def test_ascm_accuracy():
test_ascm_data_ref = nib.load(dpd.get_data("ascm_test")).get_data()
test_data = nib.load(dpd.get_data("aniso_vox")).get_data()
# the test data was constructed in this manner
mask = test_data > 50
sigma = estimate_sigma(test_data, N=4)
den_small = non_local_means(
test_data,
sigma=sigma,
mask=mask,
patch_radius=1,
block_radius=1,
rician=True)
den_large = non_local_means(
test_data,
sigma=sigma,
mask=mask,
patch_radius=2,
block_radius=1,
rician=True)
S0n = np.array(adaptive_soft_matching(test_data,
den_small, den_large, sigma[0]))
assert_array_almost_equal(S0n, test_ascm_data_ref)
def test_dipy_fit_tensor():
with InTemporaryDirectory() as tmp:
dwi, bval, bvec = get_data("small_25")
# Copy data to tmp directory
shutil.copyfile(dwi, "small_25.nii.gz")
shutil.copyfile(bval, "small_25.bval")
shutil.copyfile(bvec, "small_25.bvec")
# Call script
cmd = ["dipy_fit_tensor", "--mask=none", "small_25.nii.gz"]
out = run_command(" ".join(cmd))
assert_equal(out[0], 0)
# Get expected values
img = nib.load("small_25.nii.gz")
affine = img.get_affine()
shape = img.shape[:-1]
# Check expected outputs
assert_image_shape_affine("small_25_fa.nii.gz", shape, affine)
assert_image_shape_affine("small_25_t2di.nii.gz", shape, affine)
assert_image_shape_affine("small_25_dirFA.nii.gz", shape, affine)
assert_image_shape_affine("small_25_ad.nii.gz", shape, affine)
assert_image_shape_affine("small_25_md.nii.gz", shape, affine)
assert_image_shape_affine("small_25_rd.nii.gz", shape, affine)
with InTemporaryDirectory() as tmp:
dwi, bval, bvec = get_data("small_25")
# Copy data to tmp directory
shutil.copyfile(dwi, "small_25.nii.gz")
shutil.copyfile(bval, "small_25.bval")
shutil.copyfile(bvec, "small_25.bvec")
# Call script
cmd = ["dipy_fit_tensor", "--save-tensor", "--mask=none", "small_25.nii.gz"]
out = run_command(" ".join(cmd))
assert_equal(out[0], 0)
# Get expected values
img = nib.load("small_25.nii.gz")
affine = img.get_affine()
shape = img.shape[:-1]
# Check expected outputs
assert_image_shape_affine("small_25_fa.nii.gz", shape, affine)
assert_image_shape_affine("small_25_t2di.nii.gz", shape, affine)
assert_image_shape_affine("small_25_dirFA.nii.gz", shape, affine)
assert_image_shape_affine("small_25_ad.nii.gz", shape, affine)
assert_image_shape_affine("small_25_md.nii.gz", shape, affine)
assert_image_shape_affine("small_25_rd.nii.gz", shape, affine)
# small_25_tensor saves the tensor as a symmetric matrix following
# the nifti standard.
ten_shape = shape + (1, 6)
assert_image_shape_affine("small_25_tensor.nii.gz", ten_shape,
affine)
def test_fit_dti():
# Let's see whether we can pass a list of files for each one:
fdata1, fbval1, fbvec1 = dpd.get_data('small_101D')
fdata2, fbval2, fbvec2 = dpd.get_data('small_101D')
with nbtmp.InTemporaryDirectory() as tmpdir:
file_dict = dti.fit_dti([fdata1, fdata2],
[fbval1, fbval2],
[fbvec1, fbvec2],
out_dir=tmpdir)
for f in file_dict.values():
npt.assert_(op.exists(f))
def test_nlls_fit_tensor():
"""
Test the implementation of NLLS and RESTORE
"""
b0 = 1000.
