Beispiel #1
0
def test_brain_data(tmpdir):

    # Add 3mm to list to test that resolution as well
    for resolution in ['2mm']:

        MNI_Template["resolution"] = resolution

        sim = Simulator()
        r = 10
        sigma = 1
        y = [0, 1]
        n_reps = 3
        output_dir = str(tmpdir)
        dat = sim.create_data(y, sigma, reps=n_reps, output_dir=output_dir)

        if MNI_Template["resolution"] == '2mm':
            shape_3d = (91, 109, 91)
            shape_2d = (6, 238955)
        elif MNI_Template["resolution"] == '3mm':
            shape_3d = (60, 72, 60)
            shape_2d = (6, 71020)

        y = pd.read_csv(os.path.join(str(tmpdir.join('y.csv'))),header=None, index_col=None)
        holdout = pd.read_csv(os.path.join(str(tmpdir.join('rep_id.csv'))),header=None,index_col=None)

        # Test load list of 4D images
        file_list = [str(tmpdir.join('data.nii.gz')), str(tmpdir.join('data.nii.gz'))]
        dat = Brain_Data(file_list)
        dat = Brain_Data([nb.load(x) for x in file_list])

        # Test load list
        dat = Brain_Data(data=str(tmpdir.join('data.nii.gz')), Y=y)

        # Test concatenate
        out = Brain_Data([x for x in dat])
        assert isinstance(out, Brain_Data)
        assert len(out)==len(dat)

        # Test to_nifti
        d = dat.to_nifti()
        assert d.shape[0:3] == shape_3d

        # Test load nibabel
        assert Brain_Data(d)

        # Test shape
        assert dat.shape() == shape_2d

        # Test Mean
        assert dat.mean().shape()[0] == shape_2d[1]

        # Test Std
        assert dat.std().shape()[0] == shape_2d[1]

        # Test add
        new = dat + dat
        assert new.shape() == shape_2d

        # Test subtract
        new = dat - dat
        assert new.shape() == shape_2d

        # Test multiply
        new = dat * dat
        assert new.shape() == shape_2d

        # Test Indexing
        index = [0, 3, 1]
        assert len(dat[index]) == len(index)
        index = range(4)
        assert len(dat[index]) == len(index)
        index = dat.Y == 1

        assert len(dat[index.values.flatten()]) == index.values.sum()

        assert len(dat[index]) == index.values.sum()
        assert len(dat[:3]) == 3

        # Test Iterator
        x = [x for x in dat]
        assert len(x) == len(dat)
        assert len(x[0].data.shape) == 1

        # # Test T-test
        out = dat.ttest()
        assert out['t'].shape()[0] == shape_2d[1]

        # # # Test T-test - permutation method
        # out = dat.ttest(threshold_dict={'permutation':'tfce','n_permutations':50,'n_jobs':1})
        # assert out['t'].shape()[0]==shape_2d[1]

        # Test Regress
        dat.X = pd.DataFrame({'Intercept':np.ones(len(dat.Y)),
                            'X1':np.array(dat.Y).flatten()}, index=None)

        # Standard OLS
        out = dat.regress()

        assert type(out['beta'].data) == np.ndarray
        assert type(out['t'].data) == np.ndarray
        assert type(out['p'].data) == np.ndarray
        assert type(out['residual'].data) == np.ndarray
        assert type(out['df'].data) == np.ndarray
        assert out['beta'].shape() == (2, shape_2d[1])
        assert out['t'][1].shape()[0] == shape_2d[1]

        # Robust OLS
        out = dat.regress(mode='robust')

        assert type(out['beta'].data) == np.ndarray
        assert type(out['t'].data) == np.ndarray
        assert type(out['p'].data) == np.ndarray
        assert type(out['residual'].data) == np.ndarray
        assert type(out['df'].data) == np.ndarray
        assert out['beta'].shape() == (2, shape_2d[1])
        assert out['t'][1].shape()[0] == shape_2d[1]

        # Test threshold
        i=1
        tt = threshold(out['t'][i], out['p'][i], .05)
        assert isinstance(tt, Brain_Data)

