Exemplo n.º 1
0
def compute(in_file, n_vols, out_file):

    print('reading stimuli')
    st = read_prf_stimuli(n_vols)
    print('making model')
    model, grids, bounds = make_model(st)

    nii = load(in_file)
    data = nii.get_data()

    indices = array(list(ndindex(data.shape[:3])))

    x = data.reshape((-1, data.shape[-1]))

    good_voxels = x.mean(axis=1) > 2500

    x = x[good_voxels, :]
    indices = indices[good_voxels, :]

    bundle = utils.multiprocess_bundle(og.GaussianFit,
                                       model,
                                       x,
                                       grids,
                                       bounds,
                                       indices,
                                       auto_fit=True,
                                       verbose=1,
                                       Ns=3)

    print('starting computation')
    with Pool(40) as pool:
        output = pool.map(utils.parallel_fit, bundle)

    nif = utils.recast_estimation_results(output, nii)
    nif.to_filename(out_file)
Exemplo n.º 2
0
def test_parallel_fit_manual_grids():

    # stimulus features
    viewing_distance = 38
    screen_width = 25
    thetas = np.arange(0, 360, 45)
    num_blank_steps = 0
    num_bar_steps = 30
    ecc = 10
    tr_length = 1.0
    frames_per_tr = 1.0
    scale_factor = 0.10
    pixels_down = 100
    pixels_across = 100
    dtype = ctypes.c_int16
    voxel_index = (1, 2, 3)
    auto_fit = True
    verbose = 1

    # create the sweeping bar stimulus in memory
    bar = simulate_bar_stimulus(pixels_across, pixels_down, viewing_distance,
                                screen_width, thetas, num_bar_steps,
                                num_blank_steps, ecc)

    # create an instance of the Stimulus class
    stimulus = VisualStimulus(bar, viewing_distance, screen_width,
                              scale_factor, tr_length, dtype)

    # initialize the gaussian model
    model = og.GaussianModel(stimulus, utils.double_gamma_hrf)
    model.hrf_delay = 0

    # generate a random pRF estimate
    x = -5.24
    y = 2.58
    sigma = 1.24
    beta = 2.5
    baseline = -0.25

    # create the "data"
    data = model.generate_prediction(x, y, sigma, beta, baseline)

    # set search grid
    x_grid = slice(-5, 4, 5)
    y_grid = slice(-5, 7, 5)
    s_grid = slice(1 / stimulus.ppd, 5.25, 5)
    b_grid = slice(0.1, 4.0, 5)

    # set search bounds
    x_bound = (-12.0, 12.0)
    y_bound = (-12.0, 12.0)
    s_bound = (1 / stimulus.ppd, 12.0)
    b_bound = (1e-8, 1e2)
    m_bound = (None, None)

    # loop over each voxel and set up a GaussianFit object
    grids = (
        x_grid,
        y_grid,
        s_grid,
    )
    bounds = (x_bound, y_bound, s_bound, b_bound, m_bound)

    # make 3 voxels
    all_data = np.array([data, data, data])
    num_voxels = data.shape[0]
    indices = [(1, 2, 3)] * 3

    # bundle the voxels
    bundle = utils.multiprocess_bundle(og.GaussianFit, model, all_data, grids,
                                       bounds, indices)

    # run analysis
    with sharedmem.Pool(np=3) as pool:
        output = pool.map(utils.parallel_fit, bundle)

    # assert equivalence
    for fit in output:
        npt.assert_almost_equal(fit.x, x, 2)
        npt.assert_almost_equal(fit.y, y, 2)
        npt.assert_almost_equal(fit.sigma, sigma, 2)
        npt.assert_almost_equal(fit.beta, beta, 2)
        npt.assert_almost_equal(fit.baseline, baseline, 2)
Exemplo n.º 3
0
def test_recast_estimation_results():

