# nwARGOS tutorial

Performing a simulation with nwARGOS requires a minimum of the following four files. Following the conventions of the file structure, these are

- project.top, describing the topology of the molecular system,
- project_id.rst, constaining the (re-)start information,
- project_id.inp, providing input details of the simulation to nwARGOS, and
- project_id, providing task and memory information to NWChem.

Setting up a calculation is done in the following order

1. Create segment file project.sgm, using program nwSGM, if needed
2. Create the topology file project.top, using program nwTOP
3. Generate the restart file project_id.rst, using program nwRST
4. Provide in the input file project_id.inp a stream of keywords defining the simulation details
5. Provide in the NWChem input file project_id the task and memory information

The actual simulation is carried out with

`nwchem project_id`

NWChem will read the file project_id, allocate the specified memory and give control to the nwARGOS module. nwARGOS will strip the `project_id` from the command line, and generate all needed filenames, such as project.top, project_id.rst, and project_id.inp from it.