bvecs, bval = read_bvec_file(get_data('55dir_grad.bvec'))
gtab = grad.gradient_table(bval, bvecs)
B = bval[1]
#Scale the eigenvalues and tensor by the B value so the units match
D = np.array([1., 1., 1., 0., 0., 1., -np.log(b0) * B]) / B
evals = np.array([2., 1., 0.]) / B
md = evals.mean()
tensor = from_lower_triangular(D)
#Design Matrix
X = dti.design_matrix(bvecs, bval)
#Signals
Y = np.exp(np.dot(X,D))
Y.shape = (-1,) + Y.shape
#Estimate tensor from test signals and compare against expected result
#using non-linear least squares:
tensor_model = dti.TensorModel(gtab, fit_method='NLLS')
tensor_est = tensor_model.fit(Y)
assert_equal(tensor_est.shape, Y.shape[:-1])
assert_array_almost_equal(tensor_est.evals[0], evals)
assert_array_almost_equal(tensor_est.quadratic_form[0], tensor)
assert_almost_equal(tensor_est.md[0], md)
# Using the gmm weighting scheme:
tensor_model = dti.TensorModel(gtab, fit_method='NLLS', weighting='gmm')
assert_equal(tensor_est.shape, Y.shape[:-1])
assert_array_almost_equal(tensor_est.evals[0], evals)
assert_array_almost_equal(tensor_est.quadratic_form[0], tensor)
assert_almost_equal(tensor_est.md[0], md)
# Use NLLS with some actual 4D data:
data, bvals, bvecs = get_data('small_25')
gtab = grad.gradient_table(bvals, bvecs)
tm1 = dti.TensorModel(gtab, fit_method='NLLS')
dd = nib.load(data).get_data()
tf1 = tm1.fit(dd)
tm2 = dti.TensorModel(gtab)
tf2 = tm2.fit(dd)
assert_array_almost_equal(tf1.fa, tf2.fa, decimal=1)
def uniform_seed_grid():
#read bvals,gradients and data
fimg,fbvals, fbvecs = get_data('small_64D')
bvals=np.load(fbvals)
gradients=np.load(fbvecs)
img =ni.load(fimg)
data=img.get_data()
x,y,z,g=data.shape
M=np.mgrid[.5:x-.5:np.complex(0,x),.5:y-.5:np.complex(0,y),.5:z-.5:np.complex(0,z)]
M=M.reshape(3,x*y*z).T
print(M.shape)
print(M.dtype)
for m in M:
print(m)
gqs = GeneralizedQSampling(data,bvals,gradients)
iT=iter(EuDX(gqs.QA,gqs.IN,seeds=M))
T=[]
for t in iT:
T.append(i)
print('lenT',len(T))
assert_equal(len(T), 1221)
def test_eudx_bad_seed():
"""Test passing a bad seed to eudx"""
fimg, fbvals, fbvecs = get_data('small_101D')
img = ni.load(fimg)
affine = img.get_affine()
data = img.get_data()
gtab = gradient_table(fbvals, fbvecs)
tensor_model = TensorModel(gtab)
ten = tensor_model.fit(data)
ind = quantize_evecs(ten.evecs)
seed = [1000000., 1000000., 1000000.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed], a_low=.2)
try:
track = list(eu)
except ValueError as ve:
if ve.args[0] == 'Seed outside boundaries':
print(ve)
print(data.shape)
seed = [1., 5., 8.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed], a_low=.2)
track = list(eu)
seed = [-1., 1000000., 1000000.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed], a_low=.2)
try:
track = list(eu)
except ValueError as ve:
if ve.args[0] == 'Seed outside boundaries':
print(ve)
def test_passing_maskedview():
data = np.ones((2,4,56))
mask = np.array([[True, False, False, True],
[True, False, True, False]])
gtab, bval = read_bvec_file(get_data('55dir_grad.bvec'))
data = data[mask]
mv = MaskedView(mask, data)
tensor = dti.Tensor(mv, bval, gtab.T, min_signal=1e-9)
assert_equal(tensor.shape, (2,4))
assert_equal(tensor.fa().shape, (2,4))
assert_equal(tensor.evals.shape, (2,4,3))
assert_equal(tensor.evecs.shape, (2,4,3,3))
assert_equal(type(tensor.model_params), MaskedView)
assert_array_equal(tensor.mask, mask)
tensor = tensor[0]
assert_equal(tensor.shape, (4,))
assert_equal(tensor.fa().shape, (4,))
assert_equal(tensor.evals.shape, (4,3))
assert_equal(tensor.evecs.shape, (4,3,3))
assert_equal(type(tensor.model_params), MaskedView)
assert_array_equal(tensor.mask, mask[0])
tensor = tensor[0]
assert_equal(tensor.shape, tuple())
assert_equal(tensor.fa().shape, tuple())
assert_equal(tensor.evals.shape, (3,))
assert_equal(tensor.evecs.shape, (3,3))
assert_equal(type(tensor.model_params), np.ndarray)
def test_nnls_jacobian_fucn():
b0 = 1000.
