fse_sim#
- torchsim.fse_sim(flip, ESP, T1, T2, phases=0.0, TR=1000000.0, exc_flip=90.0, exc_phase=90.0, diff=None, slice_prof=1.0, B1=1.0, M0=1.0, nstates=10, chunk_size=None, device=None)[source]#
Fast Spin Echo simulator wrapper.
- Parameters:
flip (float | npt.ArrayLike) – Refocusing flip angle train in degrees.
ESP (float) – Echo spacing in milliseconds.
phases (float | npt.ArrayLike, optional) – Refocusing flip angle phases in degrees. The default is
90.0.TR (float | npt.ArrayLike, optional) – Repetition time in milliseconds. The default is
1e6.exc_flip (float, optional) – Excitation flip angle train in degrees. The default is
90.0.exc_phase (float, optional) – Excitation flip angle phase in degrees. The default is
0.0.T1 (float | npt.ArrayLike) – Longitudinal relaxation time in milliseconds.
T2 (float | npt.ArrayLike) – Transverse relaxation time in milliseconds.
diff (str | tuple[str], optional) – Arguments to get the signal derivative with respect to. The default is
None(no differentation).slice_prof (float | npt.ArrayLike, optional) – Flip angle scaling along slice profile. The default is
1.0.B1 (float | npt.ArrayLike, optional) – Flip angle scaling map, default is
1.0.inv_efficiency (float | npt.ArrayLike, optional) – Inversion efficiency map, default is
1.0.M0 (float or array-like, optional) – Proton density scaling factor, default is
1.0.TI (float | npt.ArrayLike, optional) – Inversion time in milliseconds. The default is
0.0.nstates (int, optional) – Number of EPG states to be retained. The default is
10.chunk_size (int, optional) – Number of atoms to be simulated in parallel. The default is
None.device (str | torch.device, optional) – Computational device for simulation. The default is
None(infer from input).
- Returns:
sig (npt.ArrayLike) – Signal evolution of shape
(..., len(flip)).jac (npt.ArrayLike) – Derivatives of signal wrt
diffparameters, of shape(..., len(diff), len(flip)). Not returned ifdiffisNone.