        # Test write
        dat.write(os.path.join(str(tmpdir.join('test_write.nii'))))
        assert Brain_Data(os.path.join(str(tmpdir.join('test_write.nii'))))

        # Test append
        assert dat.append(dat).shape()[0] == shape_2d[0]*2

        # Test distance
        distance = dat.distance(method='euclidean')
        assert isinstance(distance, Adjacency)
        assert distance.square_shape()[0] == shape_2d[0]

        # Test predict
        stats = dat.predict(algorithm='svm',
                            cv_dict={'type': 'kfolds', 'n_folds': 2},
                            plot=False, **{'kernel':"linear"})

        # Support Vector Regression, with 5 fold cross-validation with Platt Scaling
        # This will output probabilities of each class
        stats = dat.predict(algorithm='svm',
                            cv_dict=None, plot=False,
                            **{'kernel':'linear', 'probability':True})
        assert isinstance(stats['weight_map'], Brain_Data)

        # Logistic classificiation, with 2 fold cross-validation.
        stats = dat.predict(algorithm='logistic',
                            cv_dict={'type': 'kfolds', 'n_folds': 2},
                            plot=False)
        assert isinstance(stats['weight_map'], Brain_Data)

        # Ridge classificiation,
        stats = dat.predict(algorithm='ridgeClassifier', cv_dict=None, plot=False)
        assert isinstance(stats['weight_map'], Brain_Data)

        # Ridge
        stats = dat.predict(algorithm='ridge',
                            cv_dict={'type': 'kfolds', 'n_folds': 2,
                            'subject_id':holdout}, plot=False, **{'alpha':.1})

        # Lasso
        stats = dat.predict(algorithm='lasso',
                            cv_dict={'type': 'kfolds', 'n_folds': 2,
                            'stratified':dat.Y}, plot=False, **{'alpha':.1})

        # PCR
        stats = dat.predict(algorithm='pcr', cv_dict=None, plot=False)

        # Test Similarity
        r = dat.similarity(stats['weight_map'])
        assert len(r) == shape_2d[0]
        r2 = dat.similarity(stats['weight_map'].to_nifti())
        assert len(r2) == shape_2d[0]
        r = dat.similarity(stats['weight_map'], method='dot_product')
        assert len(r) == shape_2d[0]
        r = dat.similarity(stats['weight_map'], method='cosine')
        assert len(r) == shape_2d[0]
        r = dat.similarity(dat, method='correlation')
        assert r.shape == (dat.shape()[0],dat.shape()[0])
        r = dat.similarity(dat, method='dot_product')
        assert r.shape == (dat.shape()[0],dat.shape()[0])
        r = dat.similarity(dat, method='cosine')
        assert r.shape == (dat.shape()[0],dat.shape()[0])

        # Test apply_mask - might move part of this to test mask suite
        s1 = create_sphere([12, 10, -8], radius=10)
        assert isinstance(s1, nb.Nifti1Image)
        masked_dat = dat.apply_mask(s1)
        assert masked_dat.shape()[1] == np.sum(s1.get_data() != 0)

        # Test extract_roi
        mask = create_sphere([12, 10, -8], radius=10)
        assert len(dat.extract_roi(mask)) == shape_2d[0]

        # Test r_to_z
        z = dat.r_to_z()
        assert z.shape() == dat.shape()

        # Test copy
        d_copy = dat.copy()
        assert d_copy.shape() == dat.shape()

        # Test detrend
        detrend = dat.detrend()
        assert detrend.shape() == dat.shape()

        # Test standardize
        s = dat.standardize()
        assert s.shape() == dat.shape()
        assert np.isclose(np.sum(s.mean().data), 0, atol=.1)
        s = dat.standardize(method='zscore')
        assert s.shape() == dat.shape()
        assert np.isclose(np.sum(s.mean().data), 0, atol=.1)

        # Test Sum
        s = dat.sum()
        assert s.shape() == dat[1].shape()

        # Test Groupby
        s1 = create_sphere([12, 10, -8], radius=10)
        s2 = create_sphere([22, -2, -22], radius=10)
        mask = Brain_Data([s1, s2])
        d = dat.groupby(mask)
        assert isinstance(d, Groupby)

