def balance_dataset_timewise(ds, label, sort=True, **kwargs):
################ To be changed ######################
m_fixation = ds.targets == 'fixation'
ev_fix = zip(ds.chunks[m_fixation],
4 * ((ds.sa.events_number[m_fixation] + 2) / 4 - 1) + 2)
####################################################
ev_fix = np.array(ev_fix)
ds.sa.events_number[m_fixation] = np.int_(ev_fix.T[1])
arg_sort = np.argsort(ds.sa.events_number)
events = find_events(chunks=ds[arg_sort].sa.chunks,
targets=ds[arg_sort].sa.targets)
# min duration
min_duration = np.min([e['duration'] for e in events])
mask = False
for ev in np.unique(ds.sa.events_number):
mask_event = ds.sa.events_number == ev
mask_event[np.nonzero(mask_event)[0][min_duration - 1] + 1:] = False
mask = mask + mask_event
if sort == True:
arg_sort = np.argsort(ds[mask].sa.events_number)
ds = ds[mask][arg_sort]
else:
ds = ds[mask]
ds.a.events = find_events(targets=ds.targets, chunks=ds.chunks)
return ds
def balance_dataset_timewise(ds, label, sort=True, **kwargs):
################ To be changed ######################
m_fixation = ds.targets == 'fixation'
ev_fix = zip(ds.chunks[m_fixation],
4*((ds.sa.events_number[m_fixation]+2)/4 - 1 )+2)
####################################################
ev_fix=np.array(ev_fix)
ds.sa.events_number[m_fixation] = np.int_(ev_fix.T[1])
arg_sort = np.argsort(ds.sa.events_number)
events = find_events(chunks = ds[arg_sort].sa.chunks,
targets = ds[arg_sort].sa.targets)
# min duration
min_duration = np.min( [e['duration'] for e in events])
mask = False
for ev in np.unique(ds.sa.events_number):
mask_event = ds.sa.events_number == ev
mask_event[np.nonzero(mask_event)[0][min_duration-1]+1:] = False
mask = mask + mask_event
if sort == True:
arg_sort = np.argsort(ds[mask].sa.events_number)
ds = ds[mask][arg_sort]
else:
ds = ds[mask]
ds.a.events = find_events(targets = ds.targets, chunks = ds.chunks)
return ds
def find_events_dataset(ds, **kwargs):
ds.a.events = find_events(#event= ds.sa.event_num,
chunks = ds.sa.chunks,
targets = ds.sa.targets)
return ds
def load_spatiotemporal_dataset(ds, **kwargs):
onset = 0
for arg in kwargs:
if (arg == 'onset'):
onset = kwargs[arg]
if (arg == 'duration'):
duration = kwargs[arg]
if (arg == 'enable_results'):
enable_results = kwargs[arg]
events = find_events(targets = ds.sa.targets, chunks = ds.sa.chunks)
#task_events = [e for e in events if e['targets'] in ['Vipassana','Samatha']]
if 'duration' in locals():
events = [e for e in events if e['duration'] >= duration]
else:
duration = np.min([ev['duration'] for ev in events])
for e in events:
e['onset'] += onset
e['duration'] = duration
evds = eventrelated_dataset(ds, events = events)
return evds
def test_get_contrasts():
# preamble borrowed from the previous test
skip_if_no_external('nibabel')
skip_if_no_external('nipy') # ATM relies on NiPy's GLM implementation
# taking subset of the dataset to speed testing up
ds = load_example_fmri_dataset('25mm', literal=True)[{
'chunks': [0, 1]
}, :3]
# TODO: simulate short dataset with known properties and use it
# for testing
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
tr = ds.a.imghdr['pixdim'][4]
for ev in events:
for a in ('onset', 'duration'):
ev[a] = ev[a] * tr
evds = fit_event_hrf_model(
ds,
events=events,
time_attr='time_coords',
condition_attr='targets',
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
return_model=True,
)
# Simple one -- stat per each condition
cons = get_contrasts(evds)
# and let's get p-values
cons_p = get_contrasts(evds, fxname='p_value')
# Without contrasts explicitly prescribed -- there will be one per each
# condition
assert_array_equal(cons.UT, evds.UT)
# and per each feature
assert_equal(cons.shape, (len(evds.UT), evds.nfeatures))
assert_array_less(cons_p, 1)
assert_array_less(0, cons_p)
cons_fh = get_contrasts(
evds,
contrasts={
'face-house': {
'face': 1,
'house': -1
},
'betterface': {
'face': 1,
'house': -0.5,
'scrambledpix': -0.5
}
},
)
# print(cons_fh.samples)
assert_array_equal(cons_fh.UT, ['betterface', 'face-house'])
# and nipy does one tailed test so all p-values should correspond to z-s
skip_if_no_external('scipy')
import scipy.stats.distributions as ssd
assert_array_almost_equal(ssd.norm().isf(cons_p), cons)
def add_events(ds):
ev_list = []
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
for i in range(len(events)):
duration = events[i]['duration']
for _ in range(duration):
ev_list.append(i + 1)
ds.a['events'] = events # Update event field
ds.sa['events_number'] = ev_list # Update event number
return ds
def test_samples_attributes(self):
sa = SampleAttributes(pathjoin(pymvpa_dataroot,
'attributes_literal.txt'),
literallabels=True)
ok_(sa.nrows == 1452, msg='There should be 1452 samples')
# convert to event list, with some custom attr
ev = find_events(**sa)
ok_(len(ev) == 17 * (max(sa.chunks) + 1),
msg='Not all events got detected.')