    # stimulus features
    viewing_distance = 38
    screen_width = 25
    thetas = np.arange(0, 360, 45)
    num_blank_steps = 0
    num_bar_steps = 30
    ecc = 10
    tr_length = 1.0
    frames_per_tr = 1.0
    scale_factor = 0.10
    pixels_down = 100
    pixels_across = 100
    dtype = ctypes.c_int16
    voxel_index = (1, 2, 3)
    auto_fit = True
    verbose = 1

    # create the sweeping bar stimulus in memory
    bar = simulate_bar_stimulus(pixels_across, pixels_down, viewing_distance,
                                screen_width, thetas, num_bar_steps,
                                num_blank_steps, ecc)

    # create an instance of the Stimulus class
    stimulus = VisualStimulus(bar, viewing_distance, screen_width,
                              scale_factor, tr_length, dtype)

    # initialize the gaussian model
    model = og.GaussianModel(stimulus, utils.spm_hrf)
    model.hrf_delay = 0

    # generate a random pRF estimate
    x = -5.24
    y = 2.58
    sigma = 1.24
    beta = 2.5
    baseline = -0.25

    # create the "data"
    data = model.generate_prediction(x, y, sigma, beta, baseline)

    # set search grid
    x_grid = utils.grid_slice(-5, 4, 5)
    y_grid = utils.grid_slice(-5, 7, 5)
    s_grid = utils.grid_slice(1 / stimulus.ppd, 5.25, 5)
    b_grid = utils.grid_slice(0.1, 4.0, 5)

    # set search bounds
    x_bound = (-12.0, 12.0)
    y_bound = (-12.0, 12.0)
    s_bound = (1 / stimulus.ppd, 12.0)
    b_bound = (1e-8, 1e2)
    m_bound = (None, None)

    # loop over each voxel and set up a GaussianFit object
    grids = (
        x_grid,
        y_grid,
        s_grid,
    )
    bounds = (x_bound, y_bound, s_bound, b_bound, m_bound)

    # create 3 voxels of data
    all_data = np.array([data, data, data])
    indices = [(0, 0, 0), (0, 0, 1), (0, 0, 2)]

    # bundle the voxels
    bundle = utils.multiprocess_bundle(og.GaussianFit, model, all_data, grids,
                                       bounds, indices)

    # run analysis
    with sharedmem.Pool(np=3) as pool:
        output = pool.map(utils.parallel_fit, bundle)

    # create grid parent
    arr = np.zeros((1, 1, 3))
    grid_parent = nibabel.Nifti1Image(arr, np.eye(4, 4))

    # recast the estimation results
    nif = utils.recast_estimation_results(output, grid_parent)
    dat = nif.get_data()

    # assert equivalence
    npt.assert_almost_equal(np.mean(dat[..., 0]), x)
    npt.assert_almost_equal(np.mean(dat[..., 1]), y)
    npt.assert_almost_equal(np.mean(dat[..., 2]), sigma)
    npt.assert_almost_equal(np.mean(dat[..., 3]), beta)
    npt.assert_almost_equal(np.mean(dat[..., 4]), baseline)

    # recast the estimation results - OVERLOADED
    nif = utils.recast_estimation_results(output, grid_parent, True)
    dat = nif.get_data()

    # assert equivalence
    npt.assert_almost_equal(np.mean(dat[..., 0]), np.arctan2(y, x), 2)
    npt.assert_almost_equal(np.mean(dat[..., 1]), np.sqrt(x**2 + y**2), 2)
    npt.assert_almost_equal(np.mean(dat[..., 2]), sigma)
    npt.assert_almost_equal(np.mean(dat[..., 3]), beta)
    npt.assert_almost_equal(np.mean(dat[..., 4]), baseline)
Exemplo n.º 4
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def test_parallel_fit_manual_grids():

    # stimulus features
    viewing_distance = 38
    screen_width = 25
    thetas = np.arange(0,360,45)
    num_blank_steps = 0
    num_bar_steps = 30
    ecc = 10
    tr_length = 1.0
    frames_per_tr = 1.0
    scale_factor = 0.10
    pixels_down = 100
    pixels_across = 100
    dtype = ctypes.c_int16
    voxel_index = (1,2,3)
    auto_fit = True
    verbose = 1
    
