Module eop 

Earth orientation tables: load, interpolate, apply UT1 offsets.

EopData is the table. Each EopDataRow is an epoch, an offset in seconds, and optional polar motion. EopData::eop_offset interpolates to an EopOffset. Loaders take an EopFormat and a Separator. There is no Scale::UT1.

Formats

• EopFormat::C04 — IERS C04 / eopc04. UTC MJD, UT1−UTC.
• EopFormat::Finals2000A — USNO finals. UTC MJD, UT1−UTC; Bulletin B when filled, else A.
• EopFormat::JplEop2 — JPL EOP2. TAI MJD; file TAI−UT1 (ms) stored as UT1−TAI (seconds).
• EopFormat::Custom — column indices via CustomEopCols, or build with EopData::from_rows.

IERS loaders set EopData::epoch_scale to UTC and strip ~1 s leap jumps before interpolating. JPL and custom default to TAI and no leap-strip.

Applying an offset

Dt::to_ut1 / Dt::from_ut1 use the table’s epoch scale. Dt::to_eop / Dt::from_eop take an explicit table epoch (custom / other bodies).

Dt::utc_mjd_to_ut1_mjd maps a UTC MJD float to UT1 MJD (IAU/ERFA leap-day length), which is a different input from a Dt.

Out of range, interpolation holds the nearest endpoint. EopData::merge keeps the base table’s leap-strip and epoch-scale; do not merge IERS with JPL.

Structs

CustomEopCols

For use with EopFormat::Custom.

EopData

Sorted orientation-parameter table for a body.

EopDataRow

One sample in an orientation table.

EopOffset

Interpolated orientation parameters at one epoch.

Enums

EopFormat

File layout for the orientation-table parser.

Separator

Delimiter used to split columns in EOP data files.