[Gate-users] Re: Gate-users Digest, Vol 14, Issue 18

[Ben McDonald]

Hi Daniel,

I have a slightly convoluted way to make sure my runs are statistically 
independent. First, I use the jobsplitter tool (available in Gate 
v.3.1.0) to make a bunch of seedN.rndm files. Then I use a script that 
makes a copy of my macro, changes the following line, and submits the 
job to the cluster:

/random/resetEngineFrom /home/mcdonabs/.Gate/mpModcamtomo/seed1.rndm

I have root output disabled and this still works.

Since you are using interfile output, have you noticed that the spatial 
blurring does not take effect? How have you rectified the lack of 
spatial blurring?

Cheers,

Ben

gate-users-request at lists.healthgrid.org wrote:
>    1. /gate/output/root/setSaveRndmFlag (Daniel Woodsworth)
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 16 Jul 2007 16:30:53 -0700 (PDT)
> From: "Daniel Woodsworth" <danieljw at phas.ubc.ca>
> Subject: [Gate-users] /gate/output/root/setSaveRndmFlag
> To: gate-users at lists.healthgrid.org
> Message-ID: <38286.137.82.91.46.1184628653.squirrel at www.phas.ubc.ca>
> Content-Type: text/plain;charset=iso-8859-1
>
> Hi,
>
> I am trying to set up a system to run statistically independent
> runs/simulations of a single physical setup (phantom, activity, geometry,
> scanner, electronics etc.) The way I am doing this, is I have a little
> script that takes an old endOfRun.rndm file and edits one of the numbers,
> which (I believe), when the simulation is run from a directory containing
> an endOfRun.rndm file causes Gate to produce a new (independent) stream of
> random numbers. So the script makes multiple, different, endOfRun.rndm
> files and launches a simulation from distinct directories. This all seems
> to work fine and yield independent simulations.
>
> However, if I try and disable the ROOT output (/gate/output/root/disable),
> then I no longer get independent runs. I am guessing this is since the
> setSaveRndmFlag is part of the /root tree structure. Ie the command
> /gate/output/root/disable kills any commands which start with
> /gate/output/root, including setSaveRndmFlag.
>
> At any rate, somehow disabling the ROOT output disrupts the GATE procedure
> of using the endOfRun.rndm file as a starting point for the random number
> generator.
>
> I would like to be able to run simulations with just interfile output, as
> sometimes I only need projection data, and the root output slows down the
> simulation and tends to be very large data files.
>
> Has anyone come across this? Does anyone know how to force GATE to use
> endOfRun.rndm as the starting point for the random number stream, with the
> ROOT output disabled?
>
> Thanks for any help.
>
> Daniel
>
>