Cosmo vec

Implement cosmological terms in vectorised hydro interactions.

Fixes #406 (closed).

changed the description

I have tested this with make check but are there any other tests for cosmology yet?

I have noticed that you recompute a2_Hubble and fac_mu every call to the interaction function. Can you not compute these terms once in DOPAIR2 and DOSELF2 and pass them to the interaction function? Instead of recomputing them every call to "runner_iact"? Or is that an issue when it comes to the interaction function interface?

It's an interface issue.

Gadget needs these terms. But other schemes might need other terms. The only thing I can guaranty is that any term we will need is always a combination of a and H. Now, in general, I do not think that this is an issue anyway. We are currently bandwidth and register limited, not computing limited. Plus, the fac_mu term is exactly 1 (and implemented as such in the scalar code) for the most common case gamma=5/3.

Ah okay, I wondered if it was SPH scheme dependent.

Yeah, Gizmo will get a different set of factors for instance.

Does that fact change things in your implementation?

Yes, because I would need to change it so that fac_mu and a2_Hubble is computed in the interaction function rather than in DOPAIR2 and DOSELF2. Should I do that?

Yes, please, I think that is best.

added 1 commit

• 0901bce8 - Caclulate cosmological terms inside interaction function.

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Sorted.

Thanks!

I have tested this with make check but are there any other tests for cosmology yet?

I did not respond to this, sorry.

No, no more tests at this stage besides running the EAGLE_xx with cosmology on and checking that you get the same asnswwer as scalar. (Which still does not tell us whether both of them are correct...)

@pdraper for reasons I don't understand, I can't accept this merge request. Has the repository been locked?

No, haven't changed anything.

I briefly see this when clicking the button:

''' merge: failed to rename lockfile to '/var/gitlab/repositories/swift/swiftsim.git/objects/ee/b5eed70c4e0defb416d2f0e8563e2749e47860': Permission denied. Refreshing in 2 seconds to show the updated status...Refresh now'''

Sorry, my fault, when I removed the bad branch I ran "gc" as root, so some files had the wrong owner. Is that working now?

merged

mentioned in commit 11f5d292

Yes, perfect, thanks!