bvecs, bval = read_bvec_file(get_data('55dir_grad.bvec'))
gtab = grad.gradient_table(bval, bvecs)
B = bval[1]
# Scale the eigenvalues and tensor by the B value so the units match
D = np.array([1., 1., 1., 0., 0., 1., -np.log(b0) * B]) / B
# Design Matrix
X = dti.design_matrix(gtab)
# Signals
Y = np.exp(np.dot(X, D))
# Test Jacobian at D
args = [X, Y]
analytical = dti._nlls_jacobian_func(D, *args)
for i in range(len(X)):
args = [X[i], Y[i]]
approx = opt.approx_fprime(D, dti._nlls_err_func, 1e-8, *args)
assert_true(np.allclose(approx, analytical[i]))
# Test Jacobian at zero
D = np.zeros_like(D)
args = [X, Y]
analytical = dti._nlls_jacobian_func(D, *args)
for i in range(len(X)):
args = [X[i], Y[i]]
approx = opt.approx_fprime(D, dti._nlls_err_func, 1e-8, *args)
assert_true(np.allclose(approx, analytical[i]))
def test_masked_array_with_tensor():
data = np.ones((2, 4, 56))
mask = np.array([[True, False, False, True],
[True, False, True, False]])
bvec, bval = read_bvec_file(get_data('55dir_grad.bvec'))
gtab = grad.gradient_table_from_bvals_bvecs(bval, bvec.T)
tensor_model = TensorModel(gtab)
tensor = tensor_model.fit(data, mask=mask)
assert_equal(tensor.shape, (2, 4))
assert_equal(tensor.fa.shape, (2, 4))
assert_equal(tensor.evals.shape, (2, 4, 3))
assert_equal(tensor.evecs.shape, (2, 4, 3, 3))
tensor = tensor[0]
assert_equal(tensor.shape, (4,))
assert_equal(tensor.fa.shape, (4,))
assert_equal(tensor.evals.shape, (4, 3))
assert_equal(tensor.evecs.shape, (4, 3, 3))
tensor = tensor[0]
assert_equal(tensor.shape, tuple())
assert_equal(tensor.fa.shape, tuple())
assert_equal(tensor.evals.shape, (3,))
assert_equal(tensor.evecs.shape, (3, 3))
assert_equal(type(tensor.model_params), np.ndarray)
def test_median_otsu_flow():
with TemporaryDirectory() as out_dir:
data_path, _, _ = get_data('small_25')
volume = nib.load(data_path).get_data()
save_masked = True
median_radius = 3
numpass = 3
autocrop = False
vol_idx = [0]
dilate = 0
mo_flow = MedianOtsuFlow()
mo_flow.run(data_path, out_dir=out_dir, save_masked=save_masked,
median_radius=median_radius, numpass=numpass,
autocrop=autocrop, vol_idx=vol_idx, dilate=dilate)
mask_name = mo_flow.last_generated_outputs['out_mask']
masked_name = mo_flow.last_generated_outputs['out_masked']
masked, mask = median_otsu(volume, median_radius,
numpass, autocrop,
vol_idx, dilate)
result_mask_data = nib.load(join(out_dir, mask_name)).get_data()
npt.assert_array_equal(result_mask_data, mask)
result_masked_data = nib.load(join(out_dir, masked_name)).get_data()
npt.assert_array_equal(result_masked_data, masked)
def get_synthetic_warped_circle(nslices):
#get a subsampled circle
fname_cicle = get_data('reg_o')
circle = np.load(fname_cicle)[::4,::4].astype(floating)
#create a synthetic invertible map and warp the circle
d, dinv = vfu.create_harmonic_fields_2d(64, 64, 0.1, 4)
d = np.asarray(d, dtype=floating)
dinv = np.asarray(dinv, dtype=floating)
mapping = DiffeomorphicMap(2, (64, 64))
mapping.forward, mapping.backward = d, dinv
wcircle = mapping.transform(circle)
if(nslices == 1):
return circle, wcircle
#normalize and form the 3d by piling slices
circle = (circle-circle.min())/(circle.max() - circle.min())
circle_3d = np.ndarray(circle.shape + (nslices,), dtype=floating)
circle_3d[...] = circle[...,None]
circle_3d[...,0] = 0
circle_3d[...,-1] = 0
#do the same with the warped circle
wcircle = (wcircle-wcircle.min())/(wcircle.max() - wcircle.min())
wcircle_3d = np.ndarray(wcircle.shape + (nslices,), dtype=floating)
wcircle_3d[...] = wcircle[...,None]
wcircle_3d[...,0] = 0
wcircle_3d[...,-1] = 0
return circle_3d, wcircle_3d
