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pypulseq/pypulseq/utest_pypulseq_sigpy.py
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utest_pypulseq_sigpy.py
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# sms - check MB
# slr - check slice profile
import unittest
import numpy as np
import sigpy.mri.rf as rf
from pypulseq.opts import Opts
import make_sigpy_pulse as sp
from pulse_opts import pulse_opts
class TestSPulseMethods(unittest.TestCase):
def test_slr(self):
print('Testing SLR design')
time_bw_product = 4
slice_thickness = 3e-3 # Slice thickness
flip_angle = np.pi / 2
# Set system limits
system = Opts(max_grad=32, grad_unit='mT/m', max_slew=130, slew_unit='T/m/s', rf_ringdown_time=30e-6,
rf_dead_time=100e-6)
pulse_cfg = pulse_opts(pulse_type='slr', ptype='st', ftype='ls', d1=0.01, d2=0.01, cancel_alpha_phs=False,
n_bands=3, band_sep=20, phs_0_pt='None')
rfp, gz, _, pulse = sp.sigpy_n_seq(flip_angle=flip_angle, system=system, duration=3e-3,
slice_thickness=slice_thickness,
time_bw_product=4, return_gz=True, pulse_cfg=pulse_cfg)
[a, b] = rf.sim.abrm(pulse, np.arange(-20 * time_bw_product, 20 * time_bw_product, 40 * time_bw_product / 2000),
True)
Mxy = 2 * np.multiply(np.conj(a), b)
# pl.LinePlot(Mxy)
# print(np.sum(np.abs(Mxy)))
# peaks, dict = sis.find_peaks(np.abs(Mxy),threshold=0.5, plateau_size=40)
plateau_widths = np.sum(np.abs(Mxy) > 0.8)
self.assertTrue(29,plateau_widths)
def test_sms(self):
print('Testing SMS design')
time_bw_product = 4
slice_thickness = 3e-3 # Slice thickness
flip_angle = np.pi / 2
n_bands = 3
# Set system limits
system = Opts(max_grad=32, grad_unit='mT/m', max_slew=130, slew_unit='T/m/s', rf_ringdown_time=30e-6,
rf_dead_time=100e-6)
pulse_cfg = pulse_opts(pulse_type='sms', ptype='st', ftype='ls', d1=0.01, d2=0.01, cancel_alpha_phs=False,
n_bands=n_bands, band_sep=20, phs_0_pt='None')
rfp, gz, _, pulse = sp.sigpy_n_seq(flip_angle=flip_angle, system=system, duration=3e-3,
slice_thickness=slice_thickness,
time_bw_product=4, return_gz=True, pulse_cfg=pulse_cfg)
[a, b] = rf.sim.abrm(pulse, np.arange(-20 * time_bw_product, 20 * time_bw_product, 40 * time_bw_product / 2000),
True)
Mxy = 2 * np.multiply(np.conj(a), b)
# pl.LinePlot(Mxy)
# print(np.sum(np.abs(Mxy)))
# peaks, dict = sis.find_peaks(np.abs(Mxy),threshold=0.5, plateau_size=40)
plateau_widths = np.sum(np.abs(Mxy) > 0.8)
self.assertEqual(29*n_bands, plateau_widths) #if slr has 29 > 0.8, then sms with MB = n_bands
if __name__ == '__main__':
unittest.main()
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