"
          .format("Iteration", "Cost", "Cost reduction", "Step norm",
                  "Optimality")) 

def print_header_nonlinear():
    print("{0:^15}{1:^15}{2:^15}{3:^15}{4:^15}{5:^15}"
          .format("Iteration", "Total nfev", "Cost", "Cost reduction",
                  "Step norm", "Optimality")) 

def CovarianceMaatrixAdaptionEvolutionStrategyF(task, epsilon=1e-20, rnd=rand):
	lam, alpha_mu, hs, sigma0 = (4 + round(3 * log(task.D))) * 10, 2, 0, 0.3 * task.bcRange()
	mu = int(round(lam / 2))
	w = log(mu + 0.5) - log(range(1, mu + 1))
	w = w / sum(w)
	mueff = 1 / sum(w ** 2)
	cs = (mueff + 2) / (task.D + mueff + 5)
	ds = 1 + cs + 2 * max(sqrt((mueff - 1) / (task.D + 1)) - 1, 0)
	ENN = sqrt(task.D) * (1 - 1 / (4 * task.D) + 1 / (21 * task.D ** 2))
	cc, c1 = (4 + mueff / task.D) / (4 + task.D + 2 * mueff / task.D), 2 / ((task.D + 1.3) ** 2 + mueff)
	cmu, hth = min(1 - c1, alpha_mu * (mueff - 2 + 1 / mueff) / ((task.D + 2) ** 2 + alpha_mu * mueff / 2)), (1.4 + 2 / (task.D + 1)) * ENN
	ps, pc, C, sigma, M = full(task.D, 0.0), full(task.D, 0.0), eye(task.D), sigma0, full(task.D, 0.0)
	x = rnd.uniform(task.bcLower(), task.bcUpper())
	x_f = task.eval(x)
	while not task.stopCondI():
		pop_step = asarray([rnd.multivariate_normal(full(task.D, 0.0), C) for _ in range(int(lam))])
		pop = asarray([task.repair(x + sigma * ps, rnd) for ps in pop_step])
		pop_f = apply_along_axis(task.eval, 1, pop)
		isort = argsort(pop_f)
		pop, pop_f, pop_step = pop[isort[:mu]], pop_f[isort[:mu]], pop_step[isort[:mu]]
		if pop_f[0] < x_f: x, x_f = pop[0], pop_f[0]
		M = sum(w * pop_step.T, axis=1)
		ps = solve(chol(C).conj() + epsilon, ((1 - cs) * ps + sqrt(cs * (2 - cs) * mueff) * M + epsilon).T)[0].T
		sigma *= exp(cs / ds * (norm(ps) / ENN - 1)) ** 0.3
		ifix = where(sigma == inf)
		if any(ifix): sigma[ifix] = sigma0
		if norm(ps) / sqrt(1 - (1 - cs) ** (2 * (task.Iters + 1))) < hth: hs = 1
		else: hs = 0
		delta = (1 - hs) * cc * (2 - cc)
		pc = (1 - cc) * pc + hs * sqrt(cc * (2 - cc) * mueff) * M
		C = (1 - c1 - cmu) * C + c1 * (tile(pc, [len(pc), 1]) * tile(pc.reshape([len(pc), 1]), [1, len(pc)]) + delta * C)
		for i in range(mu): C += cmu * w[i] * tile(pop_step[i], [len(pop_step[i]), 1]) * tile(pop_step[i].reshape([len(pop_step[i]), 1]), [1, len(pop_step[i])])
		E, V = eig(C)
		if any(E < epsilon):
			E = fmax(E, 0)
			C = lstsq(V.T, dot(V, diag(E)).T, rcond=None)[0].T
	return x, x_f 

def test_vector_return_type(self):
        a = np.array([1, 0, 1])

        exact_types = np.typecodes['AllInteger']
        inexact_types = np.typecodes['AllFloat']

        all_types = exact_types + inexact_types

        for each_inexact_types in all_types:
            at = a.astype(each_inexact_types)

            an = norm(at, -np.inf)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, 0.0)

            with warnings.catch_warnings():
                warnings.simplefilter("ignore", RuntimeWarning)
                an = norm(at, -1)
                assert_(issubclass(an.dtype.type, np.floating))
                assert_almost_equal(an, 0.0)

            an = norm(at, 0)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, 2)

            an = norm(at, 1)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, 2.0)

            an = norm(at, 2)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, an.dtype.type(2.0)**an.dtype.type(1.0/2.0))

            an = norm(at, 4)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, an.dtype.type(2.0)**an.dtype.type(1.0/4.0))

            an = norm(at, np.inf)
            assert_(issubclass(an.dtype.type, np.floating))
            assert_almost_equal(an, 1.0) 

def _reflect_points(points, p1 = (0,0), p2 = (1,0)):
    """ Reflects points across the line formed by p1 and p2.  ``points`` may be
    input as either single points [1,2] or array-like[N][2], and will return in kind
    """
    # From http://math.stackexchange.com/questions/11515/point-reflection-across-a-line
    points = np.array(points); p1 = np.array(p1); p2 = np.array(p2);
    if np.asarray(points).ndim == 1:
        return 2*(p1 + (p2-p1)*np.dot((p2-p1),(points-p1))/norm(p2-p1)**2) - points
    if np.asarray(points).ndim == 2:
        return np.array([2*(p1 + (p2-p1)*np.dot((p2-p1),(p-p1))/norm(p2-p1)**2) - p for p in points]) 