    # create the sweeping bar stimulus in memory
    bar = simulate_bar_stimulus(pixels_across, pixels_down, viewing_distance,
                                screen_width, thetas, num_bar_steps, num_blank_steps, ecc)
                                
    # create an instance of the Stimulus class
    stimulus = VisualStimulus(bar, viewing_distance, screen_width, scale_factor, tr_length, dtype)
    
    # initialize the gaussian model
    model = og.GaussianModel(stimulus, utils.double_gamma_hrf)
    model.hrf_delay = 0
    
    # generate a random pRF estimate
    x = -5.24
    y = 2.58
    sigma = 1.24
    beta = 2.5
    baseline = -0.25
    
    # create the "data"
    data = model.generate_prediction(x, y, sigma, beta, baseline)
    
    # set search grid
    x_grid = slice(-5,4,5)
    y_grid = slice(-5,7,5)
    s_grid = slice(1/stimulus.ppd,5.25,5)
    b_grid = slice(0.1,4.0,5)
    
    # set search bounds
    x_bound = (-12.0,12.0)
    y_bound = (-12.0,12.0)
    s_bound = (1/stimulus.ppd,12.0)
    b_bound = (1e-8,1e2)
    m_bound = (None, None)
    
    # loop over each voxel and set up a GaussianFit object
    grids = (x_grid, y_grid, s_grid,)
    bounds = (x_bound, y_bound, s_bound, b_bound, m_bound)
    
    # make 3 voxels
    all_data = np.array([data,data,data])
    num_voxels = data.shape[0]
    indices = [(1,2,3)]*3
    
    # bundle the voxels
    bundle = utils.multiprocess_bundle(og.GaussianFit, model, all_data, grids, bounds, indices)
    
    # run analysis
    with sharedmem.Pool(np=3) as pool:
        output = pool.map(utils.parallel_fit, bundle)
        
    # assert equivalence
    for fit in output:
        npt.assert_almost_equal(fit.x, x, 2)
        npt.assert_almost_equal(fit.y, y, 2)
        npt.assert_almost_equal(fit.sigma, sigma, 2)
        npt.assert_almost_equal(fit.beta, beta, 2)
        npt.assert_almost_equal(fit.baseline, baseline, 2)
Exemplo n.º 5
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def test_recast_estimation_results():

    # stimulus features
    viewing_distance = 38
    screen_width = 25
    thetas = np.arange(0,360,45)
    num_blank_steps = 0
    num_bar_steps = 30
    ecc = 10
    tr_length = 1.0
    frames_per_tr = 1.0
    scale_factor = 0.10
    pixels_down = 100
    pixels_across = 100
    dtype = ctypes.c_int16
    voxel_index = (1,2,3)
    auto_fit = True
    verbose = 1
    
    # create the sweeping bar stimulus in memory
    bar = simulate_bar_stimulus(pixels_across, pixels_down, viewing_distance,
                                screen_width, thetas, num_bar_steps, num_blank_steps, ecc)
                                
    # create an instance of the Stimulus class
    stimulus = VisualStimulus(bar, viewing_distance, screen_width, scale_factor, tr_length, dtype)
    
    # initialize the gaussian model
    model = og.GaussianModel(stimulus, utils.spm_hrf)
    model.hrf_delay = 0
    
    # generate a random pRF estimate
    x = -5.24
    y = 2.58
    sigma = 1.24
    beta = 2.5
    baseline = -0.25
    
    # create the "data"
    data = model.generate_prediction(x, y, sigma, beta, baseline)
    
    # set search grid
    x_grid = utils.grid_slice(-5,4,5)
    y_grid = utils.grid_slice(-5,7,5)
    s_grid = utils.grid_slice(1/stimulus.ppd,5.25,5)
    b_grid = utils.grid_slice(0.1,4.0,5)
    
    # set search bounds
    x_bound = (-12.0,12.0)
    y_bound = (-12.0,12.0)
    s_bound = (1/stimulus.ppd,12.0)
    b_bound = (1e-8,1e2)
    m_bound = (None,None)
    
