Added forcezero linesearch method

git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@7676 f3b2605a-c512-4ea7-a41b-209d697bcdaa
This commit is contained in:
athomps
2012-02-02 23:19:50 +00:00
parent 9d88ab7ee1
commit ff1b76a2d2
2 changed files with 18 additions and 12 deletions

View File

@ -20,8 +20,8 @@
<PRE>keyword = <I>dmax</I> or <I>line</I>
<I>dmax</I> value = max
max = maximum distance for line search to move (distance units)
<I>line</I> value = <I>backtrack</I> or <I>quadratic</I>
backtrack,quadratic = style of linesearch to use
<I>line</I> value = <I>backtrack</I> or <I>quadratic</I>or <I>forcezero</I>
backtrack,quadratic,forcezero = style of linesearch to use
</PRE>
</UL>
@ -58,10 +58,13 @@ difference of two large values (energy before and energy after) and
that difference may be smaller than machine epsilon even if atoms
could move in the gradient direction to reduce forces further.
</P>
<P>By contast, the <I>quadratic</I> line search algorithm is often able to
reduce forces closer to 0.0. It may also be more efficient than the
backtracking algorithm by requiring fewer energy/force evaluations.
However, it may not be as robust for some problems.
<P>By contrast, the <I>quadratic</I> line search algorithm tries to
reduce the forces to zero, while guaranteeing that the energy
changes is not positive (uphill). For some systems, it may also
be more efficient than the backtracking algorithm by
requiring fewer energy/force evaluations. The <I>forcezero</I>
line search algorithm is similar to <I>quadratic</I>.
It may be more efficient than <I>quadratic</I> on some systems.
</P>
<P><B>Restrictions:</B> none
</P>

View File

@ -16,8 +16,8 @@ one or more keyword/value pairs may be listed :ulb,l
keyword = {dmax} or {line}
{dmax} value = max
max = maximum distance for line search to move (distance units)
{line} value = {backtrack} or {quadratic}
backtrack,quadratic = style of linesearch to use :pre
{line} value = {backtrack} or {quadratic}or {forcezero}
backtrack,quadratic,forcezero = style of linesearch to use :pre
:ule
[Examples:]
@ -53,10 +53,13 @@ difference of two large values (energy before and energy after) and
that difference may be smaller than machine epsilon even if atoms
could move in the gradient direction to reduce forces further.
By contast, the {quadratic} line search algorithm is often able to
reduce forces closer to 0.0. It may also be more efficient than the
backtracking algorithm by requiring fewer energy/force evaluations.
However, it may not be as robust for some problems.
By contrast, the {quadratic} line search algorithm tries to
reduce the forces to zero, while guaranteeing that the energy
changes is not positive (uphill). For some systems, it may also
be more efficient than the backtracking algorithm by
requiring fewer energy/force evaluations. The {forcezero}
line search algorithm is similar to {quadratic}.
It may be more efficient than {quadratic} on some systems.
[Restrictions:] none