pair_style table multiple values for N

I was wondering if it is possible to use the pair_style table (spline or linear) with different values of N? The potentials I am using have varied range, and shouldn’t necessarily contain the same number of sample points.

My temporary fix is to ‘over’ sample the potential with the small range so that the larger potential is sufficiently sampled with some value N. For future situations, though, it may be nice if these tables could be different length.s

  • Bryan

bryan,

I was wondering if it is possible to use the pair_style table (spline or
linear) with different values of N? The potentials I am using have varied
range, and shouldn't necessarily contain the same number of sample points.
My temporary fix is to 'over' sample the potential with the small range so
that the larger potential is sufficiently sampled with some value N. For
future situations, though, it may be nice if these tables could be different
length.s

what kind of a benefit would you expect from this?
i don't quite see, how this would make a significant
difference anywhere.

cheers,
    axel.

Axel,

I suppose there is no advantage per se, except it could save a slight amount of effort when generating the potential tables.

Thank you anyways!

  • Bryan

bryan,

Axel,
I suppose there is no advantage per se, except it could save a slight amount
of effort when generating the potential tables.

but this is already availble.
please have a closer look at the documentation.

the N value that you specify with the pair style
is the number of table points used to represent
the potenntial. the tables themselves can have different
number of data points and representations.
the pair style will read the table and then re-interpolate
the data via splines from the table data to represent it
in the way described in the pair style command.
that being said, it is usually better to not have
LAMMPS do the interpolation, or at least carefully
check it for correctness. splines can easily produce
unwanted artifacts.

cheers,
    axel.