leonarski_fandClaude Opus 5
2c51e00aae
The Bravais class is decided from the UNREFINED FFT candidate against a fixed 3 degree angular tolerance (LatticeSearch). A lattice that is pseudo-symmetric to a few tenths of a degree is therefore promoted a class too far, and the constraint then snaps a real angle to the ideal one - which throws nearly every reflection of every frame out of tolerance. Measured on a monoclinic crystal that is pseudo-C-orthorhombic to 0.42 degrees: the promoted cell indexes 2 of 60 validation frames and the run dies, where its own primitive cell indexes 39. It is the same lattice in a different setting, b_oC = -(a + 2c), volume exactly 2.00x. The perverse part is that BETTER SPOTS MAKE IT WORSE. LatticeSearch applied to the true cell returns the promoted class deterministically; runs that succeed escape only because the raw FFT candidate is inaccurate enough to miss the promotion window. So it is bistable and non-monotone in every knob - 190 spots per image gives 44/60, 195 gives 12/60, 200 gives 2/60 - and it will bite harder as spot finding improves. The indexer already refines a free triclinic cell alongside each constrained candidate, but decides between them on the fraction of the accumulated first-pass cloud that indexes, where the two differ by less than a factor 2 (measured 0.243 vs 0.135, missing both of that guard's bars). The caller has a far sharper statistic: it already counts how many of 60 validation frames a candidate indexes, and there the same pair differs by more than 20x. So keep the triclinic cell instead of dropping it, and let the first pass settle it. The bar is a clear majority, not a margin, and that is the part that took a battery to get right: the unconstrained refinement holds NO cell parameter fixed, so it can only index at least as many frames as the constrained one, and on genuine symmetry it does index a few more. A 10 % margin - the bar a later scheme needs to displace an earlier one - demoted a real I-centred orthorhombic crystal to P1 (47 -> 54 frames) and perturbed an F-cubic one (49 -> 58). Only a constrained cell that fails outright while its unconstrained cell works is evidence of a false promotion, so demand exactly that. It is the same "fails to index half the frames" test the long-axis rescue below already uses. Battery over 37 rotation crystals: 33/37 space groups matching XDS with one hard failure becomes 34/37 with none, and the other 36 crystals are identical in every printed statistic (checked against a repeat run of the previous binary, which itself differs on one crystal by one observation). The extra validation pass runs only where the constrained cell already failed - 71 ms in a 15 s run - and not at all on the 34 crystals whose constrained cell indexes a majority. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Jungfraujoch
Application to receive data from the PSI JUNGFRAU and EIGER detectors.
All documentation is now placed in docs/ subdirectory and for the current version hosted on Jungfraujoch Read The Docs page.