Python datasets.make_circles函数代码示例

    def test_sparse(self):
        np.random.seed(10)
        thresh = 1.1

        # Do dense filtration with threshold
        data = (
            datasets.make_circles(n_samples=100)[0]
            + 5 * datasets.make_circles(n_samples=100)[0]
        )
        res0 = ripser(data, thresh=thresh)

        # Convert to sparse matrix first based on threshold,
        # then do full filtration
        D = makeSparseDM(data, thresh)
        res1 = ripser(D, distance_matrix=True)

        # The same number of edges should have been added
        assert res0["num_edges"] == res1["num_edges"]

        dgms0 = res0["dgms"]
        dgms1 = res1["dgms"]
        I10 = dgms0[1]
        I11 = dgms1[1]
        idx = np.argsort(I10[:, 0])
        I10 = I10[idx, :]
        idx = np.argsort(I11[:, 0])
        I11 = I11[idx, :]
        assert np.allclose(I10, I11)

    def test_sparse(self):
        np.random.seed(10)
        thresh = 1.1

        # Do dense filtration with threshold
        data = (
            datasets.make_circles(n_samples=100)[0]
            + 5 * datasets.make_circles(n_samples=100)[0]
        )
        rips0 = Rips(thresh=thresh, maxdim=1)
        dgms0 = rips0.fit_transform(data)

        # Convert to sparse matrix first based on threshold,
        # then do full filtration
        rips1 = Rips(maxdim=1)
        D = makeSparseDM(data, thresh)
        dgms1 = rips1.fit_transform(D, distance_matrix=True)

        # The same number of edges should have been added
        assert rips0.num_edges_ == rips1.num_edges_

        I10 = dgms0[1]
        I11 = dgms1[1]
        idx = np.argsort(I10[:, 0])
        I10 = I10[idx, :]
        idx = np.argsort(I11[:, 0])
        I11 = I11[idx, :]
        assert np.allclose(I10, I11)

def withCircleData():
    np.random.seed(0)
    X, Y = make_circles(n_samples=400, noise=.05, factor=.3)
    #plotData(X, Y, 'original-circle.png')
    #testPCA(X, Y, ncomp=2, dataset='circles')
    #myKPCA(X, Y, kernel_type='gauss', c=1, deg=2, ncomp=2, dataset='circles')
    myKPCA(X, Y, kernel_type='poly', c=1, deg=10, ncomp=2, dataset='circles')

def main():
    args = sys.argv[1:]
    
    dataset_path = None
    if args and '-save' in args:
        try: dataset_path = args[args.index('-save') + 1]
        except: dataset_path = 'dataset.p'
        
    # Generate the dataset
    print "...Generating Dataset..."
    X1, Y1 = make_circles(n_samples=800, noise=0.07, factor=0.4)
    frac0 = len(np.where(Y1 == 0)[0]) / float(len(Y1))
    frac1 = len(np.where(Y1 == 1)[0]) / float(len(Y1))
    
    print "Percentage of '0' labels:", frac0
    print "Percentage of '1' labels:", frac1

    # (Optionally) save the dataset to DATASET_PATH
    if dataset_path:
        print "...Saving dataset to {0}...".format(dataset_path)
        pickle.dump((X1, Y1, frac0, frac1), open(dataset_path, 'wb'))

    # Plot the dataset
    print "...Showing dataset in new window..."
    pl.figure(figsize=(10, 8))
    pl.subplots_adjust(bottom=.05, top=.9, left=.05, right=.95)

    pl.subplot(111)
    pl.title("Our Dataset: N=200, '0': {0} '1': {1} ".format(frac0, frac1), fontsize="large")

    pl.scatter(X1[:, 0], X1[:, 1], marker='o', c=Y1)

    pl.show()
    
    print "...Done."

def generate_data():
    def kernel(x1, x2):
        return np.array([x1, x2, 2 * x1 ** 2 + 2 * x2 ** 2])

    X, Y = make_circles(500, noise=0.12, factor=0.01)

    A = X[np.where(Y == 0)]
    B = X[np.where(Y == 1)]

    X0_orig = A[:, 0]
    Y0_orig = A[:, 1]

    X1_orig = B[:, 0]
    Y1_orig = B[:, 1]