    # loop over each voxel and set up a GaussianFit object
    grids = (x_grid, y_grid, s_grid,)
    bounds = (x_bound, y_bound, s_bound, b_bound, m_bound)
    
    # create 3 voxels of data
    all_data = np.array([data,data,data])
    indices = [(0,0,0),(0,0,1),(0,0,2)]
    
    # bundle the voxels
    bundle = utils.multiprocess_bundle(og.GaussianFit, model, all_data, grids, bounds, indices)
    
    # run analysis
    with sharedmem.Pool(np=3) as pool:
        output = pool.map(utils.parallel_fit, bundle)
        
    # create grid parent
    arr = np.zeros((1,1,3))
    grid_parent = nibabel.Nifti1Image(arr,np.eye(4,4))
    
    # recast the estimation results
    nif = utils.recast_estimation_results(output, grid_parent)
    dat = nif.get_data()
    
    # assert equivalence
    npt.assert_almost_equal(np.mean(dat[...,0]), x)
    npt.assert_almost_equal(np.mean(dat[...,1]), y)
    npt.assert_almost_equal(np.mean(dat[...,2]), sigma)
    npt.assert_almost_equal(np.mean(dat[...,3]), beta)
    npt.assert_almost_equal(np.mean(dat[...,4]), baseline)
    
    # recast the estimation results - OVERLOADED
    nif = utils.recast_estimation_results(output, grid_parent, True)
    dat = nif.get_data()
    
    # assert equivalence
    npt.assert_almost_equal(np.mean(dat[...,0]), np.arctan2(y,x),2)
    npt.assert_almost_equal(np.mean(dat[...,1]), np.sqrt(x**2+y**2),2)
    npt.assert_almost_equal(np.mean(dat[...,2]), sigma)
    npt.assert_almost_equal(np.mean(dat[...,3]), beta)
    npt.assert_almost_equal(np.mean(dat[...,4]), baseline)
Exemplo n.º 6
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############################################################################################################################################
#
#   actual fitting
#
############################################################################################################################################

voxel_indices = [(xx, 0, 0) for xx in np.arange(data.shape[1])]

print("starting fitting of {subject}, hemi {hemi}".format(subject=subject,
                                                          hemi=hemi))

bundle = utils.multiprocess_bundle(Fit=css.CompressiveSpatialSummationFit,
                                   model=css_model,
                                   data=data.T,
                                   grids=css_grids,
                                   bounds=css_bounds,
                                   indices=voxel_indices,
                                   auto_fit=True,
                                   verbose=1,
                                   Ns=12)

# run analysis
pool = multiprocessing.Pool(N_PROCS)
output = pool.map(utils.parallel_fit, bundle)

for fit in output:
    estimates[:6, fit.voxel_index[0]] = fit.estimate
    estimates[6, fit.voxel_index[0]] = fit.rsquared

# try to free up memory by closing the pool and joining them with the main thread
pool.close()
Exemplo n.º 7
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            zorder=2)
plt.xticks(fontsize=16)
plt.yticks(fontsize=16)
plt.xlabel('Time', fontsize=18)
plt.ylabel('Amplitude', fontsize=18)
plt.xlim(0, len(fit.data))
plt.legend(loc=0)

## multiprocess 3 voxels
data = [data, data, data]
indices = ([1, 2, 3], [4, 6, 5], [7, 8, 9])
bundle = utils.multiprocess_bundle(og.GaussianFit,
                                   model,
                                   data,
                                   grids,
                                   bounds,
                                   indices,
                                   auto_fit=True,
                                   verbose=1,
                                   Ns=3)

## run
print("popeye will analyze %d voxels across %d cores" % (len(bundle), 3))
with sharedmem.Pool(np=3) as pool:
    t1 = datetime.datetime.now()
    output = pool.map(utils.parallel_fit, bundle)
    t2 = datetime.datetime.now()
    delta = t2 - t1
    print("popeye multiprocessing finished in %s.%s seconds" %
          (delta.seconds, delta.microseconds))