        # Test Aggregate
        mn = dat.aggregate(mask, 'mean')
        assert isinstance(mn, Brain_Data)
        assert len(mn.shape()) == 1

        # Test Threshold
        s1 = create_sphere([12, 10, -8], radius=10)
        s2 = create_sphere([22, -2, -22], radius=10)
        mask = Brain_Data(s1)*5
        mask = mask + Brain_Data(s2)

        m1 = mask.threshold(upper=.5)
        m2 = mask.threshold(upper=3)
        m3 = mask.threshold(upper='98%')
        m4 = Brain_Data(s1)*5 + Brain_Data(s2)*-.5
        m4 = mask.threshold(upper=.5,lower=-.3)
        assert np.sum(m1.data > 0) > np.sum(m2.data > 0)
        assert np.sum(m1.data > 0) == np.sum(m3.data > 0)
        assert np.sum(m4.data[(m4.data > -.3) & (m4.data <.5)]) == 0
        assert np.sum(m4.data[(m4.data < -.3) | (m4.data >.5)]) > 0

        # Test Regions
        r = mask.regions(min_region_size=10)
        m1 = Brain_Data(s1)
        m2 = r.threshold(1, binarize=True)
        # assert len(r)==2
        assert len(np.unique(r.to_nifti().get_data())) == 2
        diff = m2-m1
        assert np.sum(diff.data) == 0

        # Test Bootstrap
        masked = dat.apply_mask(create_sphere(radius=10, coordinates=[0, 0, 0]))
        n_samples = 3
        b = masked.bootstrap('mean', n_samples=n_samples)
        assert isinstance(b['Z'], Brain_Data)
        b = masked.bootstrap('std', n_samples=n_samples)
        assert isinstance(b['Z'], Brain_Data)
        b = masked.bootstrap('predict', n_samples=n_samples, plot=False)
        assert isinstance(b['Z'], Brain_Data)
        b = masked.bootstrap('predict', n_samples=n_samples,
                        plot=False, cv_dict={'type':'kfolds','n_folds':3})
        assert isinstance(b['Z'], Brain_Data)
        b = masked.bootstrap('predict', n_samples=n_samples,
                        save_weights=True, plot=False)
        assert len(b['samples'])==n_samples

        # Test decompose
        n_components = 3
        stats = dat.decompose(algorithm='pca', axis='voxels',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        stats = dat.decompose(algorithm='ica', axis='voxels',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        dat.data = dat.data + 2
        dat.data[dat.data<0] = 0
        stats = dat.decompose(algorithm='nnmf', axis='voxels',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        stats = dat.decompose(algorithm='fa', axis='voxels',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        stats = dat.decompose(algorithm='pca', axis='images',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        stats = dat.decompose(algorithm='ica', axis='images',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        dat.data = dat.data + 2
        dat.data[dat.data<0] = 0
        stats = dat.decompose(algorithm='nnmf', axis='images',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        stats = dat.decompose(algorithm='fa', axis='images',
                              n_components=n_components)
        assert n_components == len(stats['components'])
        assert stats['weights'].shape == (len(dat), n_components)

        # Test Hyperalignment Method
        sim = Simulator()
        y = [0, 1]
        n_reps = 10
        s1 = create_sphere([0, 0, 0], radius=3)
        d1 = sim.create_data(y, 1, reps=n_reps, output_dir=None).apply_mask(s1)
        d2 = sim.create_data(y, 2, reps=n_reps, output_dir=None).apply_mask(s1)
        d3 = sim.create_data(y, 3, reps=n_reps, output_dir=None).apply_mask(s1)

        # Test procrustes using align
        data = [d1, d2, d3]
        out = align(data, method='procrustes')
        assert len(data) == len(out['transformed'])
        assert len(data) == len(out['transformation_matrix'])
        assert data[0].shape() == out['common_model'].shape()
        transformed = np.dot(d1.data, out['transformation_matrix'][0])
        centered = d1.data - np.mean(d1.data, 0)
        transformed = (np.dot(centered/np.linalg.norm(centered), out['transformation_matrix'][0])*out['scale'][0])
        np.testing.assert_almost_equal(0, np.sum(out['transformed'][0].data - transformed), decimal=5)

