CL_dat_scaleConvert

Description

• Converts a date from one time scale to another.

  The available time scales are TREF, TT, TAI, UT1, UTC, TDB and TCB.

  See Dates and time scales for more details.

• Notes:

  - The input and output dates must be of the same type ("cjd").

  - If both ts_in and ts_out are different from UT1 and TREF, the value of ut1_tref has no influence on the results.

  - If both ts_in and ts_out are different from TT and TREF, the value of tt_tref has no influence on the results.

  - TDB is supposed identical to TT.

Parameters

type_in:

(string) Input time scale: "TREF", "TT", "TAI", "UT1", "UTC", "TDB", "TCB" (1x1)

type_out:

(string) Output time scale: "TREF", "TT", "TAI", "UT1", "UTC", "TDB", "TCB" (1x1)

cjd_in:

Input date (modified julian day from 1950.0). (1xN)

ut1_tref:

(optional) UT1-TREF [seconds]. Default is %CL_UT1_TREF (1x1 or 1xN)

tt_tref:

(optional) TT-TREF [seconds]. Default is %CL_TT_TREF (1x1 or 1xN)

cjd_out:

Output date (modified julian day from 1950.0).(1xN)

Authors

• CNES - DCT/SB

Examples

// Example 1: TAI to UTC // Note the "%nan" during the time of the added second (UTC time undefined) dt_sec = -2 : 0.2 : 1.5; cjd_tai = CL_dat_scaleConvert("UTC", "TAI", 21550) + dt_sec / 86400; cjd_utc = CL_dat_scaleConvert("TAI", "UTC", cjd_tai); [dt_sec; (cjd_utc-cjd_tai)*86400]' // Example 2: Offsets between TREF and various time scales (sec) cjd_tref = CL_dat_now() + (-365.25 * 10 : 5 : 0); utc_tref = (CL_dat_scaleConvert("TREF", "UTC", cjd_tref) - cjd_tref) * 86400; tai_tref = (CL_dat_scaleConvert("TREF", "TAI", cjd_tref) - cjd_tref) * 86400; tt_tref = (CL_dat_scaleConvert("TREF", "TT", cjd_tref) - cjd_tref) * 86400; tcb_tref = (CL_dat_scaleConvert("TREF", "TCB", cjd_tref) - cjd_tref) * 86400; scf(); plot(cjd_tref, [utc_tref; tai_tref; tt_tref; tcb_tref], "thickness", 2); CL_g_legend(gca(), ["UTC", "TAI", "TT", "TCB"]); CL_g_stdaxes();