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|
! Sample plots using date / time formatting for axes
!
! Copyright (C) 2008 Andrew Ross
! Copyright (C) 2008-2016 Alan W. Irwin
!
! This file is part of PLplot.
!
! PLplot is free software; you can redistribute it and/or modify
! it under the terms of the GNU Library General Public License as
! published by the Free Software Foundation; either version 2 of the
! License, or (at your option) any later version.
!
! PLplot is distributed in the hope that it will be useful,
! but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
! GNU Library General Public License for more details.
!
! You should have received a copy of the GNU Library General Public
! License along with PLplot; if not, write to the Free Software
! Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
!
! N.B. the pl_test_flt parameter used in this code is only
! provided by the plplot module to allow convenient developer
! testing of either kind(1.0) or kind(1.0d0) floating-point
! precision regardless of the floating-point precision of the
! PLplot C libraries. We do not guarantee the value of this test
! parameter so it should not be used by users, and instead user
! code should replace the pl_test_flt parameter by whatever
! kind(1.0) or kind(1.0d0) precision is most convenient for them.
! For further details on floating-point precision issues please
! consult README_precision in this directory.
!
program x29f
use plplot
implicit none
integer, parameter :: double = kind(1.0d0)
integer :: plparseopts_rc
real(kind=double), parameter :: PI = PL_PI
real(kind=pl_test_flt), dimension(365) :: x, y, xerr1, xerr2, yerr1, yerr2
plparseopts_rc = plparseopts(PL_PARSE_FULL)
if(plparseopts_rc .ne. 0) stop "plparseopts error"
call plinit()
! This is the ASCII value for character @
call plsesc(64)
call plot1()
call plot2()
call plot3()
call plot4()
call plend()
contains
!====================================================================
!
! Plot a model diurnal cycle of temperature
subroutine plot1()
integer :: i, npts
real(kind=pl_test_flt) :: xmin, xmax, ymin, ymax
parameter(npts = 73)
parameter(xmin = 0.0_pl_test_flt)
parameter(xmax = 60.0_pl_test_flt*60.0_pl_test_flt*24.0_pl_test_flt)
parameter(ymin = 10.0_pl_test_flt)
parameter(ymax = 20.0_pl_test_flt)
do i = 1,npts
x(i) = xmax*(real(i-1,kind=pl_test_flt)/real(npts,kind=pl_test_flt))
y(i) = 15.0_pl_test_flt - 5.0_pl_test_flt* &
cos(2.0_pl_test_flt*PI*real(i-1,kind=pl_test_flt)/ &
real(npts,kind=pl_test_flt))
! Set x error bars to +/- 5 minute
xerr1(i) = x(i)-60.0_pl_test_flt*5.0_pl_test_flt
xerr2(i) = x(i)+60.0_pl_test_flt*5.0_pl_test_flt
! Set y error bars to +/- 0.1 deg C
yerr1(i) = y(i)-0.1_pl_test_flt
yerr2(i) = y(i)+0.1_pl_test_flt
enddo
call pladv(0)
! Rescale major ticks marks by 0.5
call plsmaj(0.0_pl_test_flt,0.5_pl_test_flt)
! Rescale minor ticks and error bar marks by 0.5
call plsmin(0.0_pl_test_flt,0.5_pl_test_flt)
call plvsta()
call plwind(xmin, xmax, ymin, ymax)
! Draw a box with ticks spaced every 3 hour in X and 1 degree C in Y.
call plcol0(1)
! Set time format to be hours:minutes
call pltimefmt("%H:%M")
call plbox("bcnstd", 3.0_pl_test_flt*60.0_pl_test_flt*60.0_pl_test_flt, 3, "bcnstv", &
1.0_pl_test_flt, 5)
call plcol0(3)
call pllab("Time (hours:mins)", "Temperature (degC)", &
"@frPLplot Example 29 - Daily temperature")
call plcol0(4)
call plline(x(1:npts), y(1:npts))
call plcol0(2)
call plerrx(xerr1(1:npts), xerr2(1:npts), y(1:npts))
call plcol0(3)
call plerry(x(1:npts), yerr1(1:npts), yerr2(1:npts))
! Rescale major / minor tick marks back to default
call plsmin(0.0_pl_test_flt,1.0_pl_test_flt)
call plsmaj(0.0_pl_test_flt,1.0_pl_test_flt)
end subroutine plot1
!
