object

time_scales_data

Bundled and override data plus constants for UTC/TAI/TT/UT1/TDB/TCG/TCB conversions.

Availability:
logtalk_load(time_scales(loader))
Author: Paulo Moura
Version: 0:2:0
Date: 2026-02-26
Compilation flags:
static, context_switching_calls
Uses:
logtalk
Remarks:
(none)
Inherited public predicates:
(none)

Public predicates

load_leap_seconds_override/1

Loads leap-second override data from a file containing leap(UnixSeconds,OffsetSeconds). terms.

Compilation flags:
static
Template:
load_leap_seconds_override(File)
Mode and number of proofs:
load_leap_seconds_override(+atom) - one
Remarks:

  • Term format: Each term must be of the form leap(UnixSeconds,OffsetSeconds)..

  • Term ordering: Terms must be sorted by increasing UnixSeconds.

  • Value constraints: UnixSeconds must be an integer greater than or equal to 63072000 and OffsetSeconds must be a non-decreasing integer sequence.

clear_leap_seconds_override/0

Clears leap-second override data and reverts to bundled data.

Compilation flags:
static
Mode and number of proofs:
clear_leap_seconds_override - one

leap_seconds_source/1

Returns the active leap-seconds data source as bundled or override.

Compilation flags:
static
Template:
leap_seconds_source(Source)
Mode and number of proofs:
leap_seconds_source(-atom) - one

leap_seconds_entries/1

Returns the active leap-seconds data as an ordered list of leap(UnixSeconds,OffsetSeconds) terms.

Compilation flags:
static
Template:
leap_seconds_entries(Entries)
Mode and number of proofs:
leap_seconds_entries(-list) - one

save_leap_seconds_entries/1

Saves the active leap-seconds data to a file using leap(UnixSeconds,OffsetSeconds). terms.

Compilation flags:
static
Template:
save_leap_seconds_entries(File)
Mode and number of proofs:
save_leap_seconds_entries(+atom) - one

load_dut1_override/1

Loads DUT1 override data from a file containing dut1(UnixSeconds,Numerator,Denominator). terms.

Compilation flags:
static
Template:
load_dut1_override(File)
Mode and number of proofs:
load_dut1_override(+atom) - one
Remarks:

  • Term format: Each term must be of the form dut1(UnixSeconds,Numerator,Denominator)..

  • Term ordering: Terms must be sorted by increasing UnixSeconds.

  • Value constraints: UnixSeconds and Numerator must be integers; Denominator must be a positive integer; UnixSeconds must be greater than or equal to 63072000.

clear_dut1_override/0

Clears DUT1 override data and reverts to bundled data.

Compilation flags:
static
Mode and number of proofs:
clear_dut1_override - one

dut1_source/1

Returns the active DUT1 data source as bundled or override.

Compilation flags:
static
Template:
dut1_source(Source)
Mode and number of proofs:
dut1_source(-atom) - one

dut1_entries/1

Returns the active DUT1 data as an ordered list of dut1(UnixSeconds,Numerator,Denominator) terms.

Compilation flags:
static
Template:
dut1_entries(Entries)
Mode and number of proofs:
dut1_entries(-list) - one

save_dut1_entries/1

Saves the active DUT1 data to a file using dut1(UnixSeconds,Numerator,Denominator). terms.

Compilation flags:
static
Template:
save_dut1_entries(File)
Mode and number of proofs:
save_dut1_entries(+atom) - one

leap_offset_at_utc_unix/2

Returns the TAI-UTC offset in SI seconds for a given UTC Unix epoch second within the supported range.

Compilation flags:
static
Template:
leap_offset_at_utc_unix(UnixSeconds,OffsetSeconds)
Mode and number of proofs:
leap_offset_at_utc_unix(+integer,-integer) - zero_or_one

leap_effective_date/2

Enumerates UTC effective dates for TAI-UTC offset changes and their resulting offset in SI seconds.

Compilation flags:
static
Template:
leap_effective_date(UTCDateTime,OffsetSeconds)
Mode and number of proofs:
leap_effective_date(?compound,?integer) - zero_or_more

tt_minus_tai/2

Returns the constant TT minus TAI offset as a rational value Numerator/Denominator seconds.

Compilation flags:
static
Template:
tt_minus_tai(Numerator,Denominator)
Mode and number of proofs:
tt_minus_tai(-integer,-integer) - one

dut1_offset_at_utc_unix/3

Returns DUT1 (UT1-UTC) at a UTC Unix epoch second as a rational value Numerator/Denominator.

Compilation flags:
static
Template:
dut1_offset_at_utc_unix(UnixSeconds,Numerator,Denominator)
Mode and number of proofs:
dut1_offset_at_utc_unix(+integer,-integer,-integer) - zero_or_one

tdb_minus_tt_approx/3

Returns an approximate TDB-TT offset in seconds for a TT instant represented by integer seconds and normalized fraction.

Compilation flags:
static
Template:
tdb_minus_tt_approx(TTSeconds,Fraction,OffsetSeconds)
Mode and number of proofs:
tdb_minus_tt_approx(+integer,+compound,-float) - one

tcg_minus_tt_approx/3

Returns an approximate TCG-TT offset in seconds for a TT instant represented by integer seconds and normalized fraction.

Compilation flags:
static
Template:
tcg_minus_tt_approx(TTSeconds,Fraction,OffsetSeconds)
Mode and number of proofs:
tcg_minus_tt_approx(+integer,+compound,-float) - one

tcb_minus_tdb_approx/3

Returns an approximate TCB-TDB offset in seconds for a TDB instant represented by integer seconds and normalized fraction.

Compilation flags:
static
Template:
tcb_minus_tdb_approx(TDBSeconds,Fraction,OffsetSeconds)
Mode and number of proofs:
tcb_minus_tdb_approx(+integer,+compound,-float) - one

tai_minus_utc_for_tai_unix/2

Returns the TAI-UTC offset in SI seconds for a given TAI instant represented as Unix-like integer seconds.

Compilation flags:
static
Template:
tai_minus_utc_for_tai_unix(TAISeconds,OffsetSeconds)
Mode and number of proofs:
tai_minus_utc_for_tai_unix(+integer,-integer) - zero_or_one

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)