src/Marando/IAU/iauUt1tt.php
public static function Ut1tt($ut11, $ut12, $dt, &$tt1, &$tt2) {
    $dtd;

    /* Result, safeguarding precision. */
    $dtd = $dt / DAYSEC;
    if ($ut11 > $ut12) {
      $tt1 = $ut11;
      $tt2 = $ut12 + $dtd;
    }
    else {
      $tt1 = $ut11 + $dtd;
      $tt2 = $ut12;
    }

    /* Status (always OK). */
    return 0;
  }
public static function Ut1tt($ut11, $ut12, $dt, &$tt1, &$tt2) {
    $dtd;

    /* Result, safeguarding precision. */
    $dtd = $dt / DAYSEC;
    if ($ut11 > $ut12) {
      $tt1 = $ut11;
      $tt2 = $ut12 + $dtd;
    }
    else {
      $tt1 = $ut11 + $dtd;
      $tt2 = $ut12;
    }

    /* Status (always OK). */
    return 0;
  }
public static function Ut1tt ( $ ut11 , $ ut12 , $ dt , & $ tt1 , & $ tt2 ) { $ dtd ; /* Result, safeguarding precision. */ $ dtd = $ dt / DAYSEC ; if ( $ ut11 > $ ut12 ) { $ tt1 = $ ut11 ; $ tt2 = $ ut12 + $ dtd ; } else { $ tt1 = $ ut11 + $ dtd ; $ tt2 = $ ut12 ; } /* Status (always OK). */ return 0 ; }
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i a u U t 1 t t
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Time scale transformation:  Universal Time, UT1, to Terrestrial
Time, TT.

This function is part of the International Astronomical Union's
SOFA (Standards of Fundamental Astronomy) software collection.

Status:  canonical.

Given:
ut11,ut12  double    UT1 as a 2-part Julian Date
dt         double    TT-UT1 in seconds

Returned:
tt1,tt2    double    TT as a 2-part Julian Date

Returned (function value):
int       status:  0 = OK

Notes:

1) ut11+ut12 is Julian Date, apportioned in any convenient way
between the two arguments, for example where ut11 is the Julian
Day Number and ut12 is the fraction of a day.  The returned
tt1,tt2 follow suit.

2) The argument dt is classical Delta T.

Reference:

Explanatory Supplement to the Astronomical Almanac,
P. Kenneth Seidelmann (ed), University Science Books (1992)

This revision:  2013 June 18

SOFA release 2015-02-09

Copyright (C) 2015 IAU SOFA Board.  See notes at end.
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