initial push of fieldmaps and test for fieldmaps

[alexjaffray]

Here is my initial commit of the fieldmapping code and the test case (very simple for now but is along the right lines).

Open to suggestions and discussion.

[codecov-commenter]

Codecov Report

Base: 63.05% // Head: 63.05% // No change to project coverage :thumbsup:

Coverage data is based on head (798e512) compared to base (9c9d141). Patch has no changes to coverable lines.

Additional details and impacted files

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[tknopp]

@alexjaffray: I am closing this here, since we decided in https://github.com/MagneticResonanceImaging/MRIReco.jl/issues/132 to move it to another Github Repo https://github.com/MagneticResonanceImaging/MRIfieldmaps.jl. Could you reopen in that repository?

[alexjaffray]

Yes, I can do that.

Thanks, Alex

On Tue, 22 Nov 2022 at 13:54, Tobias Knopp @.***> wrote:

@alexjaffray https://github.com/alexjaffray: I am closing this here, since we decided in #132 https://github.com/MagneticResonanceImaging/MRIReco.jl/issues/132 to move it to another Github Repo https://github.com/MagneticResonanceImaging/MRIfieldmaps.jl. Could you reopen in that repository?

— Reply to this email directly, view it on GitHub https://github.com/MagneticResonanceImaging/MRIReco.jl/pull/133#issuecomment-1324227712, or unsubscribe https://github.com/notifications/unsubscribe-auth/AEFRPBNSSGPTEOZAC4JU22DWJUXI7ANCNFSM6AAAAAARZRNKYY . You are receiving this because you were mentioned.Message ID: @.***>

[alexjaffray]

@JeffFessler Do you think it would be useful to move this code into the MRIFieldmaps.jl repo?

[JeffFessler]

Based on Figs. 4, 6, 9, 11 of our 2020 paper, I am fairly confident that the newer algorithms that I reproduced in MRIFieldmaps.jl will be faster than the QM method from our 2008 paper. I didn't code up the 2008 in the new repo for two reasons: expecting it would be slower, and to avoid duplicating the work you did already on it. Of course those 2020 results were in Matlab so it is possible (but unlikely) that the situation would be different in Julia. Have you tried the new repo and does it produce similar fieldmaps for your data? Is it faster? It would be fine with me to have the 2008 method in the other repo even if it is mainly for historical reasons and to facilitate comparisons, so feel free to make a PR there.

[tknopp]

Yes, the fieldmap methods should go into MRIFieldmaps.jl and I would encourage you @alexjaffray to prepare a PR.