def test_sphere_scaling_csdmodel():
"""Check that mirroring regularization sphere does not change the result of
the model"""
_, fbvals, fbvecs = get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
gtab = gradient_table(bvals, bvecs)
mevals = np.array(([0.0015, 0.0003, 0.0003],
[0.0015, 0.0003, 0.0003]))
angles = [(0, 0), (60, 0)]
S, sticks = multi_tensor(gtab, mevals, 100., angles=angles,
fractions=[50, 50], snr=None)
hemi = small_sphere
sphere = hemi.mirror()
response = (np.array([0.0015, 0.0003, 0.0003]), 100)
model_full = ConstrainedSphericalDeconvModel(gtab, response,
reg_sphere=sphere)
model_hemi = ConstrainedSphericalDeconvModel(gtab, response,
reg_sphere=hemi)
csd_fit_full = model_full.fit(S)
csd_fit_hemi = model_hemi.fit(S)
assert_array_almost_equal(csd_fit_full.shm_coeff, csd_fit_hemi.shm_coeff)
def test_median_otsu():
fname = get_data('S0_10')
img = nib.load(fname)
data = img.get_data()
data = np.squeeze(data)
dummy_mask = data > data.mean()
data_masked, mask = median_otsu(data, median_radius=3, numpass=2,
autocrop=False, vol_idx=None,
dilate=None)
assert_equal(mask.sum() < dummy_mask.sum(), True)
data2 = np.zeros(data.shape + (2,))
data2[..., 0] = data
data2[..., 1] = data
data2_masked, mask2 = median_otsu(data2, median_radius=3, numpass=2,
autocrop=False, vol_idx=[0, 1],
dilate=None)
assert_equal(mask.sum() == mask2.sum(), True)
_, mask3 = median_otsu(data2, median_radius=3, numpass=2,
autocrop=False, vol_idx=[0, 1],
dilate=1)
assert_equal(mask2.sum() < mask3.sum(), True)
_, mask4 = median_otsu(data2, median_radius=3, numpass=2,
autocrop=False, vol_idx=[0, 1],
dilate=2)
assert_equal(mask3.sum() < mask4.sum(), True)
def test_eudx_further():
""" Cause we love testin.. ;-)
"""
fimg, fbvals, fbvecs = get_data("small_101D")
img = ni.load(fimg)
affine = img.get_affine()
bvals = np.loadtxt(fbvals)
gradients = np.loadtxt(fbvecs).T
data = img.get_data()
ten = Tensor(data, bvals, gradients, thresh=50)
x, y, z = data.shape[:3]
seeds = np.zeros((10 ** 4, 3))
for i in range(10 ** 4):
rx = (x - 1) * np.random.rand()
ry = (y - 1) * np.random.rand()
rz = (z - 1) * np.random.rand()
seeds[i] = np.ascontiguousarray(np.array([rx, ry, rz]), dtype=np.float64)
# print seeds
# """
eu = EuDX(a=ten.fa(), ind=ten.ind(), seeds=seeds, a_low=0.2)
T = [e for e in eu]
# check that there are no negative elements
for t in T:
assert_equal(np.sum(t.ravel() < 0), 0)
"""
def test_eudx():
# read bvals,gradients and data
fimg, fbvals, fbvecs = get_data("small_64D")
bvals = np.load(fbvals)
gradients = np.load(fbvecs)
img = ni.load(fimg)
data = img.get_data()
print(data.shape)
gqs = GeneralizedQSampling(data, bvals, gradients)
ten = Tensor(data, bvals, gradients, thresh=50)
seed_list = np.dot(np.diag(np.arange(10)), np.ones((10, 3)))
iT = iter(EuDX(gqs.qa(), gqs.ind(), seeds=seed_list))
T = []
for t in iT:
T.append(t)
iT2 = iter(EuDX(ten.fa(), ten.ind(), seeds=seed_list))
T2 = []
for t in iT2:
T2.append(t)
print("length T ", sum([length(t) for t in T]))
print("length T2", sum([length(t) for t in T2]))
print(gqs.QA[1, 4, 8, 0])
print(gqs.QA.ravel()[ndarray_offset(np.array([1, 4, 8, 0]), np.array(gqs.QA.strides), 4, 8)])
assert_almost_equal(
gqs.QA[1, 4, 8, 0], gqs.QA.ravel()[ndarray_offset(np.array([1, 4, 8, 0]), np.array(gqs.QA.strides), 4, 8)]
)
assert_almost_equal(sum([length(t) for t in T]), 70.999996185302734, places=3)
assert_almost_equal(sum([length(t) for t in T2]), 56.999997615814209, places=3)
def test_r2_term_odf_sharp():
SNR = None
S0 = 1
angle = 75
_, fbvals, fbvecs = get_data('small_64D') #get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
