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Python covariance.GraphLassoCV类代码示例

本文整理汇总了Python中sklearn.covariance.GraphLassoCV的典型用法代码示例。如果您正苦于以下问题:Python GraphLassoCV类的具体用法?Python GraphLassoCV怎么用?Python GraphLassoCV使用的例子?那么, 这里精选的类代码示例或许可以为您提供帮助。


在下文中一共展示了GraphLassoCV类的15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: calculate_connectivity_matrix

def calculate_connectivity_matrix(in_data, extraction_method):
    '''
    after extract_parcellation_time_series() connectivity matrices are calculated via specified extraction method

    returns np.array with matrixand saves this array also to matrix_file
    '''

    # fixme implement sparse inv covar
    import os, pickle
    import numpy as np

    if extraction_method == 'correlation':
        correlation_matrix = np.corrcoef(in_data.T)
        matrix = {'correlation': correlation_matrix}

    elif extraction_method == 'sparse_inverse_covariance':
        # Compute the sparse inverse covariance
        from sklearn.covariance import GraphLassoCV
        estimator = GraphLassoCV()
        estimator.fit(in_data)
        matrix = {'covariance': estimator.covariance_,
                  'sparse_inverse_covariance': estimator.precision_}

    else:
        raise (Exception('Unknown extraction method: %s' % extraction_method))

    matrix_file = os.path.join(os.getcwd(), 'matrix.pkl')
    with open(matrix_file, 'w') as f:
        pickle.dump(matrix, f)

    return matrix, matrix_file
开发者ID:fliem,项目名称:LeiCA_LIFE,代码行数:31,代码来源:utils.py

示例2: run_clustering

def run_clustering(methods, cases):
    true_method_groups = [m[1] for m in methods]
    edge_model = GraphLassoCV(alphas=4, n_refinements=5, n_jobs=3, max_iter=100)
    edge_model.fit(cases)
    CV = edge_model.covariance_
    
    num_clusters=3
    spectral = SpectralClustering(n_clusters=num_clusters,affinity='precomputed') 
    spectral.fit(np.asarray(CV))
    spec_sort=np.argsort(spectral.labels_)
    
    for i,m in enumerate(methods):
        print "%s:%d\t%s"%(m[1],spectral.labels_[i],m[0])
    print "Adj. Rand Score: %f"%adjusted_rand_score(spectral.labels_,true_method_groups)
开发者ID:IDEALLab,项目名称:design_method_recommendation_JMD_2014,代码行数:14,代码来源:paper_experiments.py

示例3: main

def main():
    sample, genes, raw_expression, cov = load_data()
    expression = raw_expression[raw_expression.min(1) > 100]
    expression_indices = numpy.nonzero(raw_expression.sum(1) > 6)[0].tolist()
    
    ## reorder and filter data
    #rep1_cols = numpy.array((3,0,5)) # 8 is co culture
    #rep2_cols = numpy.array((4,2,7)) # 9 is MRC5
    expression = expression[:,(3,4,0,2,5,7)]

    # log data
    expression = numpy.log10(expression + 1)[1:100,]
    cov = expression.dot(expression.T)
    print cov.shape
    #mo = GraphLasso(alpha=95, mode='lars', verbose=True) #, cv=KFold(3,2), n_jobs=24)
    mo = GraphLassoCV(mode='lars', verbose=True, cv=KFold(3,2), n_jobs=24)
    sparse_cov = mo.fit(cov)
    print( numpy.nonzero(sparse_cov)[0].sum() )
    return
开发者ID:nboley,项目名称:machinelearningexperiments,代码行数:19,代码来源:test_sparse_inv_cov.py

示例4: computePartialCorrelationsCV

def computePartialCorrelationsCV(coupling_data):

    # standardize
    coupling_data -= coupling_data.mean(axis=0)
    coupling_data /= coupling_data.std(axis=0)


    estimator = GraphLassoCV(alphas=10)
    estimator.fit(coupling_data)
    prec = estimator.get_precision()
    reg_alpha = estimator.alpha_


    #### partial correlations: rho_ij = - p_ij/ sqrt(p_ii * p_jj)
    #diagonal of precision matrix
    prec_diag = np.diag(prec)
    partial_correlations = -prec / np.sqrt(np.outer(prec_diag, prec_diag))

