convert_trajectory_to_gradients

convert_trajectory_to_gradients#

mrinufft.trajectories.utils.convert_trajectory_to_gradients(trajectory, norm_factor=0.5, resolution=0.0006, raster_time=0.01, gamma=Gammas.HYDROGEN, get_final_positions=False)[source]#

Derive a normalized trajectory over time to provide gradients.

Parameters:

  • trajectory (np.ndarray) – Normalized trajectory consisting of k-space coordinates in 2D or 3D.

  • norm_factor (float, optional) – Trajectory normalization factor, by default KMAX.

  • resolution (float, np.array, optional) – Resolution of MR image in meters, isotropic as int or anisotropic as np.array. The default is DEFAULT_RESOLUTION.

  • raster_time (float, optional) – Amount of time between the acquisition of two consecutive samples in ms. The default is DEFAULT_RASTER_TIME.

  • gamma (float, optional) – Gyromagnetic ratio of the selected nucleus in kHz/T The default is Gammas.HYDROGEN.

  • get_final_positions (bool, optional) – If True, return the final positions in k-space. The default is False.

Returns:

gradients – Gradients corresponding to trajectory.

Return type:

np.ndarray