! Plot the number of hours of daylight as a function of day for a year
!
subroutine plot2()
integer :: j, npts
real(kind=pl_test_flt) :: xmin, xmax, ymin, ymax
real(kind=pl_test_flt) :: lat, p, d
! Latitude for London
parameter (lat = 51.5_pl_test_flt)
parameter (npts = 365)
parameter(xmin = 0.0_pl_test_flt)
parameter(xmax = npts*60.0_pl_test_flt*60.0_pl_test_flt*24.0_pl_test_flt)
parameter(ymin = 0)
parameter(ymax = 24)
! Formula for hours of daylight from
! "A Model Comparison for Daylength as a Function of Latitude and
! Day of the Year", 1995, Ecological Modelling, 80, pp 87-95.
do j=1,npts
x(j) = (j-1)*60.0_pl_test_flt*60.0_pl_test_flt*24.0_pl_test_flt
p = asin(0.39795_pl_test_flt*cos(0.2163108_pl_test_flt + 2.0_pl_test_flt* &
atan(0.9671396_pl_test_flt*tan(0.00860_pl_test_flt*(j-187)))))
d = 24.0_pl_test_flt - (24.0_pl_test_flt/PI)* &
acos( (sin(0.8333_pl_test_flt*PI/180.0_pl_test_flt) + &
sin(lat*PI/180.0_pl_test_flt)*sin(p)) / (cos(lat*PI/180.0_pl_test_flt)* &
cos(p)) )
y(j) = d
enddo
call plcol0(1)
! Set time format to be abbreviated month name followed by day of month
call pltimefmt("%b %d")
call plprec(1,1)
call plenv(xmin, xmax, ymin, ymax, 0, 40)
call plcol0(3)
call pllab("Date", "Hours of daylight", &
"@frPLplot Example 29 - Hours of daylight at 51.5N")
call plcol0(4)
call plline(x, y)
call plprec(0,0)
end subroutine plot2
!
!
!
subroutine plot3()
integer :: i, npts
real(kind=pl_test_flt) :: xmin, xmax, ymin, ymax
integer :: tstart
parameter (npts = 62)
! number of seconds elapsed since the Unix epoch (1970-01-01, UTC) for
! 2005-12-01, UTC. This is the same result as the Python
! calendar.timegm((2005,12,1,0,0,0)) result or the Linux C timegm
! result corresponding to 2005-12-01.
tstart = 1133395200
xmin = real(tstart,kind=pl_test_flt)
xmax = xmin + npts*60.0_pl_test_flt*60.0_pl_test_flt*24.0_pl_test_flt
ymin = 0.0_pl_test_flt
ymax = 5.0_pl_test_flt
do i=1,npts
x(i) = xmin + real(i-1,kind=pl_test_flt)*60.0_pl_test_flt*60.0_pl_test_flt*24.0_pl_test_flt
y(i) = 1.0_pl_test_flt + &
sin( 2.0_pl_test_flt*PI*real(i-1,kind=pl_test_flt)/7.0_pl_test_flt) + &
exp( real(min(i-1,npts+1-i),kind=pl_test_flt) / 31.0_pl_test_flt)
enddo
call pladv(0)
call plvsta()
call plwind(xmin, xmax, ymin, ymax)
call plcol0(1)
! Set time format to be ISO 8601 standard YYYY-MM-DD. Note that this is
! equivalent to %f for C99 compliant implementations of strftime.
call pltimefmt("%Y-%m-%d")
! Draw a box with ticks spaced every 14 days in X and 1 hour in Y.
call plbox("bcnstd", 14.0_pl_test_flt*24.0_pl_test_flt*60.0_pl_test_flt*60.0_pl_test_flt,14, &
"bcnstv", 1.0_pl_test_flt, 4)
call plcol0(3)
call pllab("Date", "Hours of television watched", &
"@frPLplot Example 29 - Hours of television watched in " // &
"Dec 2005 / Jan 2006")
call plcol0(4)
call plssym(0.0_pl_test_flt, 0.5_pl_test_flt)
call plpoin(x(1:npts), y(1:npts), 2)
call plline(x(1:npts), y(1:npts))
end subroutine plot3
!