        # Test deterministic brain_data
        bout = d1.align(out['common_model'], method='deterministic_srm')
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[1] == bout['transformation_matrix'].shape[0]
        btransformed = np.dot(d1.data, bout['transformation_matrix'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data - btransformed))

        # Test deterministic brain_data
        bout = d1.align(out['common_model'], method='probabilistic_srm')
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[1] == bout['transformation_matrix'].shape[0]
        btransformed = np.dot(d1.data, bout['transformation_matrix'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data-btransformed))

        # Test procrustes brain_data
        bout = d1.align(out['common_model'], method='procrustes')
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[1] == bout['transformation_matrix'].shape[0]
        centered = d1.data - np.mean(d1.data, 0)
        btransformed = (np.dot(centered/np.linalg.norm(centered), bout['transformation_matrix'])*bout['scale'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data-btransformed), decimal=5)
        np.testing.assert_almost_equal(0, np.sum(out['transformed'][0].data - bout['transformed'].data))

        # Test hyperalignment on Brain_Data over time (axis=1)
        sim = Simulator()
        y = [0, 1]
        n_reps = 10
        s1 = create_sphere([0, 0, 0], radius=5)
        d1 = sim.create_data(y, 1, reps=n_reps, output_dir=None).apply_mask(s1)
        d2 = sim.create_data(y, 2, reps=n_reps, output_dir=None).apply_mask(s1)
        d3 = sim.create_data(y, 3, reps=n_reps, output_dir=None).apply_mask(s1)
        data = [d1, d2, d3]

        out = align(data, method='procrustes', axis=1)
        assert len(data) == len(out['transformed'])
        assert len(data) == len(out['transformation_matrix'])
        assert data[0].shape() == out['common_model'].shape()
        centered = data[0].data.T-np.mean(data[0].data.T, 0)
        transformed = (np.dot(centered/np.linalg.norm(centered), out['transformation_matrix'][0])*out['scale'][0])
        np.testing.assert_almost_equal(0,np.sum(out['transformed'][0].data-transformed.T), decimal=5)

        bout = d1.align(out['common_model'], method='deterministic_srm', axis=1)
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[0] == bout['transformation_matrix'].shape[0]
        btransformed = np.dot(d1.data.T, bout['transformation_matrix'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data-btransformed.T))

        bout = d1.align(out['common_model'], method='probabilistic_srm', axis=1)
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[0] == bout['transformation_matrix'].shape[0]
        btransformed = np.dot(d1.data.T, bout['transformation_matrix'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data-btransformed.T))

        bout = d1.align(out['common_model'], method='procrustes', axis=1)
        assert d1.shape() == bout['transformed'].shape()
        assert d1.shape() == bout['common_model'].shape()
        assert d1.shape()[0] == bout['transformation_matrix'].shape[0]
        centered = d1.data.T-np.mean(d1.data.T, 0)
        btransformed = (np.dot(centered/np.linalg.norm(centered), bout['transformation_matrix'])*bout['scale'])
        np.testing.assert_almost_equal(0, np.sum(bout['transformed'].data-btransformed.T), decimal=5)
        np.testing.assert_almost_equal(0, np.sum(out['transformed'][0].data-bout['transformed'].data))
Beispiel #2
0
def test_data(tmpdir):
    sim = Simulator()
    r = 10
    sigma = 1
    y = [0, 1]
    n_reps = 3
    output_dir = str(tmpdir)
    sim.create_data(y, sigma, reps=n_reps, output_dir=output_dir)

    shape_3d = (91, 109, 91)
    shape_2d = (6, 238955)
    y = pd.read_csv(os.path.join(str(tmpdir.join('y.csv'))),
                    header=None,
                    index_col=None).T
    flist = glob.glob(str(tmpdir.join('centered*.nii.gz')))

