initialize_3D_phyllotaxis_radial#
- mrinufft.trajectories.trajectory3D.initialize_3D_phyllotaxis_radial(Nc, Ns, nb_interleaves=1, in_out=False)[source]#
Initialize 3D radial trajectories with phyllotactic structure.
The radial shots are oriented according to a Fibonacci sphere lattice, supposed to reproduce the phyllotaxis found in nature through flowers, etc. It ensures an almost uniform distribution.
This function reproduces the proposition from [Pic+11], but the name “spiral phyllotaxis” was changed to avoid confusion with actual spirals.
- Parameters:
Nc (int) – Number of shots
Ns (int) – Number of samples per shot
nb_interleaves (int, optional) – Number of implicit interleaves defining the shots order for a more uniform k-space distribution over time. When the number of interleaves belong to the Fibonacci sequence, the shots from one interleave are structured into a continuous spiral over the surface the k-space sphere, by default 1
in_out (bool, optional) – Whether the curves are going in-and-out or start from the center, by default False
- Returns:
3D phyllotaxis radial trajectory
- Return type:
array_like
References
[Pic+11]Piccini, Davide, Arne Littmann, Sonia Nielles‐Vallespin, and Michael O. Zenge. “Spiral phyllotaxis: the natural way to construct a 3D radial trajectory in MRI.” Magnetic resonance in medicine 66, no. 4 (2011): 1049-1056.