Under construction.
!= Sample program for gtool_history/gtool5
!
! * 2009/02/28 Y.Morikawa
! * 2007/06/25 M.Odaka
! * 2006/10/25 Y.Morikawa
! * 2003/08/21 M.Odaka
! * 2001/02/27 S.Takehiro
!
! Solving diffusion equation
! \[
! du/dt = \kappa d^2 u/dx^2
! \]
! for giving values of $u$ at $x=[0,1]$.
!
program diffusion_date
use gtool_history ! Access module (モジュール指定)
use dc_date ! Access module (モジュール指定)
use dc_types ! Access module (モジュール指定)
integer, parameter :: nx=30 ! Grid number (グリッド数)
real(DP), parameter :: dx=1.0/(nx-1) ! Grid interval (グリッド間隔)
real(DP), parameter :: dt=1. ! Time step [s] (時間間隔 [秒])
type(DC_DIFFTIME) :: deltime ! Time step (時間間隔)
type(DC_DIFFTIME) :: endtime ! End time (終了時刻)
type(DC_DIFFTIME) :: dsptime ! Output interval (出力間隔)
type(DC_DIFFTIME) :: curtime ! Current time (現在時刻)
real(DP), dimension(nx):: x=(/(dx*(i-1),i=1,nx)/) ! X coordinate (座標変数)
real(DP), dimension(nx):: temp ! Temperature (温度)
real(DP), parameter :: kappa=0.0001 ! Diffusion coefficient (熱拡散係数)
type(DC_DATETIME):: date ! Date (日時)
character(256):: date_str
call DCDateTimeCreate(date, year=2009, mon=2, day=28, hour=23, min=59)
! Set date
! (日時設定)
call DCDiffTimeCreate(curtime, 0., 'sec') ! Set initial time
! (初期時刻設定)
call DCDiffTimeCreate(deltime, dt, 'sec') ! Set time step
! (時間間隔設定)
call DCDiffTimeCreate(endtime, 10., 'min') ! Set end time
! (終了時刻設定)
call DCDiffTimeCreate(dsptime, 0.1, 'min') ! Set output interval
! (出力間隔設定)
temp = exp(-((x-0.5)/0.1)**2) ! Set initial value
! (初期値設定)
call HistoryCreate( & ! Create output file
& file='diffusion_date.nc', & ! (ヒストリー作成)
& title='Diffusion equation', &
& source='Sample program of gtool_history/gtool5', &
& institution='GFD_Dennou Club davis project', &
& dims=(/'x','t'/), dimsizes=(/nx,0/), &
& longnames=(/'X-coordinate','time '/), &
& units=(/'m ','min'/), &
& origin=curtime, interval=dsptime )
call HistoryPut('x',x) ! Output 'x' (次元変数出力)
call HistoryAddVariable( & ! Set output variable
& varname='temp', dims=(/'x','t'/), & ! (変数定義)
& longname='temperature', units='K', xtype='double')
call HistoryAddAttr('temp','gt_graph_tick_all',1)
call HistoryAddAttr('temp','gt_graph_contour_spacing',(/0.0,1.0,0.01/))
call HistoryAddAttr('temp','+gt_user_davis_kappa',kappa)
call HistoryPut('temp',temp) ! Output 'temp' (変数出力)
date_str = toChar(date)
write(6,*) "Start: ", trim(date_str) ! Display start date (開始日時出力)
do while ( curtime <= endtime ) ! Check termination (終了判定)
temp(2:nx-1) = temp(2:nx-1) & ! Time integration (時間積分)
& + kappa*(temp(3:nx)-2*temp(2:nx-1)+temp(1:nx-2))/dx**2*dt
if ( mod( curtime, dsptime ) == 0 ) then ! Check output timing (出力タイミング判定)
call HistoryPut('temp',temp) ! Output 'temp' (変数出力)
endif
curtime = curtime + deltime ! Progress model time (モデル時刻進行)
enddo
date = date + curtime ! Evaluate end date (終了日時算出)
date_str = toChar(date) ! Convert date into characters (日時を文字型変数へ変換)
write(6,*) "End: ", trim(date_str) ! Display end date (終了日時出力)
call HistoryClose
stop
end program diffusion_date
