pkg/cal/cal_stepsforday.F

C $Header: /u/gcmpack/development/heimbach/ecco_env/pkg/cal/cal_stepsforday.F,v 1.4 2001/02/02 16:57:22 heimbach Exp $

#include "CAL_CPPOPTIONS.h"

      subroutine cal_StepsForDay(
     I                            iday,
     O                            firststep,
     O                            laststep,
     O                            nsteps,
     I                            mythid
     &                          )

c     ==================================================================
c     SUBROUTINE cal_StepsForDay
c     ==================================================================
c
c     o Given the current day of the integration this routine returns
c       first, the last and the number of model steps the will have to
c       be performed.
c
c       This routine also checks consistency of variables quite
c       extensively.
c
c     started: Christian Eckert eckert@mit.edu  06-Apr-2000
c
c     changed: 
c
c     ==================================================================
c     SUBROUTINE cal_StepsForDay
c     ==================================================================

      implicit none

c     == global variables ==

#include "cal.h"

c     == routine arguments ==

      integer iday
      integer firststep
      integer laststep
      integer nsteps
      integer mythid

c     == local variables ==

      integer ierr
      integer mdstep
      integer numdays
      integer numsteps
      integer frac1
      integer frac2
      integer frac3
      integer frac4
      integer fullsteps
      integer firstyear
      integer firstmonth
      integer firstday
      integer lyfirst
      integer startsecs
      integer lastday
      integer endsecs

c     == external ==

      external cal_IntDays
      integer  cal_IntDays
      external cal_IsLeap
      integer  cal_IsLeap

c     == end of interface ==

      numdays    = cal_IntDays( mythid )
      lyfirst    = cal_IsLeap( firstyear, mythid )

      mdstep     = int(modelstep)

      firstyear  = modelstartdate(1)/10000
      firstmonth = mod(modelstartdate(1)/100,100)
      firstday   = mod(modelstartdate(1),100)
      lastday    = mod(modelenddate(1),100)

      startsecs  = (modelstartdate(2)/10000)*secondsperhour +
     &             mod(modelstartdate(2)/100,100)*secondsperminute +
     &             mod(modelstartdate(2),100)
      endsecs    = (modelenddate(2)/10000)*secondsperhour +
     &             mod(modelenddate(2)/100,100)*secondsperminute +
     &             mod(modelenddate(2),100)

      if ( numdays .eq. 1 ) then
        if ( iday .eq. firstday ) then
c--       Get the number of steps in the first day.
          if ( firstday .eq. lastday ) then
            firststep = 1
            laststep  = modelintsteps
          else if ( mod(firstday+1,ndaymonth(firstmonth,lyfirst)) .eq.
     &              lastday ) then
c--         This can only happen if we end at midnight of the next day.
            if ( modelenddate(2) .eq. 0 ) then
              firststep = 1
              laststep  = modelintsteps
c--           Note: This holds only if modelenddate was determined
c--                 such that it coincides with the model's final time.
            else
c--           We do not end at midnight of the first day of
c--           the next month.
              ierr = 2604
              call cal_PrintError( ierr, mythid )
              stop ' stopped in cal_StepsForDay.'
            endif
          else
c--         The first and the last day are inconsistent with iday.
            ierr = 2603
            call cal_PrintError( ierr, mythid )
            stop ' stopped in cal_StepsForDay.'
          endif
        else
c--       The variables numdays and iday are inconsistent;
c--       ( iday .gt. numdays ).
          ierr = 2602
          call cal_PrintError( ierr, mythid )
          stop ' stopped in cal_StepsForDay.'
        endif

      else if ( numdays .gt. 1 ) then
c--     More than one day of integration.
        if ( iday .eq. 1 ) then
          firststep = 1
          laststep  = int((secondsperday - startsecs)/mdstep)
        else if ( ( iday .gt. 1      ) .and.
     &            ( iday .lt. numdays) ) then
c--       Somewhere between first and last month.
c--       The first steps in iday.
          fullsteps = int((secondsperday - startsecs)/mdstep)
          numsteps  = fullsteps
c--       What's left in the first day (frac1).
          frac1     = (secondsperday - startsecs) - fullsteps*mdstep
          fullsteps = int(secondsperday/modelstep)
c--       What's left in a complete day (frac2).
          frac2     = secondsperday - fullsteps*mdstep
c--       What's left up to the current day (frac3).
          frac3     = frac1 + frac2*(iday - 1)
          numsteps  = numsteps + (iday - 1)*fullsteps +
     &                frac3/mdstep
          laststep  = numsteps
          firststep = laststep - secondsperday/mdstep + 1

