function DCCalDateDifference1( start_date, end_date, cal ) result(sec)
!
! 日時差を算出します.
!
! 省略可能引数 *cal* が省略された場合には, 日時差の算出に
! dc_calendar 内部で保持される暦が用いられます.
! *cal* が省略されない場合にはその変数に設定された暦が用いられます.
!
! Evaluate difference of date.
!
! If an optional argument *cal* is omitted,
! information of calendar that is stored in the "dc_calendar"
! is used for evaluation of difference of date.
! If *cal* is not omitted, information of the variable is used.
!
use dc_calendar_internal, only: default_cal, default_cal_set, dccaltype_str, dccaldate_str2usym
use dc_calendar_types, only: DC_CAL, DC_CAL_DATE, UNIT_SYMBOL_YEAR, UNIT_SYMBOL_MONTH, UNIT_SYMBOL_DAY, UNIT_SYMBOL_HOUR, UNIT_SYMBOL_MIN, UNIT_SYMBOL_SEC, CAL_USER_DEFINED, CAL_CYCLIC, CAL_NOLEAP, CAL_JULIAN, CAL_GREGORIAN, CAL_360DAY
use dc_error, only: StoreError, DC_NOERR, DC_EBADUNIT, DC_ENOTINIT
use dc_message, only: MessageNotify
use dc_trace, only: BeginSub, EndSub
use dc_types, only: DP, TOKEN, STRING
implicit none
real(DP):: sec
! *start_date* と *end_date* との差 (秒数).
! Difference (seconds) between *start_date* and *end_date*.
type(DC_CAL_DATE), intent(in):: start_date
! 起点となる日時.
! Date of origin.
type(DC_CAL_DATE), intent(in):: end_date
! 終点となる日時.
! Date of terminus.
type(DC_CAL), intent(in), optional, target:: cal
! 暦情報を収めたオブジェクト.
!
! An object that stores information of
! calendar.
! 作業変数
! Work variables
!
type(DC_CAL), pointer:: calp =>null()
real(DP):: start_year, start_day, start_sec, start_neg_offset_day
real(DP):: end_year, end_day, end_sec, end_neg_offset_day
integer:: day_in_4years, day_in_400years
integer:: start_year_int, end_year_int
integer:: i, j
character(*), parameter:: subname = 'DCCalDateDifference1'
continue
! オブジェクトのポインタ割付
! Associate pointer of an object
!
if ( present( cal ) ) then
calp => cal
else
calp => default_cal
if ( .not. calp % initialized ) call default_cal_set
end if
! 初期設定のチェック
! Check initialization
!
if ( .not. calp % initialized ) then
sec = 0.0_DP
return
end if
if ( .not. start_date % initialized ) then
sec = 0.0_DP
return
end if
if ( .not. end_date % initialized ) then
sec = 0.0_DP
return
end if
start_neg_offset_day = 0
end_neg_offset_day = 0
start_year_int = start_date % year
end_year_int = end_date % year
! 日への変換
! Convert into days
!
select case( calp % cal_type )
case( CAL_JULIAN )
day_in_4years = 1461
! 年が負の場合，400 年単位で引き算し下駄を履かせる
!
do while ( start_year_int < 1 )
start_neg_offset_day = start_neg_offset_day + day_in_4years * 100
start_year_int = start_year_int + 400
end do
! start_date の日への変換
! Convert start_date into days
!
if ( ( start_year_int - 1 ) > 4 ) then
start_day = int( ( start_year_int - 1 ) / 4 ) * day_in_4years
start_year = mod( start_year_int - 1, 4 ) + 1
else
start_day = 0
start_year = start_year_int
end if
start_day = start_day + ( start_year - 1 ) * sum ( calp % day_in_month(:) )
do i = 1, start_date % month - 1
if ( start_year == 4 .and. i == 2 ) then
start_day = start_day + 29
else
start_day = start_day + calp % day_in_month(i)
end if
end do
start_day = start_day + start_date % day
! 年が負の場合，400 年単位で引き算し下駄を履かせる
!
do while ( end_year_int < 1 )
end_neg_offset_day = end_neg_offset_day + day_in_4years * 100
end_year_int = end_year_int + 400
end do
! end_date の日への変換
! Convert end_date into days
!
if ( ( end_year_int - 1 ) > 4 ) then
end_day = int( ( end_year_int - 1 ) / 4 ) * day_in_4years
end_year = mod( end_year_int - 1, 4 ) + 1
else
end_day = 0
end_year = end_year_int
end if
end_day = end_day + ( end_year - 1 ) * sum ( calp % day_in_month(:) )
do i = 1, end_date % month - 1
if ( end_year == 4 .and. i == 2 ) then
end_day = end_day + 29
else
end_day = end_day + calp % day_in_month(i)
end if
end do
end_day = end_day + end_date % day
case( CAL_GREGORIAN )
day_in_400years = 146097
! 年が負の場合，400 年単位で引き算し下駄を履かせる
!
