Change Output Frequency?

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osean
Posts: 47
Joined: Sat Jan 23, 2021 3:46 pm
Location: MIT-WHOI

Change Output Frequency?

#1 Unread post by osean »

Hello All,

I am trying to produce a year-long simulation, with high output frequency over a particular period of time.

At the moment, I only manage to increase output frequency for the entire simulation duration through NHIS in roms_.in file:
Output history, average, diagnostic files parameters.
LDEFOUT == T ! File creation/append switch
NHIS == 72 ! Number of timesteps between writing history records
NDEFHIS == 0 ! Number of timesteps between creation of new history file
NQCK == 0 ! Number of timesteps between writing quicksave records
NDEFQCK == 0 ! Number of timesteps between creation of new quicksave file
NTSAVG == 1 ! Starting averages timestep
NAVG == 72 ! Number of timesteps between writing averages records
NDEFAVG == 0 ! Number of timesteps between creation of new averages file
NTSDIA == 1 ! Starting diagnostics timestep
NDIA == 72 ! Number of timesteps between writing diagnostics records
NDEFDIA == 0 ! Number of timesteps between creation of new diagnostics file
However, that means my output file will be extremely large. I only look for high output frequency over a specific month period in the middle of the simulation, and the rest I only need sporadic outputs. Is there any way we can set varying number of timesteps between creation of writing history records? I see that I can create new history files, but not varying output timesteps among files...

Greatly appreciate any hints...!

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kate
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Joined: Wed Jul 02, 2003 5:29 pm
Location: CFOS/UAF, USA

Re: Change Output Frequency?

#2 Unread post by kate »

You can run for a bit with one output frequency, then restart with a different output frequency. Anything more fancy is going to take hacking the code.

osean
Posts: 47
Joined: Sat Jan 23, 2021 3:46 pm
Location: MIT-WHOI

Re: Change Output Frequency?

#3 Unread post by osean »

kate wrote: Sat Sep 04, 2021 1:18 pm You can run for a bit with one output frequency, then restart with a different output frequency. Anything more fancy is going to take hacking the code.
I noticed that there's a restart file option. How does one go about restarting with a different output frequency from a restart .nc file?

Kosa
Posts: 35
Joined: Mon Jan 12, 2015 4:12 pm
Location: URI GSO

Re: Change Output Frequency?

#4 Unread post by Kosa »

osean wrote: Wed Sep 08, 2021 12:51 pm
I noticed that there's a restart file option. How does one go about restarting with a different output frequency from a restart .nc file?
You will create a 2nd ocean.in file with a new NHIS and set ININAME to point to your restart file. Note that you will also want to set NRREC to -1.

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