Run Cluster on different origin lat-longtitude

Topics about the trajectory clustering program for HYSPLIT.
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yuejun0026
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Joined: May 28th, 2014, 7:15 am
Registered HYSPLIT User: Yes

Run Cluster on different origin lat-longtitude

Post by yuejun0026 » May 28th, 2014, 7:40 am

Hello all,
Pardon my poor English,
I have chosen 36 origin points in 3 levels of 500m/1500m/3000m in the area of 27.5-32.5N/100-107.5E. After i push the cluster button,
It gives me an error like this:
ERROR - origin lat-lon for all trajectories must be identical. Differs in tdump...
but I am sure they have all the same long lat origin.

after i deleted some days tdump and it worked,but the origin lat-lon in left tdumps are still different. Could you tell me why?

Besides i want the specific humidity after cluster, but the pressure ,specific humidity and so on in the file of cmean are all 0.0. Is it impossible to get specific humidity?

By Yue
Thank you very much

barbara.stunder
Posts: 273
Joined: November 9th, 2012, 4:23 pm
Registered HYSPLIT User: Yes

Re: Run Cluster on different origin lat-longtitude

Post by barbara.stunder » May 28th, 2014, 2:52 pm

In the set of trajectories to be clustered, the origin (trajectory start latitude-longitude) need to be the same.

Originally the cluster program was limited to a single trajectory in a file (one start level only) and no diagnostic variables such as specific humidity. Do you have the three levels in one trajectory file? If so, you need to re-run the trajectories one level at a time and use them for the cluster program. Regarding the diagnostic variables, I need to look back at the code, but I think it can do the clustering of the trajectories, however, you would need to do your own averaging of the specific humidity, etc, using the CLUSLIST file which shows you which trajectories are in each cluster.

yuejun0026
Posts: 4
Joined: May 28th, 2014, 7:15 am
Registered HYSPLIT User: Yes

Re: Run Cluster on different origin lat-longtitude

Post by yuejun0026 » August 14th, 2014, 8:44 am

Thanks for your answer!
But I must cluster in a area that mean the origin start point must be differ. Is there some measures to do like it? Somebody tell me if i can shift the original point into one start point which have the same latitude and longitude? Is it useful? Or can you tell me how to shift the original point ?
Thank you very much!

barbara.stunder
Posts: 273
Joined: November 9th, 2012, 4:23 pm
Registered HYSPLIT User: Yes

Re: Run Cluster on different origin lat-longtitude

Post by barbara.stunder » August 14th, 2014, 11:25 am

The clustering assumes that all trajectories start at the same latitude-longitude, and so there is a check for that in the code.

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