git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@8012 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
pscrozi 2012-04-10 17:11:48 +00:00
parent 20ca0b2bce
commit c4fc0d38a6
2 changed files with 10 additions and 0 deletions

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@ -94,6 +94,9 @@ interpolation "features" you may not like.
file, and use the "RSQ" or "BITMAP" parameter, so additional interpolation
is not needed. See discussion below.
<LI>Make sure that your tabulated forces and tabulated energies are consistent
(dE/dr = -F) along the entire range of r values.
<LI>Use as large an inner cutoff as possible. This avoids fitting splines
to very steep parts of the potential.
</UL>
@ -134,6 +137,7 @@ force for individual pair distances. This means that if you want the
interpolation tables of length Ntable to match exactly what is in the
tabulated file (with effectively no preliminary interpolation), you
should set Ntable = Nfile, and use the "RSQ" or "BITMAP" parameter.
The internal table abscissa is RSQ (separation distance squared).
</P>
<P>All other parameters are optional. If "R" or "RSQ" or "BITMAP" does
not appear, then the distances in each line of the table are used
@ -145,6 +149,7 @@ values in regions of large gradients.
and <I>rhi</I>. If specified, the distance associated with each energy and
force value is computed from these 2 values (at high accuracy), rather
than using the (low-accuracy) value listed in each line of the table.
The distance values in the table file are ignored in this case.
For "R", distances uniformly spaced between <I>rlo</I> and <I>rhi</I> are
computed; for "RSQ", squared distances uniformly spaced between
<I>rlo*rlo</I> and <I>rhi*rhi</I> are computed.

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@ -89,6 +89,9 @@ Use {N} in the pair_style command equal to the "N" in the tabulation
file, and use the "RSQ" or "BITMAP" parameter, so additional interpolation
is not needed. See discussion below. :l
Make sure that your tabulated forces and tabulated energies are consistent
(dE/dr = -F) along the entire range of r values. :l
Use as large an inner cutoff as possible. This avoids fitting splines
to very steep parts of the potential. :l,ule
@ -129,6 +132,7 @@ force for individual pair distances. This means that if you want the
interpolation tables of length Ntable to match exactly what is in the
tabulated file (with effectively no preliminary interpolation), you
should set Ntable = Nfile, and use the "RSQ" or "BITMAP" parameter.
The internal table abscissa is RSQ (separation distance squared).
All other parameters are optional. If "R" or "RSQ" or "BITMAP" does
not appear, then the distances in each line of the table are used
@ -140,6 +144,7 @@ If used, the parameters "R" or "RSQ" are followed by 2 values {rlo}
and {rhi}. If specified, the distance associated with each energy and
force value is computed from these 2 values (at high accuracy), rather
than using the (low-accuracy) value listed in each line of the table.
The distance values in the table file are ignored in this case.
For "R", distances uniformly spaced between {rlo} and {rhi} are
computed; for "RSQ", squared distances uniformly spaced between
{rlo*rlo} and {rhi*rhi} are computed.