def cosineSim(v1, v2):
    """Return the cosine similarity between v1 and v2 (numpy arrays)"""
    dot_prod = np.dot(v1, v2)
    return dot_prod / (norm(v1) * norm(v2)) 

def test_empty(self):
        assert_equal(norm([]), 0.0)
        assert_equal(norm(array([], dtype=self.dt)), 0.0)
        assert_equal(norm(atleast_2d(array([], dtype=self.dt))), 0.0) 

def test_matrix_2x2(self):
        A = matrix([[1, 3], [5, 7]], dtype=self.dt)
        assert_almost_equal(norm(A), 84 ** 0.5)
        assert_almost_equal(norm(A, 'fro'), 84 ** 0.5)
        assert_almost_equal(norm(A, 'nuc'), 10.0)
        assert_almost_equal(norm(A, inf), 12.0)
        assert_almost_equal(norm(A, -inf), 4.0)
        assert_almost_equal(norm(A, 1), 10.0)
        assert_almost_equal(norm(A, -1), 6.0)
        assert_almost_equal(norm(A, 2), 9.1231056256176615)
        assert_almost_equal(norm(A, -2), 0.87689437438234041)

        assert_raises(ValueError, norm, A, 'nofro')
        assert_raises(ValueError, norm, A, -3)
        assert_raises(ValueError, norm, A, 0) 

def cb(x):
        residuals.append(norm(b - A*x))

    # A = poisson((10,),format='csr') 

def test_vector(self):
        a = [1, 2, 3, 4]
        b = [-1, -2, -3, -4]
        c = [-1, 2, -3, 4]

        def _test(v):
            np.testing.assert_almost_equal(norm(v), 30 ** 0.5,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, inf), 4.0,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, -inf), 1.0,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, 1), 10.0,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, -1), 12.0 / 25,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, 2), 30 ** 0.5,
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, -2), ((205. / 144) ** -0.5),
                                           decimal=self.dec)
            np.testing.assert_almost_equal(norm(v, 0), 4,
                                           decimal=self.dec)

        for v in (a, b, c,):
            _test(v)

        for v in (array(a, dtype=self.dt), array(b, dtype=self.dt),
                  array(c, dtype=self.dt)):
            _test(v) 

def admm_phase2(x0, prob, rho, tol=1e-2, num_iters=1000, viol_lim=1e4):
    logging.info("Starting ADMM phase 2 with rho %.3f", rho)

    bestx = np.copy(x0)

    z = np.copy(x0)
    xs = [np.copy(x0) for i in range(prob.m)]
    us = [np.zeros(prob.n) for i in range(prob.m)]

    if prob.rho != rho:
        prob.rho = rho
        zlhs = 2*(prob.f0.P + rho*prob.m*sp.identity(prob.n)).tocsc()
        prob.z_solver = SLA.factorized(zlhs)

    last_z = None
    for t in range(num_iters):
        rhs = 2*rho*(sum(xs)-sum(us)) - prob.f0.qarray
        z = prob.z_solver(rhs)

        # TODO: parallel x/u-updates
        for i in range(prob.m):
            xs[i] = onecons_qcqp(z + us[i], prob.fi(i))
        for i in range(prob.m):
            us[i] += z - xs[i]

        # TODO: termination condition
        if last_z is not None and LA.norm(last_z - z) < tol:
            break
        last_z = z

        maxviol = max(prob.violations(z))
        logging.info("Iteration %d, violation %.3f", t, maxviol)

        if maxviol > viol_lim: break
        bestx = np.copy(prob.better(z, bestx))

    return bestx 

def check_same_solutions(tol=0.05):
    sol0 = solve_qp(P, q, G, h, solver=sparse_solvers[0])
    for solver in sparse_solvers:
        sol = solve_qp(P, q, G, h, solver=solver)
        relvar = norm(sol - sol0) / norm(sol0)
        assert relvar < tol, "%s's solution offset by %.1f%%" % (
            solver, 100. * relvar)
    for solver in dense_solvers:
        sol = solve_qp(P_array, q, G_array, h, solver=solver)
        relvar = norm(sol - sol0) / norm(sol0)
        assert relvar < tol, "%s's solution offset by %.1f%%" % (
            solver, 100. * relvar) 

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) 

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 

def create_word_vector(word, pos_embeddings):
    pos_list = twitter.pos(word, norm=True)
    word_vector = np.sum([pos_vectors.word_vec(str(pos).replace(" ", "")) for pos in pos_list], axis=0)
    return normalize(word_vector) 

def normalize(array):
    norm = la.norm(array)
    return array / norm 

def create_word_vector(word, pos_vectors):
    pos_list = twitter.pos(word, norm=True)
    word_vector = np.sum([pos_vectors.word_vec(str(pos).replace(" ", "")) for pos in pos_list], axis=0)
    return normalize(word_vector) 

def normalize(array):
    norm = la.norm(array)
    return array / norm 

def computeBoneLengths_np(pose_tensor, bones):
    pose_tensor_3d = pose_tensor.reshape(-1,3)
    length_list = [la.norm(pose_tensor_3d[bone[0]] - pose_tensor_3d[bone[1]])
                     for bone in bones]
    return length_list