    # Test load list
    dat = Brain_Data(data=flist, Y=y)

    # Test load file
    assert Brain_Data(flist[0])

    # Test to_nifti
    d = dat.to_nifti()
    assert d.shape[0:3] == shape_3d

    # Test load nibabel
    assert Brain_Data(d)

    # Test shape
    assert dat.shape() == shape_2d

    # Test Mean
    assert dat.mean().shape()[0] == shape_2d[1]

    # Test Std
    assert dat.std().shape()[0] == shape_2d[1]

    # Test add
    new = dat + dat
    assert new.shape() == shape_2d

    # Test subtract
    new = dat - dat
    assert new.shape() == shape_2d

    # Test multiply
    new = dat * dat
    assert new.shape() == shape_2d

    # Test Iterator
    x = [x for x in dat]
    assert len(x) == len(dat)
    assert len(x[0].data.shape) == 1

    # # Test T-test
    out = dat.ttest()
    assert out['t'].shape()[0] == shape_2d[1]

    # # # Test T-test - permutation method
    # out = dat.ttest(threshold_dict={'permutation':'tfce','n_permutations':50,'n_jobs':1})
    # assert out['t'].shape()[0]==shape_2d[1]

    # Test Regress
    dat.X = pd.DataFrame(
        {
            'Intercept': np.ones(len(dat.Y)),
            'X1': np.array(dat.Y).flatten()
        },
        index=None)
    out = dat.regress()
    assert out['beta'].shape() == (2, shape_2d[1])

    # Test indexing
    assert out['t'][1].shape()[0] == shape_2d[1]

    # Test threshold
    i = 1
    tt = threshold(out['t'][i], out['p'][i], .05)
    assert isinstance(tt, Brain_Data)

    # Test write
    dat.write(os.path.join(str(tmpdir.join('test_write.nii'))))
    assert Brain_Data(os.path.join(str(tmpdir.join('test_write.nii'))))

    # Test append
    assert dat.append(dat).shape()[0] == shape_2d[0] * 2

    # Test distance
    distance = dat.distance(method='euclidean')
    assert distance.shape == (shape_2d[0], shape_2d[0])

    # Test predict
    stats = dat.predict(algorithm='svm',
                        cv_dict={
                            'type': 'kfolds',
                            'n_folds': 2,
                            'n': len(dat.Y)
                        },
                        plot=False,
                        **{'kernel': "linear"})

    # Support Vector Regression, with 5 fold cross-validation with Platt Scaling
    # This will output probabilities of each class
    stats = dat.predict(algorithm='svm',
                        cv_dict=None,
                        plot=False,
                        **{
                            'kernel': 'linear',
                            'probability': True
                        })

    assert isinstance(stats['weight_map'], Brain_Data)
    # Logistic classificiation, with 5 fold stratified cross-validation.

    stats = dat.predict(algorithm='logistic',
                        cv_dict={
                            'type': 'kfolds',
                            'n_folds': 5,
                            'n': len(dat.Y)
                        },
                        plot=False)
    assert isinstance(stats['weight_map'], Brain_Data)

    # Ridge classificiation, with 5 fold between-subject cross-validation, where data for each subject is held out together.
    stats = dat.predict(algorithm='ridgeClassifier', cv_dict=None, plot=False)
    assert isinstance(stats['weight_map'], Brain_Data)

    # Test Similarity
    r = dat.similarity(stats['weight_map'])
    assert len(r) == shape_2d[0]
    r2 = dat.similarity(stats['weight_map'].to_nifti())
    assert len(r2) == shape_2d[0]

    # Test apply_mask - might move part of this to test mask suite
    s1 = create_sphere([41, 64, 55], radius=10)
    assert isinstance(s1, nb.Nifti1Image)
    s2 = Brain_Data(s1)
    masked_dat = dat.apply_mask(s1)
    assert masked_dat.shape()[1] == np.sum(s2.data != 0)

    # Test extract_roi
    mask = create_sphere([41, 64, 55], radius=10)
    assert len(dat.extract_roi(mask)) == shape_2d[0]