    # set lower half to zero
    partial_correlations[np.tril_indices(400)] = 0

    return estimator.get_precision(), partial_correlations, reg_alpha
开发者ID:susannvorberg,项目名称:contact_prediction,代码行数:22,代码来源:plot_inverse_covariance_analysis.py

示例5: mgsparse

def mgsparse(matrix, dimred=0, cutoff=1, eigtype = 'b'):
    ''' Plot ROC curve for using sparse covariance and precision matrix for multivariate gaussian classifier
    Input:
            matrix = n-by-m pandas data frame, each row is one bacteria strain, each column is one subject
            dimred = reduce dimensionality of covariance and inverse of covariance to n < len(x) if n is specified specified, 
            else no reduction in dimensions  
            cutoff = cutoff to top eigenvalues if specified, maybe less than n
            eigtype = pick n random(r), biggest(b) or smallest(s) eigenvalues to construct matrix B, default is biggest(b)
    Output:
            auc = area under ROC curve
    '''
    
    # convert matrix from Pandas data frame to array
    m = matrix.values
    
    # control and CD subjects
    con = (m.T[252:])
    cd = (m.T[:252])
    
    # get mean for each strain 
    conmean = vmean(con.T)
    cdmean = vmean(cd.T)
    
    
    # sparse covariance and precision matrix for control

    conglasso = GraphLassoCV()
    conglasso.fit(con)

    concov = conglasso.covariance_
    concovinv = conglasso.precision_

    # covariance and precision matrix for CD 

    cdglasso = GraphLassoCV()
    cdglasso.fit(cd)

    cdcov = cdglasso.covariance_
    cdcovinv = cdglasso.precision_
    
    
    listac = ndgaussianfitsparse(c24g, c24gmean, sc24gcov, sc24gcovinv, dimred = r)
    listbc = ndgaussianfitsparse(c24g, cd24gmean, scd24gcov, scd24gcovinv, dimred = r)
    listacd = ndgaussianfitsparse(cd24g, c24gmean, sc24gcov, sc24gcovinv, dimred= r)
    listbcd = ndgaussianfitsparse(cd24g, cd24gmean, scd24gcov, scd24gcovinv, dimred= r)
    auc = ndaucsklearn(listac, listbc, listacd, listbcd,  252, 172, tol = 2)
    
    return auc
开发者ID:Santhosh97,项目名称:Classification-Tests-on-Gut-Microbiome-Composition-Data,代码行数:48,代码来源:Microbiome.py

示例6: GroupSparseCovarianceCV

# Run group-sparse covariance on all subjects
from nilearn.group_sparse_covariance import GroupSparseCovarianceCV
gsc = GroupSparseCovarianceCV(max_iter=50, verbose=1)
gsc.fit(subjects)

for n in range(n_displayed):
    plt.subplot(n_displayed, 4, 4 * n + 2)
    plot_matrix(gsc.precisions_[..., n])
    if n == 0:
        plt.title("group-sparse\n$\\alpha=%.2f$" % gsc.alpha_)


# Fit one graph lasso per subject
from sklearn.covariance import GraphLassoCV
gl = GraphLassoCV(verbose=1)

for n, subject in enumerate(subjects[:n_displayed]):
    gl.fit(subject)

    plt.subplot(n_displayed, 4, 4 * n + 3)
    plot_matrix(gl.precision_)
    if n == 0:
        plt.title("graph lasso")
    plt.ylabel("$\\alpha=%.2f$" % gl.alpha_)


# Fit one graph lasso for all subjects at once
import numpy as np
gl.fit(np.concatenate(subjects))
开发者ID:DavidDJChen,项目名称:nilearn,代码行数:29,代码来源:plot_simulated_connectome.py

示例7: NiftiMapsMasker

    nmm = NiftiMapsMasker(
        mask_img=mask_file, maps_img=icas_path, resampling_target='mask',
        standardize=True, detrend=True)
    nmm.fit()
    nmm.maps_img_.to_filename('dbg_ica_maps.nii.gz')

    FS_netproj = nmm.transform(all_sub_rs_maps)
    np.save('%i_nets_timeseries' % sub_id, FS_netproj)

    # compute network sparse inverse covariance
    from sklearn.covariance import GraphLassoCV
    from nilearn.image import index_img
    from nilearn import plotting

    try:
        gsc_nets = GraphLassoCV(verbose=2, alphas=20)
        gsc_nets.fit(FS_netproj)

        np.save('%i_nets_cov' % sub_id, gsc_nets.covariance_)
        np.save('%i_nets_prec' % sub_id, gsc_nets.precision_)
    except:
        pass