sphere = get_sphere('symmetric724')
gtab = gradient_table(bvals, bvecs)
mevals = np.array(([0.0015, 0.0003, 0.0003],
[0.0015, 0.0003, 0.0003]))
S, sticks = multi_tensor(gtab, mevals, S0, angles=[(0, 0), (angle, 0)],
fractions=[50, 50], snr=SNR)
mevecs = [all_tensor_evecs(sticks[0]).T,
all_tensor_evecs(sticks[1]).T]
odf_gt = multi_tensor_odf(sphere.vertices, [0.5, 0.5], mevals, mevecs)
odfs_sh = sf_to_sh(odf_gt, sphere, sh_order=8, basis_type=None)
fodf_sh = odf_sh_to_sharp(odfs_sh, sphere, basis=None, ratio=3 / 15.,
sh_order=8, lambda_=1., tau=0.1, r2_term=True)
fodf = sh_to_sf(fodf_sh, sphere, sh_order=8, basis_type=None)
directions_gt, _, _ = peak_directions(odf_gt, sphere)
directions, _, _ = peak_directions(fodf, sphere)
ang_sim = angular_similarity(directions_gt, directions)
assert_equal(ang_sim > 1.9, True)
assert_equal(directions.shape[0], 2)
def test_csd_predict():
"""
"""
SNR = 100
S0 = 1
_, fbvals, fbvecs = get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
gtab = gradient_table(bvals, bvecs)
mevals = np.array(([0.0015, 0.0003, 0.0003],
[0.0015, 0.0003, 0.0003]))
angles = [(0, 0), (60, 0)]
S, sticks = multi_tensor(gtab, mevals, S0, angles=angles,
fractions=[50, 50], snr=SNR)
sphere = get_sphere('symmetric362')
odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])
response = (np.array([0.0015, 0.0003, 0.0003]), S0)
csd = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit = csd.fit(S)
prediction = csd_predict(csd_fit.shm_coeff, gtab, response=response, S0=S0)
npt.assert_equal(prediction.shape[0], S.shape[0])
model_prediction = csd.predict(csd_fit.shm_coeff)
assert_array_almost_equal(prediction, model_prediction)
# Roundtrip tests (quite inaccurate, because of regularization):
assert_array_almost_equal(csd_fit.predict(gtab, S0=S0),S,decimal=1)
assert_array_almost_equal(csd.predict(csd_fit.shm_coeff, S0=S0),S,decimal=1)
def test_exponential_iso():
fdata, fbvals, fbvecs = dpd.get_data()
data_dti = nib.load(fdata).get_data()
gtab_dti = grad.gradient_table(fbvals, fbvecs)
data_multi, gtab_multi = dpd.dsi_deconv_voxels()
for data, gtab in zip([data_dti, data_multi], [gtab_dti, gtab_multi]):
sfmodel = sfm.SparseFascicleModel(
gtab, isotropic=sfm.ExponentialIsotropicModel)
sffit1 = sfmodel.fit(data[0, 0, 0])
sphere = dpd.get_sphere()
odf1 = sffit1.odf(sphere)
pred1 = sffit1.predict(gtab)
SNR = 1000
S0 = 100
mevals = np.array(([0.0015, 0.0005, 0.0005],
[0.0015, 0.0005, 0.0005]))
angles = [(0, 0), (60, 0)]
S, sticks = sims.multi_tensor(gtab, mevals, S0, angles=angles,
fractions=[50, 50], snr=SNR)
sffit = sfmodel.fit(S)
pred = sffit.predict()
npt.assert_(xval.coeff_of_determination(pred, S) > 96)
def test_response_from_mask():
fdata, fbvals, fbvecs = get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
data = nib.load(fdata).get_data()
gtab = gradient_table(bvals, bvecs)
ten = TensorModel(gtab)
tenfit = ten.fit(data)
FA = fractional_anisotropy(tenfit.evals)
FA[np.isnan(FA)] = 0
radius = 3
for fa_thr in np.arange(0, 1, 0.1):
response_auto, ratio_auto, nvoxels = auto_response(gtab,
data,
roi_center=None,
roi_radius=radius,
fa_thr=fa_thr,
return_number_of_voxels=True)
ci, cj, ck = np.array(data.shape[:3]) / 2
mask = np.zeros(data.shape[:3])
mask[ci - radius: ci + radius,
cj - radius: cj + radius,
ck - radius: ck + radius] = 1
mask[FA <= fa_thr] = 0
response_mask, ratio_mask = response_from_mask(gtab, data, mask)
assert_equal(int(np.sum(mask)), nvoxels)
assert_array_almost_equal(response_mask[0], response_auto[0])
assert_almost_equal(response_mask[1], response_auto[1])
assert_almost_equal(ratio_mask, ratio_auto)