ok_(ev[0]['targets'] == ev[-1]['targets'] == 'rest',
msg='First and last event are rest condition.')
ok_(ev[-1]['onset'] + ev[-1]['duration'] == sa.nrows,
msg='Something is wrong with the timiing of the events')
def test_samples_attributes(self):
sa = SampleAttributes(os.path.join(pymvpa_dataroot,
'attributes_literal.txt'),
literallabels=True)
ok_(sa.nrows == 1452, msg='There should be 1452 samples')
# convert to event list, with some custom attr
ev = find_events(**sa)
ok_(len(ev) == 17 * (max(sa.chunks) + 1),
msg='Not all events got detected.')
ok_(ev[0]['targets'] == ev[-1]['targets'] == 'rest',
msg='First and last event are rest condition.')
ok_(ev[-1]['onset'] + ev[-1]['duration'] == sa.nrows,
msg='Something is wrong with the timiing of the events')
def test_erdataset():
# 3 chunks, 5 targets, blocks of 5 samples each
nchunks = 3
ntargets = 5
blocklength = 5
nfeatures = 10
targets = np.tile(np.repeat(range(ntargets), blocklength), nchunks)
chunks = np.repeat(np.arange(nchunks), ntargets * blocklength)
samples = np.repeat(
np.arange(nchunks * ntargets * blocklength),
nfeatures).reshape(-1, nfeatures)
ds = dataset_wizard(samples, targets=targets, chunks=chunks)
# check if events are determined properly
evs = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
for ev in evs:
assert_equal(ev['duration'], blocklength)
assert_equal(ntargets * nchunks, len(evs))
for t in range(ntargets):
assert_equal(len([ev for ev in evs if ev['targets'] == t]),
nchunks)
# now turn `ds` into an eventreleated dataset
erds = eventrelated_dataset(ds, evs)
# the only unprefixed sample attributes are
assert_equal(sorted([a for a in ds.sa if not a.startswith('event')]),
['chunks', 'targets'])
# samples as expected?
assert_array_equal(erds.samples[0],
np.repeat(np.arange(blocklength), nfeatures))
# that should also be the temporal feature offset
assert_array_equal(erds.samples[0], erds.fa.event_offsetidx)
assert_array_equal(erds.sa.event_onsetidx, np.arange(0,71,5))
# finally we should see two mappers
assert_equal(len(erds.a.mapper), 2)
assert_true(isinstance(erds.a.mapper[0], BoxcarMapper))
assert_true(isinstance(erds.a.mapper[1], FlattenMapper))
# check alternative event mapper
# this one does temporal compression by averaging
erds_compress = eventrelated_dataset(
ds, evs, event_mapper=FxMapper('features', np.mean))
assert_equal(len(erds), len(erds_compress))
assert_array_equal(erds_compress.samples[:,0], np.arange(2,73,5))
#
# now check the same dataset with event descretization
tr = 2.5
ds.sa['time'] = np.arange(nchunks * ntargets * blocklength) * tr
evs = [{'onset': 4.9, 'duration': 6.2}]
# doesn't work without conversion
assert_raises(ValueError, eventrelated_dataset, ds, evs)
erds = eventrelated_dataset(ds, evs, time_attr='time')
assert_equal(len(erds), 1)
assert_array_equal(erds.samples[0], np.repeat(np.arange(1,5), nfeatures))
assert_array_equal(erds.sa.orig_onset, [evs[0]['onset']])
assert_array_equal(erds.sa.orig_duration, [evs[0]['duration']])
assert_array_almost_equal(erds.sa.orig_offset, [2.4])
assert_array_equal(erds.sa.time, [np.arange(2.5, 11, 2.5)])
# now with closest match
erds = eventrelated_dataset(ds, evs, time_attr='time', match='closest')
expected_nsamples = 3
assert_equal(len(erds), 1)
assert_array_equal(erds.samples[0],
np.repeat(np.arange(2,2+expected_nsamples),
nfeatures))
assert_array_equal(erds.sa.orig_onset, [evs[0]['onset']])
assert_array_equal(erds.sa.orig_duration, [evs[0]['duration']])
assert_array_almost_equal(erds.sa.orig_offset, [-0.1])
assert_array_equal(erds.sa.time, [np.arange(5.0, 11, 2.5)])
# now test the way back
results = np.arange(erds.nfeatures)
assert_array_equal(erds.a.mapper.reverse1(results),
results.reshape(expected_nsamples, nfeatures))