    ###############################################################################
    # dump region poolings
    ###############################################################################
    from nilearn.image import resample_img

    crad = ds.fetch_atlas_craddock_2012()
    # atlas_nii = index_img(crad['scorr_mean'], 19)  # Craddock 200 region atlas
    atlas_nii = index_img(crad['scorr_mean'], 9)  # Craddock 100 region atlas
开发者ID:banilo,项目名称:prni2016,代码行数:31,代码来源:extract.py

示例8: scale

# -*- coding: utf-8 -*-
"""
Created on Mon Sep 12 10:16:16 2016

@author: jonyoung
"""

import connectivity_utils as utils
import numpy as np
import scipy.linalg as la
from sklearn.covariance import GraphLassoCV, ledoit_wolf, GraphLasso
from sklearn.preprocessing import scale


connectivity_data = utils.load_hcp_matrix('/home/jonyoung/IoP_data/Data/HCP_PTN820/node_timeseries/3T_HCP820_MSMAll_d15_ts2/715950.txt');

print connectivity_data
print np.shape(connectivity_data)
print np.std(connectivity_data, axis = 1)
connectivity_data = connectivity_data[:, :250]
X = scale(connectivity_data, axis=1)
model = GraphLassoCV(max_iter=1500, assume_centered=True)
model.fit(np.transpose(X))
开发者ID:jmyoung36,项目名称:basic_connectivity,代码行数:23,代码来源:test_hcp_timecourse_data.py

示例9: print

timeseries = spheres_masker.fit_transform(fmri_filename, confounds=confounds_filename)

###############################################################################
# Estimate correlations
# ---------------------
#
# All starts with the estimation of the signals **covariance** matrix. Here the
# number of ROIs exceeds the number of samples,
print("time series has {0} samples".format(timeseries.shape[0]))

###############################################################################
# in which situation the graphical lasso **sparse inverse covariance**
# estimator captures well the covariance **structure**.
from sklearn.covariance import GraphLassoCV

covariance_estimator = GraphLassoCV(verbose=1)

###############################################################################
# We just fit our regions signals into the `GraphLassoCV` object
covariance_estimator.fit(timeseries)

###############################################################################
# and get the ROI-to-ROI covariance matrix.
matrix = covariance_estimator.covariance_
print("Covariance matrix has shape {0}.".format(matrix.shape))

###############################################################################
# Plot matrix and graph
# ---------------------
#
# We use `matplotlib` plotting functions to visualize our correlation matrix
开发者ID:Neurita,项目名称:nilearn,代码行数:31,代码来源:plot_sphere_based_connectome.py

示例10: NiftiMapsMasker

##############################################################################
# Extract time series
# --------------------
from nilearn.input_data import NiftiMapsMasker
masker = NiftiMapsMasker(maps_img=atlas_filename, standardize=True,
                         memory='nilearn_cache', verbose=5)

time_series = masker.fit_transform(data.func[0],
                                   confounds=data.confounds)

##############################################################################
# Compute the sparse inverse covariance
# --------------------------------------
from sklearn.covariance import GraphLassoCV
estimator = GraphLassoCV()

estimator.fit(time_series)

##############################################################################
# Display the connectome matrix
# ------------------------------
from matplotlib import pyplot as plt

# Display the covariance
plt.figure(figsize=(10, 10))

# The covariance can be found at estimator.covariance_
plt.imshow(estimator.covariance_, interpolation="nearest",
           vmax=1, vmin=-1, cmap=plt.cm.RdBu_r)
# And display the labels
开发者ID:dillonplunkett,项目名称:nilearn,代码行数:30,代码来源:plot_inverse_covariance_connectome.py

示例11: datetime

    symbols, names = np.array(list(STOCKS.items())).T
   
    start = datetime(2014, 1, 1, 0, 0, 0, 0, pytz.utc)
    end = datetime(2016, 1, 1, 0, 0, 0, 0, pytz.utc)    

    quotes = [quotes_historical_yahoo(symbol, start, end, asobject=True) for symbol in symbols]

    qopen = np.array([q.open for q in quotes]).astype(np.float)
    qclose = np.array([q.close for q in quotes]).astype(np.float)                
            
    variation= qclose - qopen  #per day variation in price for each symbol
    X = variation.T
    X /= X.std(axis=0) #standardize to use correlations rather than covariance
                