def test_eudx_bad_seed():
"""Test passing a bad seed to eudx"""
fimg, fbvals, fbvecs = get_data('small_101D')
img = ni.load(fimg)
affine = img.affine
data = img.get_data()
gtab = gradient_table(fbvals, fbvecs)
tensor_model = TensorModel(gtab)
ten = tensor_model.fit(data)
ind = quantize_evecs(ten.evecs)
sphere = get_sphere('symmetric724')
seed = [1000000., 1000000., 1000000.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed],
odf_vertices=sphere.vertices, a_low=.2)
assert_raises(ValueError, list, eu)
print(data.shape)
seed = [1., 5., 8.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed],
odf_vertices=sphere.vertices, a_low=.2)
track = list(eu)
seed = [-1., 1000000., 1000000.]
eu = EuDX(a=ten.fa, ind=ind, seeds=[seed],
odf_vertices=sphere.vertices, a_low=.2)
assert_raises(ValueError, list, eu)
def test_csd_superres():
""" Check the quality of csdfit with high SH order. """
_, fbvals, fbvecs = get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
gtab = gradient_table(bvals, bvecs)
# img, gtab = read_stanford_hardi()
evals = np.array([[1.5, .3, .3]]) * [[1.], [1.]] / 1000.
S, sticks = multi_tensor(gtab, evals, snr=None, fractions=[55., 45.])
model16 = ConstrainedSphericalDeconvModel(gtab, (evals[0], 3.),
sh_order=16)
fit16 = model16.fit(S)
# print local_maxima(fit16.odf(default_sphere), default_sphere.edges)
d, v, ind = peak_directions(fit16.odf(default_sphere), default_sphere,
relative_peak_threshold=.2,
min_separation_angle=0)
# Check that there are two peaks
assert_equal(len(d), 2)
# Check that peaks line up with sticks
cos_sim = abs((d * sticks).sum(1)) ** .5
assert_(all(cos_sim > .99))
def test_sfm():
fdata, fbvals, fbvecs = dpd.get_data()
data = nib.load(fdata).get_data()
gtab = grad.gradient_table(fbvals, fbvecs)
sfmodel = sfm.SparseFascicleModel(gtab)
sffit1 = sfmodel.fit(data[0, 0, 0])
sphere = dpd.get_sphere("symmetric642")
odf1 = sffit1.odf(sphere)
pred1 = sffit1.predict(gtab)
mask = np.ones(data.shape[:-1])
sffit2 = sfmodel.fit(data, mask)
pred2 = sffit2.predict(gtab)
odf2 = sffit2.odf(sphere)
sffit3 = sfmodel.fit(data)
pred3 = sffit3.predict(gtab)
odf3 = sffit3.odf(sphere)
npt.assert_almost_equal(pred3, pred2, decimal=2)
npt.assert_almost_equal(pred3[0, 0, 0], pred1, decimal=2)
npt.assert_almost_equal(odf3[0, 0, 0], odf1, decimal=2)
npt.assert_almost_equal(odf3[0, 0, 0], odf2[0, 0, 0], decimal=2)
# Fit zeros and you will get back zeros
npt.assert_almost_equal(
sfmodel.fit(np.zeros(data[0, 0, 0].shape)).beta, np.zeros(sfmodel.design_matrix[0].shape[-1])
)
def test_force_overwrite():
with TemporaryDirectory() as out_dir:
data_path, _, _ = get_data('small_25')
mo_flow = MedianOtsuFlow(output_strategy='absolute')
# Generate the first results
mo_flow.run(data_path, out_dir=out_dir)
mask_file = mo_flow.last_generated_outputs['out_mask']
first_time = os.path.getmtime(mask_file)
# re-run with no force overwrite, modified time should not change
mo_flow.run(data_path, out_dir=out_dir)
mask_file = mo_flow.last_generated_outputs['out_mask']
second_time = os.path.getmtime(mask_file)
assert first_time == second_time
# re-run with force overwrite, modified time should change
mo_flow = MedianOtsuFlow(output_strategy='absolute', force=True)
# Make sure that at least one second elapsed, so that time-stamp is
# different (sometimes measured in whole seconds)
time.sleep(1)
mo_flow.run(data_path, out_dir=out_dir)
mask_file = mo_flow.last_generated_outputs['out_mask']
third_time = os.path.getmtime(mask_file)
assert third_time != second_time
def test_restore():
"""
Test the implementation of the RESTORE algorithm
"""
b0 = 1000.