# what about multiple results?
nresults = 5
results = dataset_wizard([results] * nresults)
# and let's have an attribute to make it more difficult
results.sa['myattr'] = np.arange(5)
rds = erds.a.mapper.reverse(results)
assert_array_equal(rds,
results.samples.reshape(nresults * expected_nsamples,
nfeatures))
assert_array_equal(rds.sa.myattr, np.repeat(results.sa.myattr,
expected_nsamples))
def normalize_dataset(ds, **kwargs):
import collections
import fractions
mean = False
normalization = 'feature'
chunk_number = None
for arg in kwargs:
if (arg == 'mean_samples'):
mean = kwargs[arg]
if (arg == 'img_dim'):
img_dim = int(kwargs[arg])
if (arg == 'normalization'):
normalization = str(kwargs[arg])
if (arg == 'chunk_number'):
chunk_number = kwargs[arg]
n_targets = np.array(
[value for value in collections.Counter(ds.targets).values()]).min()
if chunk_number == 'adaptive':
n_chunks = np.max(
[fractions.gcd(n_targets, i) for i in np.arange(2, 10)])
if n_chunks == 1:
n_chunks = 4
elif isinstance(chunk_number, int):
n_chunks = int(chunk_number)
if chunk_number != None:
argsort = np.argsort(ds.targets)
chunks = []
for _ in ds.uniquetargets:
chunk = np.linspace(0,
n_chunks,
n_targets,
endpoint=False,
dtype=np.int)
chunks.append(chunk)
ds.chunks[argsort] = np.hstack(chunks)
if str(mean) == 'True':
logger.info('Dataset preprocessing: Averaging samples...')
avg_mapper = mean_group_sample(['event_num'])
ds = ds.get_mapped(avg_mapper)
if normalization == 'feature' or normalization == 'both':
logger.info('Dataset preprocessing: Normalization feature-wise...')
if img_dim == 4:
zscore(ds, chunks_attr='file')
zscore(ds) #, param_est=('targets', ['fixation']))
if normalization == 'sample' or normalization == 'both':
# Normalizing image-wise
logger.info('Dataset preprocessing: Normalization sample-wise...')
ds.samples -= np.mean(ds, axis=1)[:, None]
ds.samples /= np.std(ds, axis=1)[:, None]
ds.samples[np.isnan(ds.samples)] = 0
# Find event related stuff
ds.a.events = find_events( #event= ds.sa.event_num,
chunks=ds.sa.chunks, targets=ds.sa.targets)
return ds
def test_erdataset():
# 3 chunks, 5 targets, blocks of 5 samples each
nchunks = 3
ntargets = 5
blocklength = 5
nfeatures = 10
targets = np.tile(np.repeat(range(ntargets), blocklength), nchunks)
chunks = np.repeat(np.arange(nchunks), ntargets * blocklength)
samples = np.repeat(np.arange(nchunks * ntargets * blocklength),
nfeatures).reshape(-1, nfeatures)
ds = dataset_wizard(samples, targets=targets, chunks=chunks)
# check if events are determined properly
evs = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
for ev in evs:
assert_equal(ev['duration'], blocklength)
assert_equal(ntargets * nchunks, len(evs))
for t in range(ntargets):
assert_equal(len([ev for ev in evs if ev['targets'] == t]), nchunks)
# now turn `ds` into an eventreleated dataset
erds = eventrelated_dataset(ds, evs)
# the only unprefixed sample attributes are
assert_equal(sorted([a for a in ds.sa if not a.startswith('event')]),
['chunks', 'targets'])
# samples as expected?
assert_array_equal(erds.samples[0],
np.repeat(np.arange(blocklength), nfeatures))
# that should also be the temporal feature offset
assert_array_equal(erds.samples[0], erds.fa.event_offsetidx)
assert_array_equal(erds.sa.event_onsetidx, np.arange(0, 71, 5))
# finally we should see two mappers
assert_equal(len(erds.a.mapper), 2)
assert_true(isinstance(erds.a.mapper[0], BoxcarMapper))
assert_true(isinstance(erds.a.mapper[1], FlattenMapper))
# check alternative event mapper
# this one does temporal compression by averaging
erds_compress = eventrelated_dataset(ds,
evs,
event_mapper=FxMapper(
'features', np.mean))
assert_equal(len(erds), len(erds_compress))
assert_array_equal(erds_compress.samples[:, 0], np.arange(2, 73, 5))
#
# now check the same dataset with event descretization
tr = 2.5
ds.sa['time'] = np.arange(nchunks * ntargets * blocklength) * tr
evs = [{'onset': 4.9, 'duration': 6.2}]
# doesn't work without conversion
assert_raises(ValueError, eventrelated_dataset, ds, evs)
erds = eventrelated_dataset(ds, evs, time_attr='time')
assert_equal(len(erds), 1)
assert_array_equal(erds.samples[0], np.repeat(np.arange(1, 5), nfeatures))
assert_array_equal(erds.sa.orig_onset, [evs[0]['onset']])
assert_array_equal(erds.sa.orig_duration, [evs[0]['duration']])
assert_array_almost_equal(erds.sa.orig_offset, [2.4])
assert_array_equal(erds.sa.time, [np.arange(2.5, 11, 2.5)])
# now with closest match
erds = eventrelated_dataset(ds, evs, time_attr='time', match='closest')
expected_nsamples = 3
assert_equal(len(erds), 1)
assert_array_equal(
erds.samples[0],
np.repeat(np.arange(2, 2 + expected_nsamples), nfeatures))
assert_array_equal(erds.sa.orig_onset, [evs[0]['onset']])
assert_array_equal(erds.sa.orig_duration, [evs[0]['duration']])
assert_array_almost_equal(erds.sa.orig_offset, [-0.1])
assert_array_equal(erds.sa.time, [np.arange(5.0, 11, 2.5)])
# now test the way back
results = np.arange(erds.nfeatures)
assert_array_equal(erds.a.mapper.reverse1(results),
results.reshape(expected_nsamples, nfeatures))