        else if ( iday .eq. numdays ) then
c--       The last day of integration.
c--       The first step in iday.
          fullsteps = int((secondsperday - startsecs)/mdstep)
          numsteps  = fullsteps
c--       What's left in the first day (frac1).
          frac1     = (secondsperday - startsecs) - fullsteps*mdstep
          fullsteps = int(secondsperday/modelstep)
c--       What's left in a complete day (frac2).
          frac2     = secondsperday - fullsteps*mdstep
c--       What's left up to the day before the last (frac3).
          frac3     = frac1 + frac2*(iday - 2)
          numsteps  = numsteps + (iday - 2)*fullsteps
c--       The last step in iday.
          if ( modelenddate(2) .eq. 0 ) then
c--         This can only happen if we end at midnight of the next day.
            laststep  = numsteps + fullsteps
            firststep = numsteps + 1
c--         Note: There should be no fraction left
c--               ( mod(frac3,mdstep) = frac3/mdstep ) if modelenddate
c--               is based on an integral number of timesteps.
          else
            frac4     = frac3 + endsecs
            numsteps  = numsteps + frac4/mdstep
            laststep  = numsteps

c--         Note: There should be no fraction left
c--               ( mod(frac4,mdstep = frac4/mdstep ) if modelenddate
c--               is based on an integral number of timesteps.

            firststep = laststep - endsecs/mdstep + 1
          endif
        else
c--       The variables iday and numdays are inconsistent.
          ierr = 2605
          call cal_PrintError( ierr, mythid )
          stop ' stopped in cal_DaysForMonth.'
        endif
      else
c--     The number of days to integrate is wrong; check cal_IntDays.
        ierr = 2601
        call cal_PrintError( ierr, mythid )
        stop ' stopped in cal_StepsForDay.'
      endif

c--   The number of days to integrate in the given month.
      nsteps = laststep - firststep + 1