do while ( start_year_int < 1 )
start_neg_offset_day = start_neg_offset_day + day_in_400years
start_year_int = start_year_int + 400
end do
! start_date の日への変換
! Convert start_date into days
!
if ( ( start_year_int - 1 ) > 400 ) then
start_day = int( ( start_year_int - 1 ) / 400 ) * day_in_400years
start_year = mod( start_year_int - 1, 400 ) + 1
else
start_day = 0
start_year = start_year_int
end if
do j = 1, int( start_year - 1 )
do i = 1, calp % month_in_year
if ( i == 2 ) then
if ( mod( j, 400 ) == 0 ) then
start_day = start_day + 29
elseif ( mod( j, 100 ) == 0 ) then
start_day = start_day + 28
elseif ( mod( j, 4 ) == 0 ) then
start_day = start_day + 29
else
start_day = start_day + 28
end if
else
start_day = start_day + calp % day_in_month(i)
end if
end do
end do
do i = 1, start_date % month - 1
if ( i == 2 ) then
if ( mod( start_year, 400.0_DP ) == 0 ) then
start_day = start_day + 29
elseif ( mod( start_year, 100.0_DP ) == 0 ) then
start_day = start_day + 28
elseif ( mod( start_year, 4.0_DP ) == 0 ) then
start_day = start_day + 29
else
start_day = start_day + 28
end if
else
start_day = start_day + calp % day_in_month(i)
end if
end do
start_day = start_day + start_date % day
! 年が負の場合，400 年単位で引き算し下駄を履かせる
!
do while ( end_year_int < 1 )
end_neg_offset_day = end_neg_offset_day + day_in_400years
end_year_int = end_year_int + 400
end do
! end_date の日への変換
! Convert end_date into days
!
if ( ( end_year_int - 1 ) > 400 ) then
end_day = int( ( end_year_int - 1 ) / 400 ) * day_in_400years
end_year = mod( end_year_int - 1, 400 ) + 1
else
end_day = 0
end_year = end_year_int
end if
do j = 1, int( end_year - 1 )
do i = 1, calp % month_in_year
if ( i == 2 ) then
if ( mod( j, 400 ) == 0 ) then
end_day = end_day + 29
elseif ( mod( j, 100 ) == 0 ) then
end_day = end_day + 28
elseif ( mod( j, 4 ) == 0 ) then
end_day = end_day + 29
else
end_day = end_day + 28
end if
else
end_day = end_day + calp % day_in_month(i)
end if
end do
end do
do i = 1, end_date % month - 1
if ( i == 2 ) then
if ( mod( end_year, 400.0_DP ) == 0 ) then
end_day = end_day + 29
elseif ( mod( end_year, 100.0_DP ) == 0 ) then
end_day = end_day + 28
elseif ( mod( end_year, 4.0_DP ) == 0 ) then
end_day = end_day + 29
else
end_day = end_day + 28
end if
else
end_day = end_day + calp % day_in_month(i)
end if
end do
end_day = end_day + end_date % day
case default
! start_date の日への変換
! Convert start_date into days
!
start_day = ( start_year_int - 1 ) * sum ( calp % day_in_month(:) )
do i = 1, start_date % month - 1
start_day = start_day + calp % day_in_month(i)
end do
start_day = start_day + start_date % day
! end_date の日への変換
! Convert end_date into days
!
end_day = ( end_year_int - 1 ) * sum ( calp % day_in_month(:) )
do i = 1, end_date % month - 1
end_day = end_day + calp % day_in_month(i)
end do
end_day = end_day + end_date % day
end select
! start_date の秒への変換
! Convert start_date into seconds
!
start_sec = ( start_day - 1 - start_neg_offset_day ) * calp % hour_in_day * calp % min_in_hour * calp % sec_in_min + start_date % hour * calp % min_in_hour * calp % sec_in_min + start_date % min * calp % sec_in_min + start_date % sec
! end_date の秒への変換
! Convert end_date into seconds
!
end_sec = ( end_day - 1 - end_neg_offset_day ) * calp % hour_in_day * calp % min_in_hour * calp % sec_in_min + end_date % hour * calp % min_in_hour * calp % sec_in_min + end_date % min * calp % sec_in_min + end_date % sec
! 差分の計算
! Calculate difference
!
sec = end_sec - start_sec
! 終了処理, 例外処理
! Termination and Exception handling
!
999 continue
nullify( calp )
end function DCCalDateDifference1