# what about multiple results?
nresults = 5
results = dataset_wizard([results] * nresults)
# and let's have an attribute to make it more difficult
results.sa['myattr'] = np.arange(5)
rds = erds.a.mapper.reverse(results)
assert_array_equal(
rds, results.samples.reshape(nresults * expected_nsamples, nfeatures))
assert_array_equal(rds.sa.myattr,
np.repeat(results.sa.myattr, expected_nsamples))
def test_hrf_modeling():
skip_if_no_external('nibabel')
skip_if_no_external('nipy') # ATM relies on NiPy's GLM implementation
ds = load_example_fmri_dataset('25mm') #literal=True)
# TODO: simulate short dataset with known properties and use it
# for testing
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
tr = ds.a.imghdr['pixdim'][4]
for ev in events:
for a in ('onset', 'duration'):
ev[a] = ev[a] * tr
evds = eventrelated_dataset(ds, events, time_attr='time_coords',
condition_attr='targets',
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# same voxels
assert_equal(ds.nfeatures, evds.nfeatures)
assert_array_equal(ds.fa.voxel_indices, evds.fa.voxel_indices)
# one sample for each condition, plus constant
assert_equal(sorted(ds.sa['targets'].unique), sorted(evds.sa.targets))
assert_equal(evds.a.add_regs.sa.regressor_names[0], 'constant')
# with centered data
zscore(ds)
evds_demean = eventrelated_dataset(ds, events, time_attr='time_coords',
condition_attr='targets',
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# after demeaning the constant should consume a lot less
assert(evds.a.add_regs[0].samples.mean()
> evds_demean.a.add_regs[0].samples.mean())
# from eyeballing the sensitivity example -- would be better to test this on
# the tutorial data
assert(evds_demean[evds.sa.targets == 'shoe'].samples.max() \
> evds_demean[evds.sa.targets == 'bottle'].samples.max())
# HRF models
assert('regressors' in evds.sa)
assert('regressors' in evds.a.add_regs.sa)
assert_equal(evds.sa.regressors.shape[1], len(ds))
# custom regressors
evds_regrs = eventrelated_dataset(ds, events, time_attr='time_coords',
condition_attr='targets',
regr_attrs=['time_indices'],
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# verify that nothing screwed up time_coords
assert_equal(ds.sa.time_coords[0], 0)
assert_equal(len(evds_regrs), len(evds))
# one more output sample in .a.add_regs
assert_equal(len(evds_regrs.a.add_regs) - 1, len(evds.a.add_regs))
# comes last before constant
assert_equal('time_indices', evds_regrs.a.add_regs.sa.regressor_names[-2])
# order of main regressors is unchanged
assert_array_equal(evds.sa.targets, evds_regrs.sa.targets)
# custom regressors from external sources
evds_regrs = eventrelated_dataset(ds, events, time_attr='time_coords',
condition_attr='targets',
regr_attrs=['time_coords'],
design_kwargs=dict(drift_model='blank',
add_regs=np.linspace(1, -1, len(ds))[None].T,
add_reg_names=['negative_trend']),
glmfit_kwargs=dict(model='ols'),
model='hrf')
assert_equal(len(evds_regrs), len(evds))
# But we got one more in additional regressors
assert_equal(len(evds_regrs.a.add_regs) - 2, len(evds.a.add_regs))
# comes last before constant
assert_array_equal(['negative_trend', 'time_coords', 'constant'],
evds_regrs.a.add_regs.sa.regressor_names)
# order is otherwise unchanged
assert_array_equal(evds.sa.targets, evds_regrs.sa.targets)
# HRF models with estimating per each chunk
assert_equal(ds.sa.time_coords[0], 0)
evds_regrs = eventrelated_dataset(ds, events, time_attr='time_coords',
condition_attr=['targets', 'chunks'],
regr_attrs=['time_indices'],
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
assert_true('add_regs' in evds_regrs.a)
assert_true('time_indices' in evds_regrs.a.add_regs.sa.regressor_names)
assert_equal(len(ds.UC) * len(ds.UT), len(evds_regrs))
assert_equal(len(evds_regrs.UC) * len(evds_regrs.UT), len(evds_regrs))
from mvpa2.mappers.fx import mean_group_sample
evds_regrs_meaned = mean_group_sample(['targets'])(evds_regrs)
assert_array_equal(evds_regrs_meaned.T, evds.T) # targets should be the same
def build_events_ds(ds, new_duration, **kwargs):
"""
This function is used to convert a dataset in a event_related dataset. Used for
transfer learning and clustering, thus a classifier has been trained on a
event related dataset and the prediction should be done on the same kind of the
dataset.
