**in=***file*- Input data are read from
*file*, which must be in NEMO snapshot format. If*file*=-, input is expected from stdin. Default:**required**. **prop=***expr**expr*must be a*bodiesfunc(5falcON)*expression. It will be used to generate a*bodiesfunc(3falcON)*function. Default:**required**.**pars=***parameter list*- If the
*bodiesfunc(5falcON)*expression given with**prop=**requires parameters (up to 10), these must be provided (as comma-separated list) with**pars=**. No Default. **times=***time range(s)*- Range(s) of simulation times, for which
snapshots shall be processed. Default:
**all**. **zeromissing=t|f**- If true, body
data missing from the snapshot but required for the
*bodiesfunc(3falcON)*function are reset to zero, Otherwise an error is issued and no output is made. Default:**f**.

To evaluate the mass-weighted mean specific
angular momentum of all bodies which rotate prograde around the z-axis,
type

** snapprop in=data prop="Mmean{l@lz>0}"**.

To evaluate the mass within a radius
of 0.1 from the origin, type

** snapprop in=data prop="Sum{m@r<$0}" pars=0.1**.

To obtain the rms radial velocity
of all bound bodies, type

` ` ` ` snapprop in=data prop="sqrt(Mean{vr*vr@E<0})"

(note that for this example the data must contain the body potentials).

To count the number of bodies within four times minimum softening length,
type

** snapprop in=data prop="Num{r<#0*Min{eps}}" pars=4**.

21-jul-2004 CreatedWD 20-aug-2004 improved bodiesfuncWD 07-nov-2004 parameters added, changed cond#expr to expr@condWD 12-jul-2006 UpdatedWD