    #estimate inverse covariance    
    graph = GraphLassoCV()
    graph.fit(X)
    
    gl_cov = graph.covariance_
    gl_prec = graph.precision_
    gl_alphas =graph.cv_alphas_
    gl_scores = np.mean(graph.grid_scores, axis=1)

    plt.figure()        
    sns.heatmap(gl_prec)
    
    plt.figure()    
    plt.plot(gl_alphas, gl_scores, marker='o', color='b', lw=2.0, label='GraphLassoCV')
    plt.title("Graph Lasso Alpha Selection")
    plt.xlabel("alpha")
    plt.ylabel("score")
开发者ID:vsmolyakov,项目名称:fin,代码行数:31,代码来源:inv_cov.py

示例12: GraphicLasso

def GraphicLasso(X):
    model = GraphLassoCV()
    model.fit(X)
    cov_ = model.covariance_
    prec_ = model.precision_
    return prec_
开发者ID:yfamy123,项目名称:BrainNet,代码行数:6,代码来源:GroupGraphic.py

示例13: empirical_covariance

    c0.append(temp_A[0])
    c1.append(temp_A[1])
    c2.append(temp_B)

data = np.array([c0, c1, c2])

data = data.transpose()

print data

# emp_cov = empirical_covariance(data, assume_centered=False)
#
# print emp_cov

model = GraphLassoCV()
model.fit(data)

cov_ = model.covariance_

prec_ = model.precision_

corr = np.corrcoef(data, rowvar=False)

print corr

# print cov_
# print prec_


threshold = 0.1
开发者ID:shangxing2015,项目名称:DQN,代码行数:30,代码来源:env_cov.py

示例14: get_EFA_HCA

EFA=True
survey_HCA = get_EFA_HCA(all_results['survey'], EFA)
survey_order = survey_HCA['reorder_vec']
task_HCA = get_EFA_HCA(all_results['task'], EFA)
task_order = task_HCA['reorder_vec']


all_data = pd.concat([all_results['task'].data.iloc[:, task_order], 
                      all_results['survey'].data.iloc[:, survey_order]], 
                    axis=1)
out, tuning = qgraph_cor(all_data, glasso=True, gamma=.5)

# recreate with sklearn just to check
data = scale(all_data)
clf = GraphLassoCV()
clf.fit(data)

sklearn_covariance = clf.covariance_[np.tril_indices_from(clf.covariance_)]
qgraph_covariance = out.values[np.tril_indices_from(out)]
method_correlation = np.corrcoef(sklearn_covariance, qgraph_covariance)[0,1]
assert method_correlation > .99

def add_attributes(g):
    g.vs['measurement'] = ['task']*len(task_order) + ['survey']*len(survey_order)
    task_clusters = task_HCA['labels'][task_order]
    survey_clusters = survey_HCA['labels'][survey_order] + max(task_clusters)
    g.vs['cluster'] = np.append(task_clusters, survey_clusters)
    
save_loc = path.join(path.dirname(all_results['task'].get_output_dir()), 
                     'graph_results')
开发者ID:IanEisenberg,项目名称:Self_Regulation_Ontology,代码行数:30,代码来源:gephi_graph_plot.py

示例15: GraphLassoCV

                              random_state=prng)
cov = linalg.inv(prec)
d = np.sqrt(np.diag(cov))
cov /= d
cov /= d[:, np.newaxis]
prec *= d
prec *= d[:, np.newaxis]
X = prng.multivariate_normal(np.zeros(n_features), cov, size=n_samples)
X -= X.mean(axis=0)
X /= X.std(axis=0)

##############################################################################
# Estimate the covariance
emp_cov = np.dot(X.T, X) / n_samples

model = GraphLassoCV()
model.fit(X)
cov_ = model.covariance_
prec_ = model.precision_

lw_cov_, _ = ledoit_wolf(X)
lw_prec_ = linalg.inv(lw_cov_)

##############################################################################
# Plot the results
pl.figure(figsize=(10, 6))
pl.subplots_adjust(left=0.02, right=0.98)

# plot the covariances
covs = [('Empirical', emp_cov), ('Ledoit-Wolf', lw_cov_),
        ('GraphLasso', cov_), ('True', cov)]
开发者ID:TPNguyen,项目名称:bigdata,代码行数:31,代码来源:plot_sparse_cov.py


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