Parameters
----------
ds : Dataset
The dataset to be converted
new_duration : integer
Is the duration of the single event, if experiment events are of different
length, it takes the events greater or equal to new_duration.
kwarsg : dict
win_number: is the number of window of one single event to be extracted,
if it is not setted, it assumes the ratio between event duration and new_duration
overlap:
Returns
-------
Dataset:
the event_related dataset
"""
for arg in kwargs:
if arg == 'win_number':
win_number = kwargs[arg]
if arg == 'overlap':
overlap = kwargs[arg]
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
labels = np.unique(ds.targets)
current_duration = dict()
for l in labels:
d = [e['duration'] for e in events if e['targets'] == l]
current_duration[l] = np.unique(d)[0]
def calc_overlap(w, l, n):
return w - np.floor((l - w) / (n - 1))
def calc_win_number(w, l, o):
return (l - w) / (w - o) + 1
if 'overlap' not in locals():
overlap = calc_overlap(new_duration, current_duration[l], win_number)
else:
if overlap >= new_duration:
overlap = new_duration - 1
if 'win_number' not in locals():
#win_number = np.ceil(current_duration[l]/np.float(new_duration))
win_number = calc_win_number(new_duration, current_duration[l],
overlap)
new_event_list = []
for e in events:
onset = e['onset']
chunks = e['chunks']
targets = e['targets']
duration = e['duration']
for i in np.arange(win_number):
new_onset = onset + i * (new_duration - overlap)
new_event = dict()
new_event['onset'] = new_onset
new_event['duration'] = new_duration
new_event['targets'] = targets
new_event['chunks'] = chunks
new_event_list.append(new_event)
logger.info('Building new event related dataset...')
evds = eventrelated_dataset(ds, events=new_event_list)
return evds
def test_hrf_modeling():
skip_if_no_external('nibabel')
skip_if_no_external('nipy') # ATM relies on NiPy's GLM implementation
ds = load_example_fmri_dataset('25mm') #literal=True)
# TODO: simulate short dataset with known properties and use it
# for testing
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
tr = ds.a.imghdr['pixdim'][4]
for ev in events:
for a in ('onset', 'duration'):
ev[a] = ev[a] * tr
evds = eventrelated_dataset(ds,
events,
time_attr='time_coords',
condition_attr='targets',
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# same voxels
assert_equal(ds.nfeatures, evds.nfeatures)
assert_array_equal(ds.fa.voxel_indices, evds.fa.voxel_indices)
# one sample for each condition, plus constant
assert_equal(sorted(ds.sa['targets'].unique), sorted(evds.sa.targets))
assert_equal(evds.a.add_regs.sa.regressor_names[0], 'constant')
# with centered data
zscore(ds)
evds_demean = eventrelated_dataset(ds,
events,
time_attr='time_coords',
condition_attr='targets',
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# after demeaning the constant should consume a lot less
assert (evds.a.add_regs[0].samples.mean() >
evds_demean.a.add_regs[0].samples.mean())
# from eyeballing the sensitivity example -- would be better to test this on
# the tutorial data
assert(evds_demean[evds.sa.targets == 'shoe'].samples.max() \
> evds_demean[evds.sa.targets == 'bottle'].samples.max())
# HRF models
assert ('regressors' in evds.sa)
assert ('regressors' in evds.a.add_regs.sa)
assert_equal(evds.sa.regressors.shape[1], len(ds))
# custom regressors
evds_regrs = eventrelated_dataset(ds,
events,
time_attr='time_coords',
condition_attr='targets',
regr_attrs=['time_indices'],
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
# verify that nothing screwed up time_coords
assert_equal(ds.sa.time_coords[0], 0)
assert_equal(len(evds_regrs), len(evds))
# one more output sample in .a.add_regs
assert_equal(len(evds_regrs.a.add_regs) - 1, len(evds.a.add_regs))
# comes last before constant
assert_equal('time_indices', evds_regrs.a.add_regs.sa.regressor_names[-2])
# order of main regressors is unchanged
assert_array_equal(evds.sa.targets, evds_regrs.sa.targets)
# custom regressors from external sources
evds_regrs = eventrelated_dataset(
ds,
events,
time_attr='time_coords',
condition_attr='targets',
regr_attrs=['time_coords'],
design_kwargs=dict(drift_model='blank',
add_regs=np.linspace(1, -1, len(ds))[None].T,
add_reg_names=['negative_trend']),
glmfit_kwargs=dict(model='ols'),
model='hrf')
assert_equal(len(evds_regrs), len(evds))
# But we got one more in additional regressors
assert_equal(len(evds_regrs.a.add_regs) - 2, len(evds.a.add_regs))