    A = np.array([kernel(x, y) for x, y in zip(np.ravel(X0_orig), np.ravel(Y0_orig))])

    X0 = A[:, 0]
    Y0 = A[:, 1]
    Z0 = A[:, 2]

    A = np.array([kernel(x, y) for x, y in zip(np.ravel(X1_orig), np.ravel(Y1_orig))])
    X1 = A[:, 0]
    Y1 = A[:, 1]
    Z1 = A[:, 2]

    return X0, X1, Y0, Y1, Z0, Z1

def main():
	no_of_samples = 400
	
	data = []
	data.append( datasets.make_moons(n_samples=no_of_samples, noise=0.05)[0] )
	data.append( datasets.make_circles(n_samples=no_of_samples, factor=0.5, noise=0.05)[0] )
	
	# number of clusters we expect
	K = 2

	for X in data:	
		# from dataset, create adjacency, degree, and laplacian matrix
		adjacency 	= gaussianDistance( X, sigma=0.1 )
		degree 		= degreeMatrix( adjacency )
		L 			= diag(degree) - adjacency

		# perform whitening on the Laplacian matrix
		deg_05 	= diag( degree  ** -0.5 )
		L 		= deg_05.dot( L ).dot( deg_05 )

		# use eig to obtain eigenvalues and eigenvectors
		eigenvalues, eigenvectors = linalg.eig( L )

		# Sort the eigenvalues ascending, the first K zero eigenvalues represent the connected components
		idx = eigenvalues.argsort()
		eigenvalues.sort()
		evecs = eigenvectors[:, idx]
		eigenvectors = evecs[:, 0:K]
		print eigenvalues[0:K]

		color_array = ['b', 'r', 'g', 'y']

		fig = pyplot.figure( figsize=(15, 5) )
		fig.canvas.set_window_title( 'Difference between K-means and Spectral Clusterings' )

		# First perform the normal K-means on the original dataset and plot it out
		centroids, labels = scipy.cluster.vq.kmeans2( X, K )
		data = c_[X, labels]	
		ax = fig.add_subplot( 131 )
		ax.set_title('K means clustering')
		for k in range( 0, K ):
			ax.scatter( data[data[:, 2]==k, 0], data[data[:, 2]==k, 1], c=color_array[k], marker='o')

		# Then we perform spectral clustering, i.e. K-means on eigenvectors
		centroids, labels = scipy.cluster.vq.kmeans2( eigenvectors, K )
		data = c_[X, labels]	
		ax = fig.add_subplot( 132 )
		ax.set_title('Spectral clustering')
		for k in range( 0, K ):
			ax.scatter( data[data[:, 2]==k, 0], data[data[:, 2]==k, 1], c=color_array[k], marker='o')

		# Plot out the eigenvectors too
		data = c_[eigenvectors, labels]
		ax = fig.add_subplot(133)
		ax.set_title('K-eigenvectors')
		for k in range( 0, K ):
			ax.scatter( data[data[:, 2]==k, 0], data[data[:, 2]==k, 1], c=color_array[k], marker='o')

		pyplot.show()

def generate_circles():

    X1, Y1 = make_circles(n_samples=500, noise=0.07, factor=0.4)
    plt.figure(figsize=(5, 5))
    plt.scatter(X1[:, 0], X1[:, 1], c=Y1)
    plt.grid(b=True, which="major", linestyle="-", alpha=0.1, color="black")
    plt.title("Can this be solved linearly?", size=16)
    plt.show()

def main():
    n=500
    x,y=datasets.make_circles(n_samples=n,factor=.5,noise=.05)
    label=CCPMCV().fit(x).label
    print "ARI:",adjusted_rand_score(y,label)
    figure(1)
    scatter(x[:,0],x[:,1],c=label,s=50)
    show()

def generate_circles(n, y_val):
    """
    Generates a dataset where points are shaped into two circles,
    and labels them with y_val.
    """
    X,y = make_circles(n, noise=0.1)

    return (X, [y_val] * len(X))

def generate_biclass_data(data_type, random_state):
    """ Generate biclass data to classify

    arg : data_type (str) possible type of data
            choose any in ["lin_sep", "non_lin_sep", "overlap"]
            'lin_sep' : Bi-class, linearly separable data
            'non_lin_sep' : Bi-class, non linearly separable data
            'overlap' : Bi-class, non linearly separable data with class overlap

        random_state (int) seed for numpy.random
    """

