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Manual Reference Pages  - d2b (3m_time)

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NAME

d2b(3f) - [M_time:BAS] given DAT date-time array returns Baseday and Seconds type (LICENSE:MIT)

CONTENTS

Synopsis
Description
Options
Returns
Example
Author
License

SYNOPSIS

function d2b(dat) result(bas)

    integer,intent(in)  :: dat(8)
    type(BAStime) :: bas

DESCRIPTION

Given DAT date-time array returns Baseday and Seconds type

OPTIONS

dat	Integer array holding a "DAT" array, similar in structure to the array returned by the intrinsic DATE_AND_TIME(3f):

             dat=[ year,month,day,timezone,hour,&
             & minutes,seconds,milliseconds]

If not present, use current time.

RETURNS

bas	A Baseday and seconds(MJD) is composed of whole days since the start of 17 Nov 1858 CE in Universal Time (UTC) and an offset in seconds from the base day.

EXAMPLE

Sample program:

    program demo_d2b
    use M_time, only : d2b, BAStime, d2j, d2m
    implicit none
    integer :: dat(8)
    type(BAStime) :: bas
    !                            Modified Julian Dates
    !
    !   To use this table, add the day-of-month to the tabulated entry.
    !   For example, 30 Jan 2000 = MJD 51573.
    ! __________________________________________________________________
    !  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009
    integer,parameter :: array(1:12,2000:2009)=reshape([ &
     51543,51909,52274,52639,53004,53370,53735,54100,54465,54831, & ! Jan
     51574,51940,52305,52670,53035,53401,53766,54131,54496,54862, & ! Feb
     51603,51968,52333,52698,53064,53429,53794,54159,54525,54890, & ! Mar
     51634,51999,52364,52729,53095,53460,53825,54190,54556,54921, & ! Apr
     51664,52029,52394,52759,53125,53490,53855,54220,54586,54951, & ! May
     51695,52060,52425,52790,53156,53521,53886,54251,54617,54982, & ! Jun
     51725,52090,52455,52820,53186,53551,53916,54281,54647,55012, & ! Jul
     51756,52121,52486,52851,53217,53582,53947,54312,54678,55043, & ! Aug
     51787,52152,52517,52882,53248,53613,53978,54343,54709,55074, & ! Sep
     51817,52182,52547,52912,53278,53643,54008,54373,54739,55104, & ! Oct
     51848,52213,52578,52943,53309,53674,54039,54404,54770,55135, & ! Nov
     51878,52243,52608,52973,53339,53704,54069,54434,54800,55165],& ! Dec
     shape=shape(array),order=[2,1])
     integer :: i,j
       call date_and_time(values=dat)
       write(*,’(" Today is:",*(i0:,":"))’)dat
       bas=d2b(dat)
       write(*,*)’Baseday and Seconds is’,bas
       write(*,*)’Baseday is’, bas%base_day ! whole days since the MJD Epoch date
       write(*,*)’Seconds is’, bas%secs     ! offset in seconds from start of BASE_DAY
       ! print any date that does not match regression test values
       do i=2000,2009
        do j=1,12
         !dat=[ year,month,day,timezone,hour,minutes,seconds,milliseconds]
         dat=[i,j,1,0,0,0,0,0]   ! first day of month
         bas=d2b(dat)
         if(array(j,i)+1.ne.bas%base_day)then
            write(*,*)i,j,array(j,i)+1,d2b(dat),d2m(dat),d2j(dat)-2400000.5
         endif
        enddo
       enddo
    end program demo_d2b

‘‘‘ Results: ‘‘‘text

>	Today is:2025:3:28:-240:12:8:0:42 > Baseday and Seconds is 60762 58080.042001605034 > Baseday is 60762 > Seconds is 58080.042001605034

AUTHOR

John S. Urban, 2025

LICENSE

    MIT

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