# comes last before constant
assert_array_equal(['negative_trend', 'time_coords', 'constant'],
evds_regrs.a.add_regs.sa.regressor_names)
# order is otherwise unchanged
assert_array_equal(evds.sa.targets, evds_regrs.sa.targets)
# HRF models with estimating per each chunk
assert_equal(ds.sa.time_coords[0], 0)
evds_regrs = eventrelated_dataset(ds,
events,
time_attr='time_coords',
condition_attr=['targets', 'chunks'],
regr_attrs=['time_indices'],
design_kwargs=dict(drift_model='blank'),
glmfit_kwargs=dict(model='ols'),
model='hrf')
assert_true('add_regs' in evds_regrs.a)
assert_true('time_indices' in evds_regrs.a.add_regs.sa.regressor_names)
assert_equal(len(ds.UC) * len(ds.UT), len(evds_regrs))
assert_equal(len(evds_regrs.UC) * len(evds_regrs.UT), len(evds_regrs))
from mvpa2.mappers.fx import mean_group_sample
evds_regrs_meaned = mean_group_sample(['targets'])(evds_regrs)
assert_array_equal(evds_regrs_meaned.T,
evds.T) # targets should be the same
def spatiotemporal(ds, **kwargs):
onset = 0
for arg in kwargs:
if (arg == 'onset'):
onset = kwargs[arg]
if (arg == 'duration'):
duration = kwargs[arg]
if (arg == 'enable_results'):
enable_results = kwargs[arg]
if (arg == 'permutations'):
permutations = int(kwargs[arg])
events = find_events(targets=ds.sa.targets, chunks=ds.sa.chunks)
if 'duration' in locals():
events = [e for e in events if e['duration'] >= duration]
else:
duration = np.min([ev['duration'] for ev in events])
for e in events:
e['onset'] += onset
e['duration'] = duration
evds = eventrelated_dataset(ds, events=events)
[fclf, cvte] = setup_classifier(**kwargs)
logger.info('Cross validation is performing ...')
res = cvte(evds)
print(cvte.ca.stats)
if permutations != 0:
print(cvte.ca.null_prob.samples)
dist_len = len(cvte.null_dist.dists())
err_arr = np.zeros(dist_len)
for i in range(dist_len):
err_arr[i] = 1 - cvte.ca.stats.stats['ACC']
total_p_value = np.mean(cvte.null_dist.p(err_arr))
p_value = cvte.ca.null_prob.samples
else:
total_p_value = 0.
p_value = np.array([0, 0])
try:
sensana = fclf.get_sensitivity_analyzer()
res_sens = sensana(evds)
except Exception as err:
allowed_keys = [
'map', 'sensitivities', 'stats', 'mapper', 'classifier', 'ds',
'perm_pvalue', 'p'
]
allowed_results = [
None, None, cvte.ca.stats, evds.a.mapper, fclf, evds, p_value,
total_p_value
]
results_dict = dict(zip(allowed_keys, allowed_results))
results = dict()
if not 'enable_results' in locals():
enable_results = allowed_keys[:]
for elem in enable_results:
if elem in allowed_keys:
results[elem] = results_dict[elem]
return results
sens_comb = res_sens.get_mapped(mean_sample())
mean_map = map2nifti(evds, evds.a.mapper.reverse1(sens_comb))
l_maps = []
for m in res_sens:
maps = ds.a.mapper.reverse1(m)
nifti = map2nifti(evds, maps)
l_maps.append(nifti)
l_maps.append(mean_map)
# Packing results (to be sobstitute with a function)
results = dict()
if not 'enable_results' in locals():
enable_results = [
'map', 'sensitivities', 'stats', 'mapper', 'classifier', 'ds',
'pvalue', 'p'
]
allowed_keys = [
'map', 'sensitivities', 'stats', 'mapper', 'classifier', 'ds',
'pvalue', 'p'
]
allowed_results = [
l_maps, res_sens, cvte.ca.stats, evds.a.mapper, fclf, evds, p_value,
total_p_value
]
results_dict = dict(zip(allowed_keys, allowed_results))
for elem in enable_results:
if elem in allowed_keys:
results[elem] = results_dict[elem]
else:
print('******** ' + elem + ' result is not allowed! *********')
return results
def normalize_dataset(ds, **kwargs):
import collections
import fractions
mean = False
normalization = 'feature'
chunk_number = None
for arg in kwargs:
if (arg == 'mean_samples'):
mean = kwargs[arg]
if (arg == 'img_dim'):
img_dim = int(kwargs[arg])
if (arg == 'normalization'):
normalization = str(kwargs[arg])
if (arg == 'chunk_number'):
chunk_number = kwargs[arg]
n_targets = np.array([value for value in collections.Counter(ds.targets).values()]).min()
if chunk_number == 'adaptive':
n_chunks = np.max([fractions.gcd(n_targets, i) for i in np.arange(2, 10)])
if n_chunks == 1:
n_chunks = 4
elif isinstance(chunk_number, int):
n_chunks = int(chunk_number)
if chunk_number != None:
argsort = np.argsort(ds.targets)
chunks = []
for _ in ds.uniquetargets:
chunk = np.linspace(0, n_chunks, n_targets, endpoint=False, dtype=np.int)
chunks.append(chunk)
ds.chunks[argsort] = np.hstack(chunks)
if str(mean) == 'True':
logger.info('Dataset preprocessing: Averaging samples...')
