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* R\_1, R\_2,... = list of cutoff radii, one for each type (distance units)

* w\_1, w\_2,... = list of neighbor weights, one for each type

* zero or more keyword/value pairs may be appended

* keyword = *rmin0* or *switchflag* or *bzeroflag* or *quadraticflag*

* keyword = *rmin0* or *switchflag* or *bzeroflag* or *quadraticflag* or *chunksize*

  .. parsed-literal::

       *quadraticflag* value = *0* or *1*

          *0* = do not generate quadratic terms

          *1* = generate quadratic terms

       *chunksize* value = number of atoms in each loop pass (KOKKOS package only)

Examples

detailed explanation of the number of quadratic terms and the

ordered in which they are listed.

The keyword *chunksize* is only applicable when using the

KOKKOS package and is ignored otherwise. This keyword controls

the number of atoms in each pass used to compute the forces

and is use to avoid running out of memory. For example if there

are 4000 atoms in the simulation and the *chunksize* is set to

2000, the force calculation will be broken up into two passes.

.. note::

   If you have a bonded system, then the settings of

with #) anywhere. Each non-blank non-comment line must contain one

keyword/value pair. The required keywords are *rcutfac* and

*twojmax*\ . Optional keywords are *rfac0*\ , *rmin0*\ ,

*switchflag*\ , and *bzeroflag*\ .

*switchflag*\ , *bzeroflag*\, and *chunksize*\.

The default values for these keywords are

* *switchflag* = 0

* *bzeroflag* = 1

* *quadraticflag* = 1

* *chunksize* = 2000

Detailed definitions for all the keywords are given on the :doc:`compute sna/atom <compute_sna_atom>` doc page.

If *quadraticflag* is set to 1, then the SNAP energy expression includes the quadratic term,