    # Set seed for reproducible results
    np.random.seed(random_state)

    # Case 1 : linearly separable data
    if data_type == "lin_sep":
        mean1 = np.array([0, 2])
        mean2 = np.array([2, 0])
        cov = np.array([[0.8, 0.6], [0.6, 0.8]])
        X1 = np.random.multivariate_normal(mean1, cov, 100)
        y1 = np.ones(len(X1))
        X2 = np.random.multivariate_normal(mean2, cov, 100)
        y2 = np.ones(len(X2)) * -1
        X = np.vstack((X1, X2))
        y = np.hstack((y1, y2))

    # Case 2 : non -linearly separable data
    elif data_type == "moons":
        X, y = make_moons(n_samples=200, noise=0.2)

    elif data_type == "circles":
        X, y = make_circles(n_samples=200, noise=0.2, factor=0.5)

    # Case 3 : data with overlap between classes
    elif data_type == "overlap":
        mean1 = np.array([0, 2])
        mean2 = np.array([2, 0])
        cov = np.array([[1.5, 1.0], [1.0, 1.5]])
        X1 = np.random.multivariate_normal(mean1, cov, 100)
        y1 = np.ones(len(X1))
        X2 = np.random.multivariate_normal(mean2, cov, 100)
        y2 = np.ones(len(X2)) * -1
        X = np.vstack((X1, X2))
        y = np.hstack((y1, y2))

    assert(X.shape[0] == y.shape[0])

    # Format target to: -1 / +1
    targets = set(y.tolist())
    t1 = min(targets)
    t2 = max(targets)
    l1 = np.where(y < t2)
    l2 = np.where(y > t1)
    y[l1] = -1
    y[l2] = 1

    return X, y

def loadDatasets(linearly_separable):

    datasets = [\
                make_moons(noise=0.3, random_state=0), \
                make_circles(noise=0.2, factor=0.5, random_state=1), \
                linearly_separable \
               ]

    return datasets

def make_datasets():
    """

    :return:
    """

    return [make_moons(n_samples=200, noise=0.3, random_state=0),
            make_circles(n_samples=200, noise=0.2, factor=0.5, random_state=1),
            make_linearly_separable()]

def test_gridsearch_pipeline():
    # Test if we can do a grid-search to find parameters to separate
    # circles with a perceptron model.
    X, y = make_circles(n_samples=400, factor=0.3, noise=0.05, random_state=0)
    kpca = KernelPCA(kernel="rbf", n_components=2)
    pipeline = Pipeline([("kernel_pca", kpca), ("Perceptron", Perceptron())])
    param_grid = dict(kernel_pca__gamma=2.0 ** np.arange(-2, 2))
    grid_search = GridSearchCV(pipeline, cv=3, param_grid=param_grid)
    grid_search.fit(X, y)
    assert_equal(grid_search.best_score_, 1)

def test_random_trees_dense_type():
    # Test that the `sparse_output` parameter of RandomTreesEmbedding
    # works by returning a dense array.

    # Create the RTE with sparse=False
    hasher = RandomTreesEmbedding(n_estimators=10, sparse_output=False)
    X, y = datasets.make_circles(factor=0.5)
    X_transformed = hasher.fit_transform(X)

    # Assert that type is ndarray, not scipy.sparse.csr.csr_matrix
    assert_equal(type(X_transformed), np.ndarray)

def build_datasets(n_samples=100):
    X, y = make_classification(n_samples=n_samples, n_features=2, n_redundant=0, n_informative=2, n_clusters_per_class=1)
    X += 2 * np.random.uniform(size=X.shape)
    linearly_separable = (X, y)

    names = ['moons', 'circles', 'linear', 'xor']
    datasets = [make_moons(n_samples=n_samples, noise=0.3),
                make_circles(n_samples=n_samples, noise=0.2, factor=0.5),
                linearly_separable,
                xor_scale_invariant(n_samples=n_samples)]
    return (names, datasets)