avg_mapper = mean_group_sample(['event_num'])
ds = ds.get_mapped(avg_mapper)
if normalization == 'feature' or normalization == 'both':
logger.info('Dataset preprocessing: Normalization feature-wise...')
if img_dim == 4:
zscore(ds, chunks_attr='file')
zscore(ds)#, param_est=('targets', ['fixation']))
if normalization == 'sample' or normalization == 'both':
# Normalizing image-wise
logger.info('Dataset preprocessing: Normalization sample-wise...')
ds.samples -= np.mean(ds, axis=1)[:, None]
ds.samples /= np.std(ds, axis=1)[:, None]
ds.samples[np.isnan(ds.samples)] = 0
# Find event related stuff
ds.a.events = find_events(#event= ds.sa.event_num,
chunks = ds.sa.chunks,
targets = ds.sa.targets)
return ds
def spatiotemporal(ds, **kwargs):
onset = 0
for arg in kwargs:
if (arg == 'onset'):
onset = kwargs[arg]
if (arg == 'duration'):
duration = kwargs[arg]
if (arg == 'enable_results'):
enable_results = kwargs[arg]
if (arg == 'permutations'):
permutations = int(kwargs[arg])
events = find_events(targets = ds.sa.targets, chunks = ds.sa.chunks)
if 'duration' in locals():
events = [e for e in events if e['duration'] >= duration]
else:
duration = np.min([ev['duration'] for ev in events])
for e in events:
e['onset'] += onset
e['duration'] = duration
evds = eventrelated_dataset(ds, events = events)
[fclf, cvte] = setup_classifier(**kwargs)
logger.info('Cross validation is performing ...')
res = cvte(evds)
print cvte.ca.stats
if permutations != 0:
print cvte.ca.null_prob.samples
dist_len = len(cvte.null_dist.dists())
err_arr = np.zeros(dist_len)
for i in range(dist_len):
err_arr[i] = 1 - cvte.ca.stats.stats['ACC']
total_p_value = np.mean(cvte.null_dist.p(err_arr))
p_value = cvte.ca.null_prob.samples
else:
total_p_value = 0.
p_value = np.array([0,0])
try:
sensana = fclf.get_sensitivity_analyzer()
res_sens = sensana(evds)
except Exception, err:
allowed_keys = ['map', 'sensitivities', 'stats',
'mapper', 'classifier', 'ds',
'perm_pvalue', 'p']
allowed_results = [None, None, cvte.ca.stats,
evds.a.mapper, fclf, evds,
p_value, total_p_value]
results_dict = dict(zip(allowed_keys, allowed_results))
results = dict()
if not 'enable_results' in locals():
enable_results = allowed_keys[:]
for elem in enable_results:
if elem in allowed_keys:
results[elem] = results_dict[elem]
return results
def run(args):
ds = arg2ds(args.data)
verbose(3, 'Concatenation yielded %i samples with %i features' % ds.shape)
# build list of events
events = []
timebased_events = False
if args.event_attrs is not None:
def_attrs = dict([(k, ds.sa[k].value) for k in args.event_attrs])
events = find_events(**def_attrs)
elif args.csv_events is not None:
if args.csv_events == '-':
csv = sys.stdin.read()
import cStringIO
csv = cStringIO.StringIO(csv)
else:
csv = open(args.csv_events, 'rU')
csvt = _load_csv_table(csv)
if not len(csvt):
raise ValueError("no CSV columns found")
if args.onset_column:
csvt['onset'] = csvt[args.onset_column]
nevents = len(csvt[csvt.keys()[0]])
events = []
for ev in xrange(nevents):
events.append(dict([(k, v[ev]) for k, v in csvt.iteritems()]))
elif args.onsets is not None:
if not len(args.onsets):
args.onsets = [i for i in sys.stdin]
# time or sample-based?
if args.time_attr is None:
oconv = int
else:
oconv = float
events = [{'onset': oconv(o)} for o in args.onsets]
elif args.fsl_ev3 is not None:
timebased_events = True
from mvpa2.misc.fsl import FslEV3
events = []
for evsrc in args.fsl_ev3:
events.extend(FslEV3(evsrc).to_events())
if not len(events):
raise ValueError("no events defined")
verbose(2, 'Extracting %i events' % len(events))
if args.event_compression is None:
evmap = None
elif args.event_compression == 'mean':
evmap = FxMapper('features', np.mean, attrfx=merge2first)
elif args.event_compression == 'median':
evmap = FxMapper('features', np.median, attrfx=merge2first)
elif args.event_compression == 'min':
evmap = FxMapper('features', np.min, attrfx=merge2first)
elif args.event_compression == 'max':
evmap = FxMapper('features', np.max, attrfx=merge2first)
# convert to event-related ds
evds = eventrelated_dataset(ds, events, time_attr=args.time_attr,
match=args.match_strategy,
event_offset=args.offset,
event_duration=args.duration,
event_mapper=evmap)
# act on all attribute options
evds = process_common_dsattr_opts(evds, args)
# and store
ds2hdf5(evds, args.output, compression=args.hdf5_compression)
return evds
def build_events_ds(ds, new_duration, **kwargs):
"""
This function is used to convert a dataset in a event_related dataset. Used for
transfer learning and clustering, thus a classifier has been trained on a
event related dataset and the prediction should be done on the same kind of the
dataset.
