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subroutine da_truncate_spectra(max_wave, nw, power_trunc, power, max_wave_trunc) 5,3
!-----------------------------------------------------------------------
! Purpose: TBD
!-----------------------------------------------------------------------
implicit none
integer, intent(in) :: max_wave ! Smallest wave for domain.
integer, intent(in) :: nw ! Dimension of input power spectrum.
real, intent(in) :: power_trunc ! Power truncation (fraction).
real*8, intent(in) :: power(0:nw) ! Power spectrum.
integer, intent(out) :: max_wave_trunc ! Smallest wave after truncation.
integer :: l ! Loop counter.
real :: truncated_power ! Truncated power.
real :: cumul_power ! Cumulative power.
if (trace_use) call da_trace_entry
("da_truncate_spectra")
truncated_power = power_trunc * sum(power(0:nw))
cumul_power = 0.0
max_wave_trunc = max_wave
do l = 0, nw - 1
cumul_power = cumul_power + power(l)
if (cumul_power > truncated_power) then
max_wave_trunc = l - 1
exit
end if
end do
if (max_wave_trunc > max_wave) then
write(unit=message(1),fmt='(a)') &
'da_truncate_spectra: Power requested needs higher resolution.'
write(unit=message(2),fmt='(a,i8)') &
'Maximum grid wavenumber = ', max_wave
write(unit=message(3),fmt='(a,i8)') &
'Truncating to wavenumber = ', max_wave_trunc
call da_warning(__FILE__,__LINE__,message(1:3))
max_wave_trunc = max_wave
end if
if (trace_use) call da_trace_exit("da_truncate_spectra")
end subroutine da_truncate_spectra