A crystal in the corpus was reported as two because the grid point joining its halves
scored 0.498 - two thousandths under the threshold. That is an artefact of putting a
hard edge through a continuous quantity, not a gap in a crystal.
The patch search is now hysteresis. A patch is labelled at a lower grow threshold
(0.35) and kept only if it holds a cell above the seed threshold (0.50), which is the
same thing as growing out of the seeds in one pass of the labeller rather than two. A
cell between the two levels joins a crystal that already exists but can never start
one, so no lowering of the grow threshold can turn a background into a crystal - and
the negatives are safe by construction, since water peaks at 0.146 and ice at 0.490,
both under the seed level.
Both halves of the small-patch rule read the GROWN patch - the count includes the
cells growth added and the peak is the patch's best cell wherever it lies - which is
stated at the test, because a reader will otherwise wonder whether a grown cell can
rescue a patch no seed would have admitted. It cannot: the patch is discarded before
that test unless it holds a seed.
The reported extents are those of the grown patch, so they reach the 0.35 contour. Over
the corpus that is major_um x1.04 and n_images x1.07 at the median (x1.11 and x1.14 at
the mean, +7% cells overall), and the cells it adds are spread fairly evenly over
0.35-0.50 rather than piled at the bottom - a crystal edge sampled at one grid step, not
bleed into a neighbour that never diffracted. The patch mean falls with them, and can now
sit below the seed threshold; the peak beside it is what the admission was decided on.
RASTER_REPORT_VERSION is 3, because N_CELLS and the extents are a different measurement
under the same names.
The corpus table is unchanged: 17/17 protein, 0/4 water, 0/3 ice, 10/10 heldout. The
split heals into one crystal, and one raster's five patches become three.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EFEJG6WBQv8th4UJFNe53N