Table of Contents

For that matter *snapscale* is not an
intelligent program. One could set it up with default not supplied (empty
keywords), and let the program figure out how to rescale all available
items in the snapshot if e.g. only masses are scaled, and virial units are
to be effective, the radii and/or velocities will also be appropriately
scaled. These features are implemented in *snapvirial*.

**in=***in_file*- input file, in
*snapshot*(5NEMO) format. Default: none. **out=***out_file*- output file, also
*snapshot*format. Default: none. **mscale=***m_scale_factor*- Scale factor for particle masses. Default:
**1.0**. **rscale=***pos_scale_factor(s)*- Scale factor for position space. If three numbers are given, the three positions
are scaled independantly. One number means all NDIM (three or two) coordinates
are transformed the same. Default:
**1.0**. **vscale=***vel_scale_factor(s)*- Scale factor
for velocity space. If three numbers are given, the three velocities are
scaled independantly. One number means all NDIM (three or two) coordinates
are transformed the same. Default:
**1.0**. **pscale=***phi_scale_factor*- Scale factor
for particle potentials. Default:
**1.0**. **ascale=***acc_scale_factor(s)*- Scale factor
for accelerations. If three numbers are given, the three accelerations
are scaled independantly. One number means all NDIM (three or two) coordinates
are transformed the same. Default:
**1.0**. **xscale=***aux_scale_factor*- Scale factor
for the auxilliary information item, if present. Default:
**1.0**. **kscale=***key_scale_factor*- Scale factor for the key item. Note that this item must be an integer. Default:
**1**. **times=***time-ranges*- Only snapshots with time values within
*times-ranges*, which is of the form**ts[:te],...**, will be copied. [default:**all**].

e=1.1 snapscale in=mod.axi out=mod.ell "rscale=sqrt($e),1/sqrt($e),1" \ "vscale=$e,1/$e,1"

Scaling an already virialized Plummer sphere (see *mkplummer(1NEMO)*
), and
the Faber-Jackson relation, here is one way to scale such models with a
massfraction **a**:

a=0.1 snapscale plum1.dat plum2.dat mscale="$a" rscale="$a**0.5" vscale="$a**0.25"

~/src/pjt/nbodysnapscale.c snapscale.1

7-May-87V1.0: createdPJT 16-Nov-87V1.1: mass addedPJT 9-Mar-88V1.2: data history added, proper debug outputPJT 16-Mar-88V1.0 at IAS by JoshJEB 1-Jun-88V2.0: merged PJT extensions into JEB’s codePJT 24-aug-88V2.1: added pscale keywordPJT 15-aug-89V2.4: added pscale,ascale,xscale,kscalePJT 19-oct-99doc improvedPJT 13-jun-22add examplePJT