Completes c6912e2a0 (whose message was a placeholder). What the two commits do:
- tNCS by half a lattice vector v: copies v apart weaken the reflections with h.v half-integral, and a
placement moved by (v + o)/2 (o an origin shift of the group) fits the strong ones exactly as well.
The candidate the choice falls on is compared with every such move of itself (rigid body refined,
packing) by R over the weakened reflections only; a move better by 0.01 is taken instead, and where
the two best are within 0.01 the merge is UNDECIDED.
- With tNCS, the group the merge was made in, searched to fewer copies than the chosen group, keeps
the merge UNDECIDED (not for its enantiomorph, which the hand check decides): its first copy alone
can sit at half the vector, and no placement of the chosen group, which may sit there itself, rules
it out.
- P1: the first copy sits at the origin, which no function of its position can single out (the
translation function is flat), so one copy stands out where its rotation-function Z reaches 8; the
null then judges it as before.
Checked against the deposited coordinates (placement comparison, symmetry/origin/setting matched):
two half-vector-shifted placements that had been decided (a SPACE_GROUP in the wrong setting, an
AGREES off by a/4) are UNDECIDED; two UNDECIDED tNCS sets are now AGREES with confirmed placements;
the nine confirmed tNCS placements and the ENANTIOMORPH stay; a P1 single copy with a perfect-match
prediction is placed (confirmed), a wrong PAE-domain placement in P1 (RF Z 6.4) is not.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EizBKhTqrAYago9KJG3dA3