      return
      end

1	heimbach	1.1	C $Header: /u/gcmpack/development/heimbach/ecco_env/pkg/cal/cal_stepsforday.F,v 1.4 2001/02/02 16:57:22 heimbach Exp $
2
3			#include "CAL_CPPOPTIONS.h"
4
5			subroutine cal_StepsForDay(
6			I iday,
7			O firststep,
8			O laststep,
9			O nsteps,
10			I mythid
11			& )
12
13			c ==================================================================
14			c SUBROUTINE cal_StepsForDay
15			c ==================================================================
16			c
17			c o Given the current day of the integration this routine returns
18			c first, the last and the number of model steps the will have to
19			c be performed.
20			c
21			c This routine also checks consistency of variables quite
22			c extensively.
23			c
24			c started: Christian Eckert eckert@mit.edu 06-Apr-2000
25			c
26			c changed:
27			c
28			c ==================================================================
29			c SUBROUTINE cal_StepsForDay
30			c ==================================================================
31
32			implicit none
33
34			c == global variables ==
35
36			#include "cal.h"
37
38			c == routine arguments ==
39
40			integer iday
41			integer firststep
42			integer laststep
43			integer nsteps
44			integer mythid
45
46			c == local variables ==
47
48			integer ierr
49			integer mdstep
50			integer numdays
51			integer numsteps
52			integer frac1
53			integer frac2
54			integer frac3
55			integer frac4
56			integer fullsteps
57			integer firstyear
58			integer firstmonth
59			integer firstday
60			integer lyfirst
61			integer startsecs
62			integer lastday
63			integer endsecs
64
65			c == external ==
66
67			external cal_IntDays
68			integer cal_IntDays
69			external cal_IsLeap
70			integer cal_IsLeap
71
72			c == end of interface ==
73
74			numdays = cal_IntDays( mythid )
75			lyfirst = cal_IsLeap( firstyear, mythid )
76
77			mdstep = int(modelstep)
78
79			firstyear = modelstartdate(1)/10000
80			firstmonth = mod(modelstartdate(1)/100,100)
81			firstday = mod(modelstartdate(1),100)
82			lastday = mod(modelenddate(1),100)
83
84			startsecs = (modelstartdate(2)/10000)*secondsperhour +
85			& mod(modelstartdate(2)/100,100)*secondsperminute +
86			& mod(modelstartdate(2),100)
87			endsecs = (modelenddate(2)/10000)*secondsperhour +
88			& mod(modelenddate(2)/100,100)*secondsperminute +
89			& mod(modelenddate(2),100)
90
91			if ( numdays .eq. 1 ) then
92			if ( iday .eq. firstday ) then
93			c-- Get the number of steps in the first day.
94			if ( firstday .eq. lastday ) then
95			firststep = 1
96			laststep = modelintsteps
97			else if ( mod(firstday+1,ndaymonth(firstmonth,lyfirst)) .eq.
98			& lastday ) then
99			c-- This can only happen if we end at midnight of the next day.
100			if ( modelenddate(2) .eq. 0 ) then
101			firststep = 1
102			laststep = modelintsteps
103			c-- Note: This holds only if modelenddate was determined
104			c-- such that it coincides with the model's final time.
105			else
106			c-- We do not end at midnight of the first day of
107			c-- the next month.
108			ierr = 2604
109			call cal_PrintError( ierr, mythid )
110			stop ' stopped in cal_StepsForDay.'
111			endif
112			else
113			c-- The first and the last day are inconsistent with iday.
114			ierr = 2603
115			call cal_PrintError( ierr, mythid )
116			stop ' stopped in cal_StepsForDay.'
117			endif
118			else
119			c-- The variables numdays and iday are inconsistent;
120			c-- ( iday .gt. numdays ).
121			ierr = 2602
122			call cal_PrintError( ierr, mythid )
123			stop ' stopped in cal_StepsForDay.'
124			endif
125
126			else if ( numdays .gt. 1 ) then
127			c-- More than one day of integration.
128			if ( iday .eq. 1 ) then
129			firststep = 1
130			laststep = int((secondsperday - startsecs)/mdstep)
131			else if ( ( iday .gt. 1 ) .and.
132			& ( iday .lt. numdays) ) then
133			c-- Somewhere between first and last month.
134			c-- The first steps in iday.
135			fullsteps = int((secondsperday - startsecs)/mdstep)
136			numsteps = fullsteps
137			c-- What's left in the first day (frac1).
138			frac1 = (secondsperday - startsecs) - fullsteps*mdstep
139			fullsteps = int(secondsperday/modelstep)
140			c-- What's left in a complete day (frac2).
141			frac2 = secondsperday - fullsteps*mdstep
142			c-- What's left up to the current day (frac3).
143			frac3 = frac1 + frac2*(iday - 1)
144			numsteps = numsteps + (iday - 1)*fullsteps +
145			& frac3/mdstep
146			laststep = numsteps
147			firststep = laststep - secondsperday/mdstep + 1
148
149			else if ( iday .eq. numdays ) then
150			c-- The last day of integration.
151			c-- The first step in iday.
152			fullsteps = int((secondsperday - startsecs)/mdstep)
153			numsteps = fullsteps
154			c-- What's left in the first day (frac1).
155			frac1 = (secondsperday - startsecs) - fullsteps*mdstep
156			fullsteps = int(secondsperday/modelstep)
157			c-- What's left in a complete day (frac2).
158			frac2 = secondsperday - fullsteps*mdstep
159			c-- What's left up to the day before the last (frac3).
160			frac3 = frac1 + frac2*(iday - 2)
161			numsteps = numsteps + (iday - 2)*fullsteps
162			c-- The last step in iday.
163			if ( modelenddate(2) .eq. 0 ) then
164			c-- This can only happen if we end at midnight of the next day.
165			laststep = numsteps + fullsteps
166			firststep = numsteps + 1
167			c-- Note: There should be no fraction left
168			c-- ( mod(frac3,mdstep) = frac3/mdstep ) if modelenddate
169			c-- is based on an integral number of timesteps.
170			else
171			frac4 = frac3 + endsecs
172			numsteps = numsteps + frac4/mdstep
173			laststep = numsteps
174
175			c-- Note: There should be no fraction left
176			c-- ( mod(frac4,mdstep = frac4/mdstep ) if modelenddate
177			c-- is based on an integral number of timesteps.
178
179			firststep = laststep - endsecs/mdstep + 1
180			endif
181			else
182			c-- The variables iday and numdays are inconsistent.
183			ierr = 2605
184			call cal_PrintError( ierr, mythid )
185			stop ' stopped in cal_DaysForMonth.'
186			endif
187			else
188			c-- The number of days to integrate is wrong; check cal_IntDays.
189			ierr = 2601
190			call cal_PrintError( ierr, mythid )
191			stop ' stopped in cal_StepsForDay.'
192			endif
193
194			c-- The number of days to integrate in the given month.
195			nsteps = laststep - firststep + 1
196
197			return
198			end
199