!
!
subroutine plot4()
! TAI-UTC (seconds) as a function of time.
real(kind=pl_test_flt) :: scale
real(kind=pl_test_flt) :: xmin, xmax, ymin, ymax, xlabel_step
integer :: k, npts = 0, i
logical :: if_TAI_time_format = .false.
character(len=10) :: time_format
character(len=100) :: title_suffix
character(len=100) :: xtitle
character(len=100) :: title
real(kind=pl_test_flt) :: x(1001), y(1001)
integer :: epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min
real(kind=pl_test_flt) :: epoch_sec
integer :: tai_year, tai_month, tai_day, tai_hour, tai_min
real(kind=pl_test_flt) :: tai_sec, tai
integer :: utc_year, utc_month, utc_day, utc_hour, utc_min
real(kind=pl_test_flt) :: utc_sec, utc
! Continuous time unit is Besselian years from whatever epoch is
! chosen below. Could change to seconds (or days) from the
! epoch, but then would have to adjust xlabel_step below.
scale = 365.242198781_pl_test_flt
! MJD epoch (see <https://en.wikipedia.org/wiki/Julian_day>).
! This is only set for illustrative purposes, and is overwritten
! below for the time-representation reasons given in the
! discussion below.
epoch_year = 1858
epoch_month = 11
epoch_day = 17
epoch_hour = 0
epoch_min = 0
epoch_sec = 0._pl_test_flt
! To illustrate the time-representation issues of using the
! MJD epoch, in 1985, MJD was roughly 46000 days which
! corresponds to 4e9 seconds. Thus, for the case where
! pl_test_flt corresponds to double precision which can
! represent continuous time to roughly 16 decimal digits of
! precision, the time-representation error is roughly ~400
! nanoseconds. Therefore the MJD epoch would be acceptable
! for the plots below when pl_test_flt corresponds to double
! precision. However, that epoch is obviously not acceptable
! for the case where pl_test_flt corresponds to single
! precision which can represent continuous time to only ~7
! decimal digits of precision corresponding to a time
! representation error of 400 seconds (!) in 1985. For this
! reason, we do not use the MJD epoch below and instead choose
! the best epoch for each case to minimize time-representation
! issues.
do k = 0,6
if (k .eq. 0) then
! Choose midpoint to maximize time-representation precision.
epoch_year = 1985
epoch_month = 0
epoch_day = 2
epoch_hour = 0
epoch_min = 0
epoch_sec = 0._pl_test_flt
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
call plctime(1950,0,2,0,0,0._pl_test_flt,xmin)
call plctime(2020,0,2,0,0,0._pl_test_flt,xmax)
npts = 70*12 + 1
ymin = 0.0_pl_test_flt
ymax = 36.0_pl_test_flt
time_format="%Y%"
if_TAI_time_format = .true.
title_suffix = "from 1950 to 2020"
xtitle = "Year"
xlabel_step = 10.0_pl_test_flt
elseif ((k .eq. 1) .or. (k .eq. 2)) then
! Choose midpoint to maximize time-representation precision.
epoch_year = 1961
epoch_month = 7
epoch_day = 1
epoch_hour = 0
epoch_min = 0
epoch_sec = 1.64757_pl_test_flt
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
call plctime(1961,7,1,0,0,1.64757_pl_test_flt-.20_pl_test_flt, xmin)
call plctime(1961,7,1,0,0,1.64757_pl_test_flt+.20_pl_test_flt, xmax)
npts = 1001
ymin = 1.625_pl_test_flt
ymax = 1.725_pl_test_flt
time_format = "%S%2%"
title_suffix = "near 1961-08-01 (TAI)"
xlabel_step = 0.05_pl_test_flt/(scale*86400.0_pl_test_flt)
if (k .eq. 1) then
if_TAI_time_format = .true.
xtitle = "Seconds (TAI)"
else
if_TAI_time_format = .false.
