Re: [AMBER-Developers] XMIN minimisation and coordinates

From: Ben Roberts <>
Date: Tue, 1 Mar 2011 23:58:46 -0500

Hi Istvan,

On 1/03/2011, at 11:47 PM, wrote:

> The return_flag values are defined below. OLDNBL and NEWNBL are used
> in NAB referring to whether XMIN needs a new energy/gradient with the
> current nonbonded list (OLDNBL) or requires a forced nonbonded list
> update (NEWNBL). When "MIN:" is printed NEWNBL is used. Values 1, 2,
> and 3 leave the decision of whether or not to update the list, to NAB.
> If I remember correctly, this distinction is not made in Sander and,
> therefore, 1, 4, and 7 are equivalent and, similarly, 2=5=8, and
> 3=6=9, respectively.

I believe that's not true. In sander, there's a CASE statement that sends the code down one path if the value is DONE; another if the value is CALCENRG, CALCGRAD or CALCBOTH; a third if the value is CALCENRG_NEWNBL, CALCGRAD_NEWNBL or CALCBOTH_NEWNBL; and a fourth if the value is CALCENRG_OLDNBL, CALCGRAD_OLDNBL or CALCBOTH_OLDNBL. (A fifth option, the "default", triggers an ASSERT.)

Have you any thoughts on my other question, specifically: under what conditions are the lines starting "MIN:" printed out in xminC.c (assuming the appropriate verbosity is turned on)? I want to be able to capture the coordinates at those points - where a minimisation iteration is recorded.


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Received on Tue Mar 01 2011 - 21:00:05 PST
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