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PTB-MR / mrpro

MR image reconstruction and processing.
https://ptb-mr.github.io/mrpro/
Apache License 2.0
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remove unused radial undersampling parameter from KTrajectorySunflowerGoldenRpe #563

Open fzimmermann89 opened 6 days ago

fzimmermann89 commented 6 days ago

In KTrajectorySunflowerGoldenRpe, you can set an unused undersampling parameter.

I am currently refactoring the acq_info and trajectory calculators. For now, I will only throw an notimplementederror if the undersampling factor is set to anything but 1.0, Later on, this parameter should either be removed or implemented.

https://github.com/PTB-MR/mrpro/blob/82801e6528352e6ef9af6a4db3b04b740e6485da/src/mrpro/data/traj_calculators/KTrajectorySunflowerGoldenRpe.py#L23

fzimmermann89 commented 6 days ago

@ckolbPTB Or am i missing how it is supposed to work?

ckolbPTB commented 5 days ago

Must be left over from something we in the end did not use. Feel free to already remove the parameter during the refactoring.

on a side note: RPE is not a radial trajectory but a Cartesian trajectory

fzimmermann89 commented 5 days ago

No I am confused - maybe I misunderstood RPE.

I always thought RPE is readout lines in kz direction going through points in the kx plane that are arranged in a radial pattern. So you have to do a fft along kz followed by 2d Nufft along kxky

Why is this considered Cartesian?

Are kxky acquired pseudo radial on Cartesian grid points? This would make it a bit difficult to describe the pattern - how do you do the rounding to grid coordinates? There is some ambiguity...