AMBER Archive (2002)

Subject: Re: Latest parm + getting parm98 as default in LEaP

From: David Case (case_at_scripps.edu)
Date: Tue Jan 22 2002 - 10:14:55 CST


On Tue, Jan 22, 2002, Lepsa wrote:

> I just want to add an uncertainty about the parameter sets: what happens
> when I load parm94 and parm99 simultaneously under different names? Will
> LEAP use the newer (more complete) version automatically? It does seem to
> work this way but I'm not sure...

LEaP looks for parameters in reverse order of how the parmfiles were loaded:
that is, it searches the last parameter set loaded first. So, if you load
parm94 first, then parm99, parameters in parm99 would be found first and
used.

However, doing this is dangerous: if there are any missing parameters in
the parmset that is examined first, they will be searched for in other
parameter sets, and that might not be what you want.

Also, note that LEaP has no notion that parm99 is "newer" than parm94: it
just goes by the order in which the "loadAmberParams" commands were carried
out.

...good luck...dac

>
> > > Can anyone let me know how to make parm98 (or anyother alternate
> > > parm set) as the default one?
> > ... "parm94 = loadamberparams parm99.dat"
> > in the leaprc file does the trick
> > (I know the naming is stupid ;-)

Well, yes, this is pretty confusing. Why not just say:

parm99 = loadamberparams parm99.dat

-- 

================================================================== David A. Case | e-mail: case_at_scripps.edu Dept. of Molecular Biology, TPC15 | fax: +1-858-784-8896 The Scripps Research Institute | phone: +1-858-784-9768 10550 N. Torrey Pines Rd. | home page: La Jolla CA 92037 USA | http://www.scripps.edu/case ==================================================================