    # Test r_to_z
    z = dat.r_to_z()
    assert z.shape() == dat.shape()

    # Test copy
    d_copy = dat.copy()
    assert d_copy.shape() == dat.shape()

    # Test detrend
    detrend = dat.detrend()
    assert detrend.shape() == dat.shape()
# simple model of pain intensity and an intercept.  This is just for illustration
# purposes as there are only 3 observations per subject.  We initialize an empty
# Brain_Data() instance and loop over all subjects running a univariate regression 
# separately for each participant.  We aggregate the beta estimates for pain intensity
# across subjects.

from nltools.data import Brain_Data
import numpy as np
import pandas as pd

all_sub = Brain_Data()
for s in subject_id.unique():
    sdat = data[np.where(metadata['SubjectID']==s)[0]]
    sdat.X = pd.DataFrame(data={'Intercept':np.ones(sdat.shape()[0]),'Pain':sdat.X['PainLevel']})
    stats = sdat.regress()
    all_sub = all_sub.append(stats['beta'][1])

#########################################################################
# We can now run a one-sample t-test at every voxel to test whether it is 
# significantly different from zero across participants.  We will threshold
# the results using FDR correction, q < 0.001.

t_stats = all_sub.ttest(threshold_dict={'fdr':.001})
t_stats['thr_t'].plot()

#########################################################################
# Run Linear Contrast
# -------------------
# 
# Obviously, the univariate regression isn't a great idea when there are only
# three observations per subject.  As we predict a monotonic increase in pain
# simple model of pain intensity and an intercept.  This is just for illustration
# purposes as there are only 3 observations per subject.  We initialize an empty
# Brain_Data() instance and loop over all subjects running a univariate regression 
# separately for each participant.  We aggregate the beta estimates for pain intensity
# across subjects.

from nltools.data import Brain_Data
import numpy as np
import pandas as pd

all_sub = Brain_Data()
for s in subject_id.unique():
    sdat = data[np.where(metadata['SubjectID']==s)[0]]
    sdat.X = pd.DataFrame(data={'Intercept':np.ones(sdat.shape()[0]),'Pain':sdat.X['PainLevel']})
    stats = sdat.regress()
    all_sub = all_sub.append(stats['beta'][1])

#########################################################################
# We can now run a one-sample t-test at every voxel to test whether it is 
# significantly different from zero across participants.  We will threshold
# the results using FDR correction, q < 0.001.

t_stats = all_sub.ttest(threshold_dict={'fdr':.001})
t_stats['thr_t'].plot()

#########################################################################
# Run Linear Contrast
# -------------------
# 
# Obviously, the univariate regression isn't a great idea when there are only
# three observations per subject.  As we predict a monotonic increase in pain
Beispiel #5
0
def test_brain_data(tmpdir):
    sim = Simulator()
    r = 10
    sigma = 1
    y = [0, 1]
    n_reps = 3
    output_dir = str(tmpdir)
    sim.create_data(y, sigma, reps=n_reps, output_dir=output_dir)

    shape_3d = (91, 109, 91)
    shape_2d = (6, 238955)
    y=pd.read_csv(os.path.join(str(tmpdir.join('y.csv'))), header=None,index_col=None).T
    holdout=pd.read_csv(os.path.join(str(tmpdir.join('rep_id.csv'))),header=None,index_col=None).T
    flist = glob.glob(str(tmpdir.join('centered*.nii.gz')))

    # Test load list
    dat = Brain_Data(data=flist,Y=y)

    # Test load file
    assert Brain_Data(flist[0])

    # Test to_nifti
    d = dat.to_nifti()
    assert d.shape[0:3] == shape_3d

    # Test load nibabel
    assert Brain_Data(d)

    # Test shape
    assert dat.shape() == shape_2d

    # Test Mean
    assert dat.mean().shape()[0] == shape_2d[1]

    # Test Std
    assert dat.std().shape()[0] == shape_2d[1]

    # Test add
    new = dat + dat
    assert new.shape() == shape_2d

    # Test subtract
    new = dat - dat
    assert new.shape() == shape_2d

    # Test multiply
    new = dat * dat
    assert new.shape() == shape_2d

    # Test Iterator
    x = [x for x in dat]
    assert len(x) == len(dat)
    assert len(x[0].data.shape) == 1

    # # Test T-test
    out = dat.ttest()
    assert out['t'].shape()[0] == shape_2d[1]

    # # # Test T-test - permutation method
    # out = dat.ttest(threshold_dict={'permutation':'tfce','n_permutations':50,'n_jobs':1})
    # assert out['t'].shape()[0]==shape_2d[1]

