Each fix is covered by a regression test that fails on `main` and
passes on this commit.
Round 1 (initial review):
* propagation: thread `latitude` into the conditions map so
`score_season/4` actually picks up regional multipliers
* hrrr_client / fetcher.rs: `nearest_hrrr_hour` rounds DOWN, never at
a future cycle that NOAA hasn't published yet
* radio: spherical-vector great-circle midpoint replaces the
arithmetic mean — anti-meridian paths no longer fold to Greenwich
* weather: `reconcile_weather_statuses` scales the longitude band by
`1 / cos(lat)` so the bbox stays ~150 km wide at every latitude
* radio/maidenhead: clamp 90°/180° below the field-bucket overflow so
`from_latlon` never emits invalid characters like 'S'
* prop_grid_rs/pipeline: merge HRRR + NEXRAD-derived rain rates and
read `best_duct_freq_ghz` into `best_duct_band_ghz` so the Native
Duct Boost actually fires
* propagation/region (Elixir + Rust): inclusive upper bounds so points
exactly at lat_max get the regional multiplier
* weather/sounding_params (Elixir + Rust): drop the 10 m gradient
floor so HRRR's thin near-surface layers stop hiding sharp ducts
* weather/sounding_params: when the profile ends inside a duct,
finalize it with the highest sample as the top instead of throwing
it away (Rust port already correct)
Round 2 (post-fix sweep):
* radio + commercial: single canonical haversine in Radio (atan2
form); Commercial delegates instead of carrying a second copy that
could disagree at threshold distances
* prop_grid_rs/profiles_file: `snap_coords` matches Elixir's
step-aware snap (`round(coord/0.125) * 0.125`, then 3-dp round) so
Rust-keyed and Elixir-keyed profile maps land on the same cell
* weather/grib2/wgrib2: `parse_lon_val_segment` uses `Float.parse`
uniformly — wgrib2 dropping the trailing `.0` from a longitude no
longer crashes the whole chain step
- identify_var: full round-trip across every known (discipline,
category, number) triple, plus a property that any triple outside
the 12-entry lookup falls back to the "cat:num" default.
- identify_level: hybrid-level and entire-atmosphere branches, plus
two properties — pressure levels always render as
`div(value_pa, 100) <> " mb"` and unknown surface types always
render as `unknown:<type>:<value>` (generator samples only from
types outside the 6-entry lookup set).
- sign_magnitude_16: round-trip property over [-32_767, 32_767] (±0
both decode to 0 as intended) and a monotonicity property inside
a single sign band.
Suite: 2,419 tests + 164 properties (was 2,416 + 159); credo strict
clean.
build_messages_per_message/3 was slicing the wgrib2 -lola bin output as
a packed float32 stream, ignoring the 4-byte record-length header + 4-byte
trailer that Fortran unformatted records prepend/append around each
message's data block. First value of message 0 came back as ~2.24e-44
(little-endian float32 of the int-16 record length), and every subsequent
message was shifted by 8 bytes so values spilled into neighbouring cells.
Fix: propagate the correct offset math already used by parse_lola_binary/3
(record_overhead = 8, stride = bytes_per_message + 8, data_offset =
msg_idx * stride + 4).
Flipped the characterization test from metadata-only to per-cell physical
asserts (200 K < TMP, DPT < 340 K; DPT <= TMP) and a 0.01 K cross-check
against extract_grid/3 output on the same fixture + bbox. Latent bug —
no production callers of extract_grid_messages*.
16 characterization tests against real wgrib2 binary + checked-in HRRR
fixtures: extract_grid/3 (bbox + physical sanity on TMP/DPT + longitude
convention), extract_grid_from_file/3, extract_grid_from_file_mapped/4
reducer plumbing, extract_grid_messages/3 metadata, extract_points_from_file/3
nearest-neighbor snap, undefined-value sentinel filtering, empty-match and
error shapes. Tagged @describetag :slow so they run on 'mix test --include
slow' (project default excludes slow, matches existing HRRR/NARR tests).
Surfaces one real bug (not fixed): extract_grid_messages variants don't
account for the 8-byte Fortran record overhead between messages in wgrib2
-lola output, so per-message values after the first are shifted. The
correct offset math exists in parse_lola_binary/3. Tests characterize
current behavior (metadata-only); worth a follow-up fix + value-range
assertions.
Aliases: add module aliases for 9 nested module references
Apply: replace apply/3 with direct module attribute calls
Line length: break 1 long spec line
Refactoring: extract helpers to reduce complexity and nesting
in show.ex, radio.ex, weather workers, terrain, duct detection,
backfill dashboard, contact map, and mix tasks
Add extract_values/3 to SimplePacking and ComplexPacking for batch
index extraction from a single GRIB2 message. Add extract_grid/2 to
Extractor which takes a list of {lat, lon} points and returns all
variable values for each point, skipping points outside the grid.
This enables extracting weather data for many grid points from a
single HRRR download instead of re-parsing per point.
extract_n_values_array used Enum.take(count) on a reversed list
before reversing it, which included padding values from byte
alignment and dropped actual values. When group count * bits
wasn't a multiple of 8, the extra padding bits produced a
phantom value that shifted the entire array by one position.
This caused cascading errors in spatial differencing — values
started correct but diverged exponentially (DPT decoded as
38 billion K instead of 275 K).
Fix: reverse the list first, then take count, so padding values
at the end are discarded instead of actual values at the start.
Instead of returning "malformed section" on trailing bytes or truncated
sections, attempt to return parsed results. This handles older HRRR
files (2019) that have padding bytes after the last section.
Eliminates the external wgrib2 C tool dependency that blocked HRRR
processing. Implements Lambert Conformal projection, simple packing
(Template 5.0), complex packing with spatial differencing (Template 5.3),
and GRIB2 section parsing — enough to extract point values from HRRR
grid data using only Elixir.