xtitle = "Seconds (TAI) labelled with corresponding UTC"
endif
elseif ((k .eq. 3) .or. (k .eq. 4)) then
! Choose midpoint to maximize time-representation precision.
epoch_year = 1963
epoch_month = 10
epoch_day = 1
epoch_hour = 0
epoch_min = 0
epoch_sec = 2.6972788_pl_test_flt
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
call plctime(1963,10,1,0,0,2.6972788_pl_test_flt-.20_pl_test_flt, xmin)
call plctime(1963,10,1,0,0,2.6972788_pl_test_flt+.20_pl_test_flt, xmax)
npts = 1001
ymin = 2.55_pl_test_flt
ymax = 2.75_pl_test_flt
time_format = "%S%2%"
title_suffix = "near 1963-11-01 (TAI)"
xlabel_step = 0.05_pl_test_flt/(scale*86400.0_pl_test_flt)
if (k .eq. 3) then
if_TAI_time_format = .true.
xtitle = "Seconds (TAI)"
else
if_TAI_time_format = .false.
xtitle = "Seconds (TAI) labelled with corresponding UTC"
endif
elseif ((k .eq. 5) .or. (k .eq. 6)) then
! Choose midpoint to maximize time-representation precision.
epoch_year = 2009
epoch_month = 0
epoch_day = 1
epoch_hour = 0
epoch_min = 0
epoch_sec = 34._pl_test_flt
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
call plctime(2009,0,1,0,0,34._pl_test_flt-5._pl_test_flt,xmin)
call plctime(2009,0,1,0,0,34._pl_test_flt+5._pl_test_flt,xmax)
npts = 1001
ymin = 32.5_pl_test_flt
ymax = 34.5_pl_test_flt
time_format = "%S%2%"
title_suffix = "near 2009-01-01 (TAI)"
xlabel_step = 1._pl_test_flt/(scale*86400._pl_test_flt)
if (k .eq. 5) then
if_TAI_time_format = .true.
xtitle = "Seconds (TAI)"
else
if_TAI_time_format = .false.
xtitle = "Seconds (TAI) labelled with corresponding UTC"
endif
endif
do i=0,npts-1
x(i+1) = xmin + i*(xmax-xmin)/(real(npts-1,kind=pl_test_flt))
tai = x(i+1)
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
call plbtime(tai_year, tai_month, tai_day, tai_hour, &
tai_min, tai_sec, tai)
! Calculate residual using tai as the epoch to nearly maximize time-representation precision.
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
tai_year, tai_month, tai_day, tai_hour, tai_min, tai_sec)
! Calculate continuous tai with new epoch.
call plctime( tai_year, tai_month, tai_day, tai_hour, tai_min, tai_sec, tai)
! Calculate broken-down utc (with leap seconds inserted) from continuous tai with new epoch.
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 2, .true., &
tai_year, tai_month, tai_day, tai_hour, tai_min, tai_sec)
call plbtime(utc_year, utc_month, utc_day, utc_hour, utc_min, utc_sec, tai)
! Calculate continuous utc from broken-down utc using same epoch as for the continuous tai.
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
tai_year, tai_month, tai_day, tai_hour, tai_min, tai_sec)
call plctime(utc_year, utc_month, utc_day, utc_hour, utc_min, utc_sec, utc)
! Convert residuals to seconds.
y(i+1)=(tai-utc)*scale*86400._pl_test_flt
enddo
call pladv(0)
call plvsta()
call plwind(xmin, xmax, ymin, ymax)
call plcol0(1)
if (if_TAI_time_format) then
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 0, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
else
call plconfigtime(scale, 0._pl_test_flt, 0._pl_test_flt, 2, .true., &
epoch_year, epoch_month, epoch_day, epoch_hour, epoch_min, epoch_sec )
endif
call pltimefmt(time_format)
call plbox("bcnstd", xlabel_step, 0, "bcnstv", 0._pl_test_flt, 0)
call plcol0(3)
title = "@frPLplot Example 29 - TAI-UTC "// &
trim(title_suffix)
call pllab(xtitle, "TAI-UTC (sec)", title)
call plcol0(4)
call plline(x(1:npts), y(1:npts))
enddo
end subroutine plot4
end program x29f
|
