writegadget: Write simulation snapshot in Gadget-2 binary format

In obreschkow/simstar: Reading, processing and visualising astrophysical N-body simulation data

Description

Write astrophysical N-body+SPH snapshot in Gadget-2 binary format, for use as initial conditions with Gadget Version 1/2/3/4 (SnapFormat=1).

Usage

writegadget(part, head, file)

Arguments

part	is a list of initial conditions. It contains the items: x = N-by-3 matrix specifying the initial position in Cartesian coordinates of the N particles v = optional N-by-3 matrix specifying the initial velocities. If not given, velocities are set to zero. id = optional N-by-3 matrix specifying unique particle IDs. If not given, the particles will be numbered sequentially from 1 to N. m = optional vector giving the masses of the particles, whose mass is not already specified in head$Massarr. This is only used for variable particles masses. Fixed masses are best specified with the header argument Massarr. u = optional vector giving the internal energies of the SPH particles, i.e. the particles of type 0 (in C-indexing).
head	is a list of header arguments. For full details, please refer to the Gadget-2 manual (https://wwwmpa.mpa-garching.mpg.de/gadget/users-guide.pdf, page 33). The most important items are: Npart = 6-vector giving the number of particles of each type. The first element corresponds to gas particles; the other five are treated as collision-less. NMassarr = optional 6-vector listing a fixed mass for each particle type. If set to 0 for a type which is present, individual particle masses must be provided in the vector part$m.
file	filename.

Value

Returns a list containing the particle data. The format of the list depends on the input format.

Author(s)

Danail Obreschkow

See Also

readgadget

obreschkow/simstar documentation built on Jan. 29, 2022, 2:16 p.m.