Table of Contents

A number
of random angles can optionally be choosen for each point to be rotated
before it is projected. A random orientation is achieved by 2 rotations:
one in polar angle phi (0..2PI) followed by a random value of cos(theta)
where theta is 0..PI away from the Z axis. The histogram counts are then normalized
by **nrand**. This then means that the histograms are completely normalized,
it’s integral being the total mass.

A little on the background of this program: (dumbell)

*snaphist* does not use *yapp(3NEMO)*
yet, it produces a table, meant
for *mongo(1LOCAL)*
or *tabhist(1NEMO)*
.

**in=***in_file*- input file, in
*snapshot*(5NEMO) format. [Default: none]. **rad=***real-array*- boundaries of the projected radii which should be used
to construct the histogram. [
**0:2:0.05**]. **vel=***real-array*- boundaries of the radial
velocities which should be used to construct the histogram. [
**-2:2:0.1**]. **nrand=***int*- Number of random angles used for each point before it is projected. Only
positive values are used. [default:
**0**]. **seed=***int*- A random seed for the random
number generator. A value of zero means time of day is taken as random seed.
[
**0**]. **tab=r|v|s|rv**- Table needed of radii (
**r**) or velocities (**v**). A scatter table of velocity vs. radius can be obtained with**s**. If the option**rv**is taken, and the number of bins in radius and velocity is the same, both radius and velocity columns will be output. Radius in columns 1 and 2, velocity in 3 and 4. [default: r].

~/src/pjt/nbodysnaphist.c snaphist.1

19-jun-89V1.0: createdPJT 27-jul-89V1.1: more efficient random anglesPJT