    # Test Regress
    dat.X = pd.DataFrame({'Intercept':np.ones(len(dat.Y)), 'X1':np.array(dat.Y).flatten()},index=None)
    out = dat.regress()
    assert out['beta'].shape() == (2,shape_2d[1])

    # Test indexing
    assert out['t'][1].shape()[0] == shape_2d[1]

    # Test threshold
    i=1
    tt = threshold(out['t'][i], out['p'][i], .05)
    assert isinstance(tt,Brain_Data)

    # Test write
    dat.write(os.path.join(str(tmpdir.join('test_write.nii'))))
    assert Brain_Data(os.path.join(str(tmpdir.join('test_write.nii'))))

    # Test append
    assert dat.append(dat).shape()[0]==shape_2d[0]*2

    # Test distance
    distance = dat.distance(method='euclidean')
    assert isinstance(distance,Adjacency)
    assert distance.square_shape()[0]==shape_2d[0]

    # Test predict
    stats = dat.predict(algorithm='svm', cv_dict={'type': 'kfolds','n_folds': 2}, plot=False,**{'kernel':"linear"})

    # Support Vector Regression, with 5 fold cross-validation with Platt Scaling
    # This will output probabilities of each class
    stats = dat.predict(algorithm='svm', cv_dict=None, plot=False,**{'kernel':'linear', 'probability':True})
    assert isinstance(stats['weight_map'],Brain_Data)

    # Logistic classificiation, with 2 fold cross-validation.
    stats = dat.predict(algorithm='logistic', cv_dict={'type': 'kfolds', 'n_folds': 2}, plot=False)
    assert isinstance(stats['weight_map'],Brain_Data)

    # Ridge classificiation,
    stats = dat.predict(algorithm='ridgeClassifier', cv_dict=None,plot=False)
    assert isinstance(stats['weight_map'],Brain_Data)

    # Ridge
    stats = dat.predict(algorithm='ridge', cv_dict={'type': 'kfolds', 'n_folds': 2,'subject_id':holdout}, plot=False,**{'alpha':.1})

    # Lasso
    stats = dat.predict(algorithm='lasso', cv_dict={'type': 'kfolds', 'n_folds': 2,'stratified':dat.Y}, plot=False,**{'alpha':.1})

    # PCR
    stats = dat.predict(algorithm='pcr', cv_dict=None, plot=False)

    # Test Similarity
    r = dat.similarity(stats['weight_map'])
    assert len(r) == shape_2d[0]
    r2 = dat.similarity(stats['weight_map'].to_nifti())
    assert len(r2) == shape_2d[0]

    # Test apply_mask - might move part of this to test mask suite
    s1 = create_sphere([12, 10, -8], radius=10)
    assert isinstance(s1, nb.Nifti1Image)
    s2 = Brain_Data(s1)
    masked_dat = dat.apply_mask(s1)
    assert masked_dat.shape()[1] == np.sum(s2.data != 0)

    # Test extract_roi
    mask = create_sphere([12, 10, -8], radius=10)
    assert len(dat.extract_roi(mask)) == shape_2d[0]

    # Test r_to_z
    z = dat.r_to_z()
    assert z.shape() == dat.shape()

    # Test copy
    d_copy = dat.copy()
    assert d_copy.shape() == dat.shape()

    # Test detrend
    detrend = dat.detrend()
    assert detrend.shape() == dat.shape()

    # Test standardize
    s = dat.standardize()
    assert s.shape() == dat.shape()
    assert np.isclose(np.sum(s.mean().data), 0, atol=.1)
    s = dat.standardize(method='zscore')
    assert s.shape() == dat.shape()
    assert np.isclose(np.sum(s.mean().data), 0, atol=.1)