Parameters
----------
ds : Dataset
The dataset to be converted
new_duration : integer
Is the duration of the single event, if experiment events are of different
length, it takes the events greater or equal to new_duration.
kwarsg : dict
win_number: is the number of window of one single event to be extracted,
if it is not setted, it assumes the ratio between event duration and new_duration
overlap:
Returns
-------
Dataset:
the event_related dataset
"""
for arg in kwargs:
if arg == 'win_number':
win_number = kwargs[arg]
if arg == 'overlap':
overlap = kwargs[arg]
events = find_events(targets = ds.sa.targets, chunks = ds.sa.chunks)
labels = np.unique(ds.targets)
current_duration = dict()
for l in labels:
d = [e['duration'] for e in events if e['targets'] == l]
current_duration[l] = np.unique(d)[0]
def calc_overlap(w, l, n):
return w - np.floor((l - w)/(n - 1))
def calc_win_number (w, l, o):
return (l - w)/(w - o) + 1
if 'overlap' not in locals():
overlap = calc_overlap(new_duration, current_duration[l], win_number)
else:
if overlap >= new_duration:
overlap = new_duration - 1
if 'win_number' not in locals():
#win_number = np.ceil(current_duration[l]/np.float(new_duration))
win_number = calc_win_number(new_duration, current_duration[l], overlap)
new_event_list = []
for e in events:
onset = e['onset']
chunks = e['chunks']
targets = e['targets']
duration = e['duration']
for i in np.arange(win_number):
new_onset = onset + i * (new_duration - overlap)
new_event = dict()
new_event['onset'] = new_onset
new_event['duration'] = new_duration
new_event['targets'] = targets
new_event['chunks'] = chunks
new_event_list.append(new_event)
logger.info('Building new event related dataset...')
evds = eventrelated_dataset(ds, events = new_event_list)
return evds
def run(args):
ds = arg2ds(args.data)
verbose(3, 'Concatenation yielded %i samples with %i features' % ds.shape)
# build list of events
events = []
timebased_events = False
if args.event_attrs is not None:
def_attrs = dict([(k, ds.sa[k].value) for k in args.event_attrs])
events = find_events(**def_attrs)
elif args.csv_events is not None:
if args.csv_events == '-':
csv = sys.stdin.read()
import cStringIO
csv = cStringIO.StringIO(csv)
else:
csv = open(args.csv_events, 'rU')
csvt = _load_csv_table(csv)
if not len(csvt):
raise ValueError("no CSV columns found")
if args.onset_column:
csvt['onset'] = csvt[args.onset_column]
nevents = len(csvt[csvt.keys()[0]])
events = []
for ev in xrange(nevents):
events.append(dict([(k, v[ev]) for k, v in csvt.iteritems()]))
elif args.onsets is not None:
if not len(args.onsets):
args.onsets = [i for i in sys.stdin]
# time or sample-based?
if args.time_attr is None:
oconv = int
else:
oconv = float
events = [{'onset': oconv(o)} for o in args.onsets]
elif args.fsl_ev3 is not None:
timebased_events = True
from mvpa2.misc.fsl import FslEV3
events = []
for evsrc in args.fsl_ev3:
events.extend(FslEV3(evsrc).to_events())
if not len(events):
raise ValueError("no events defined")
verbose(2, 'Extracting %i events' % len(events))
if args.event_compression is None:
evmap = None
elif args.event_compression == 'mean':
evmap = FxMapper('features', np.mean, attrfx=merge2first)
elif args.event_compression == 'median':
evmap = FxMapper('features', np.median, attrfx=merge2first)
elif args.event_compression == 'min':
evmap = FxMapper('features', np.min, attrfx=merge2first)
elif args.event_compression == 'max':
evmap = FxMapper('features', np.max, attrfx=merge2first)
# convert to event-related ds
evds = eventrelated_dataset(ds,
events,
time_attr=args.time_attr,
match=args.match_strategy,
event_offset=args.offset,
event_duration=args.duration,
event_mapper=evmap)
# act on all attribute options
evds = process_common_dsattr_opts(evds, args)
# and store
ds2hdf5(evds, args.output, compression=args.hdf5_compression)
return evds
def find_events_dataset(ds, **kwargs):
ds.a.events = find_events( #event= ds.sa.event_num,
chunks=ds.sa.chunks, targets=ds.sa.targets)
return ds
