Populates a periodic_spline instance spl representing the
periodic data y(x) of length n and periodic on period. Note
that the spline library expects period > x(n) - x(1), which
means the input data shouldn't include the duplicate periodic
point. As a convenience the user can pass data with the
duplicate point and set drop_last_point = .true. to
automatically exclude the duplicate point.
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real, | intent(in), | dimension (:) | :: | x | ||
| real, | intent(in), | dimension (:) | :: | y | ||
| real, | intent(in) | :: | period | |||
| logical, | intent(in), | optional | :: | drop_last_point | ||
| real, | intent(in), | optional | :: | tension |
type(periodic_spline) function new_periodic_spline (x, y, period, &
drop_last_point, tension) result(spl)
use optionals, only: get_option_with_default
implicit none
real, dimension (:), intent (in) :: x, y
real, intent (in) :: period
logical, intent(in), optional :: drop_last_point
real, intent(in), optional :: tension
logical :: drop_point
real, dimension (:), allocatable :: temp
integer :: ierr
spl%valid = .false.
drop_point = get_option_with_default(drop_last_point, .false.)
spl%tension = get_option_with_default(tension, 1.0)
spl%n = size(x)
if (drop_point) spl%n = spl%n - 1
allocate(spl%x, source = x(:spl%n)) ; allocate(spl%y, source = y(:spl%n))
allocate (spl%y2(spl%n), temp(2*spl%n))
spl%period = period
call fitp_curvp1 (spl%n,spl%x,spl%y,spl%period,spl%y2,temp,spl%tension,ierr)
spl%valid = ierr == 0
end function new_periodic_spline