bvecs, bval = read_bvec_file(get_data('55dir_grad.bvec'))
gtab = grad.gradient_table(bval, bvecs)
B = bval[1]
#Scale the eigenvalues and tensor by the B value so the units match
D = np.array([1., 1., 1., 0., 0., 1., -np.log(b0) * B]) / B
evals = np.array([2., 1., 0.]) / B
md = evals.mean()
tensor = from_lower_triangular(D)
#Design Matrix
X = dti.design_matrix(gtab)
#Signals
Y = np.exp(np.dot(X,D))
Y.shape = (-1,) + Y.shape
for drop_this in range(1, Y.shape[-1]):
# RESTORE estimates should be robust to dropping
this_y = Y.copy()
this_y[:, drop_this] = 1.0
tensor_model = dti.TensorModel(gtab, fit_method='restore',
sigma=67.0)
tensor_est = tensor_model.fit(this_y)
assert_array_almost_equal(tensor_est.evals[0], evals, decimal=3)
assert_array_almost_equal(tensor_est.quadratic_form[0], tensor,
decimal=3)
def test_qb_commandline():
with InTemporaryDirectory():
tracks_file = get_data('fornix')
cmd = ["dipy_quickbundles", tracks_file, '--pkl_file', 'mypickle.pkl',
'--out_file', 'tracks300.trk']
out = run_command(cmd)
assert_equal(out[0], 0)
def test_dandelion():
fimg,fbvals,fbvecs=get_data('small_101D')
bvals=np.loadtxt(fbvals)
gradients=np.loadtxt(fbvecs).T
data=nib.load(fimg).get_data()
print(bvals.shape, gradients.shape, data.shape)
sd=SphericalDandelion(data,bvals,gradients)
sdf=sd.spherical_diffusivity(data[5,5,5])
XA=sd.xa()
np.set_printoptions(2)
print XA.min(),XA.max(),XA.mean()
print sdf*10**4
"""
print(sdf.shape)
gq=GeneralizedQSampling(data,bvals,gradients)
sodf=gq.odf(data[5,5,5])
vertices, faces = get_sphere('symmetric362')
print(faces.shape)
peaks,inds=peak_finding(np.squeeze(sdf),faces)
print(peaks, inds)
peaks2,inds2=peak_finding(np.squeeze(sodf),faces)
print(peaks2, inds2)
"""
'''
def test_all_zeros():
bvecs, bvals = read_bvec_file(get_data('55dir_grad.bvec'))
gtab = grad.gradient_table_from_bvals_bvecs(bvals, bvecs.T)
fit_methods = ['LS', 'OLS', 'NNLS', 'RESTORE']
for _ in fit_methods:
dm = dti.TensorModel(gtab)
assert_array_almost_equal(dm.fit(np.zeros(bvals.shape[0])).evals, 0)
def reconst_flow_core(flow, extra_args=[]):
with TemporaryDirectory() as out_dir:
data_path, bval_path, bvec_path = get_data('small_25')
vol_img = nib.load(data_path)
volume = vol_img.get_data()
mask = np.ones_like(volume[:, :, :, 0])
mask_img = nib.Nifti1Image(mask.astype(np.uint8), vol_img.affine)
mask_path = join(out_dir, 'tmp_mask.nii.gz')
nib.save(mask_img, mask_path)
dti_flow = flow()
args = [data_path, bval_path, bvec_path, mask_path]
args.extend(extra_args)
dti_flow.run(*args, out_dir=out_dir)
fa_path = dti_flow.last_generated_outputs['out_fa']
fa_data = nib.load(fa_path).get_data()
assert_equal(fa_data.shape, volume.shape[:-1])
tensor_path = dti_flow.last_generated_outputs['out_tensor']
tensor_data = nib.load(tensor_path)
assert_equal(tensor_data.shape[-1], 6)
assert_equal(tensor_data.shape[:-1], volume.shape[:-1])