    # Test Sum
    s = dat.sum()
    assert s.shape() == dat[1].shape()

    # Test Groupby
    s1 = create_sphere([12, 10, -8], radius=10)
    s2 = create_sphere([22, -2, -22], radius=10)
    mask = Brain_Data([s1, s2])
    d = dat.groupby(mask)
    assert isinstance(d, Groupby)

    # Test Aggregate
    mn = dat.aggregate(mask, 'mean')
    assert isinstance(mn, Brain_Data)
    assert len(mn.shape()) == 1

    # Test Threshold
    s1 = create_sphere([12, 10, -8], radius=10)
    s2 = create_sphere([22, -2, -22], radius=10)
    mask = Brain_Data(s1)*5
    mask = mask + Brain_Data(s2)

    m1 = mask.threshold(thresh=.5)
    m2 = mask.threshold(thresh=3)
    m3 = mask.threshold(thresh='98%')
    assert np.sum(m1.data > 0) > np.sum(m2.data > 0)
    assert np.sum(m1.data > 0) == np.sum(m3.data > 0)

    # Test Regions
    r = mask.regions(min_region_size=10)
    m1 = Brain_Data(s1)
    m2 = r.threshold(1, binarize=True)
    # assert len(r)==2
    assert len(np.unique(r.to_nifti().get_data())) == 2 # JC edit: I think this is what you were trying to do
    diff = m2-m1
    assert np.sum(diff.data) == 0
# In[2]:

left_file_list = glob.glob(
    os.path.join(data_dir, 'derivatives', 'fmriprep', '*', 'func',
                 '*_video_left*.nii.gz'))
left_file_list.sort()
left = Brain_Data(left_file_list)

right_file_list = glob.glob(
    os.path.join(data_dir, 'derivatives', 'fmriprep', '*', 'func',
                 '*_video_right*.nii.gz'))
right_file_list.sort()
right = Brain_Data(right_file_list)

data = left.append(right)

# Next, we need to create the labels or outcome variable to train the model. We will make a vector of ones and zeros to indicate left images and right images, respectively.
#
# We assign this vector to the `data.Y` attribute of the Brain_Data instance.

# In[3]:

Y = pd.DataFrame(
    np.hstack([np.ones(len(left_file_list)),
               np.zeros(len(left_file_list))]))

data.Y = Y

# okay, we are ready to go. Let's now train our first model. We will use a support vector machine (SVM) to learn a pattern that can discriminate left from right motor responses across all 9 participants.
Beispiel #7
0
    # create subject-level wholebrain (wb) masks (inclusive of all voxels in run-wise masks)
    #call("3dcalc -a masks[0] -b masks[1] -c masks[2] -d masks[3] -expr 'ispositive((a+b+c+d)-0)' "
    #   " -prefix {0}_brainmask.nii.gz".format(sub), shell=True)

    smoothed_fns = sorted(
        glob.glob(
            join(base_dir, 'derivatives', 'fmriprep', sub, ses, 'func',
                 '*_4mm.nii.gz')))
    wb_mask = join(base_dir, 'derivatives', 'fmriprep', sub, ses, 'func',
                   '{0}_brainmask.nii.gz').format(sub)

    alldat = Brain_Data()
    for fn in smoothed_fns:
        dat = Brain_Data(fn)
        alldat = alldat.append(dat)

    maskeddat = alldat.apply_mask(nib.load(wb_mask))
    mn = np.mean(maskeddat.data, axis=0)
    sd = np.std(maskeddat.data, axis=0)
    tsnr = np.true_divide(mn, sd)
    # Compute mean across voxels within each TR
    global_mn = np.mean(maskeddat.data, axis=1)
    global_sd = np.std(maskeddat.data, axis=1)
    # Unmask data for plotting below
    mn = unmask(mn, wb_mask)
    sd = unmask(sd, wb_mask)
    tsnr = unmask(tsnr, wb_mask)

    # Identify global signal outliers
    global_outliers = np.append(