ga_path = dti_flow.last_generated_outputs['out_ga']
ga_data = nib.load(ga_path).get_data()
assert_equal(ga_data.shape, volume.shape[:-1])
rgb_path = dti_flow.last_generated_outputs['out_rgb']
rgb_data = nib.load(rgb_path)
assert_equal(rgb_data.shape[-1], 3)
assert_equal(rgb_data.shape[:-1], volume.shape[:-1])
md_path = dti_flow.last_generated_outputs['out_md']
md_data = nib.load(md_path).get_data()
assert_equal(md_data.shape, volume.shape[:-1])
ad_path = dti_flow.last_generated_outputs['out_ad']
ad_data = nib.load(ad_path).get_data()
assert_equal(ad_data.shape, volume.shape[:-1])
rd_path = dti_flow.last_generated_outputs['out_rd']
rd_data = nib.load(rd_path).get_data()
assert_equal(rd_data.shape, volume.shape[:-1])
mode_path = dti_flow.last_generated_outputs['out_mode']
mode_data = nib.load(mode_path).get_data()
assert_equal(mode_data.shape, volume.shape[:-1])
evecs_path = dti_flow.last_generated_outputs['out_evec']
evecs_data = nib.load(evecs_path).get_data()
assert_equal(evecs_data.shape[-2:], tuple((3, 3)))
assert_equal(evecs_data.shape[:-2], volume.shape[:-1])
evals_path = dti_flow.last_generated_outputs['out_eval']
evals_data = nib.load(evals_path).get_data()
assert_equal(evals_data.shape[-1], 3)
assert_equal(evals_data.shape[:-1], volume.shape[:-1])
def test_btable_prepare():
sq2 = np.sqrt(2) / 2.
bvals = 1500 * np.ones(7)
bvals[0] = 0
bvecs = np.array([[0, 0, 0],
[1, 0, 0],
[0, 1, 0],
[0, 0, 1],
[sq2, sq2, 0],
[sq2, 0, sq2],
[0, sq2, sq2]])
bt = gradient_table(bvals, bvecs)
npt.assert_array_equal(bt.bvecs, bvecs)
bt.info
fimg, fbvals, fbvecs = get_data('small_64D')
bvals = np.load(fbvals)
bvecs = np.load(fbvecs)
bvecs = np.where(np.isnan(bvecs), 0, bvecs)
bt = gradient_table(bvals, bvecs)
npt.assert_array_equal(bt.bvecs, bvecs)
bt2 = gradient_table(bvals, bvecs.T)
npt.assert_array_equal(bt2.bvecs, bvecs)
btab = np.concatenate((bvals[:, None], bvecs), axis=1)
bt3 = gradient_table(btab)
npt.assert_array_equal(bt3.bvecs, bvecs)
npt.assert_array_equal(bt3.bvals, bvals)
bt4 = gradient_table(btab.T)
npt.assert_array_equal(bt4.bvecs, bvecs)
npt.assert_array_equal(bt4.bvals, bvals)
# Test for proper inputs (expects either bvals/bvecs or 4 by n):
assert_raises(ValueError, gradient_table, bvecs)
def test_eudx_further():
""" Cause we love testin.. ;-)
"""
fimg,fbvals,fbvecs=get_data('small_101D')
img=ni.load(fimg)
affine=img.get_affine()
data=img.get_data()
gtab = gradient_table(fbvals, fbvecs)
tensor_model = TensorModel(gtab)
ten = tensor_model.fit(data)
x,y,z=data.shape[:3]
seeds=np.zeros((10**4,3))
for i in range(10**4):
rx=(x-1)*np.random.rand()
ry=(y-1)*np.random.rand()
rz=(z-1)*np.random.rand()
seeds[i]=np.ascontiguousarray(np.array([rx,ry,rz]),dtype=np.float64)
ind = quantize_evecs(ten.evecs)
eu=EuDX(a=ten.fa, ind=ind, seeds=seeds, a_low=.2)
T=[e for e in eu]
#check that there are no negative elements
for t in T:
assert_equal(np.sum(t.ravel()<0),0)
