NEMO is a toolbox for stellar dynamics, particle simulations, stellar orbits,
image processing and tabular data manipulation. Documentation is maintained
in the github pages, https://teuben.github.io/nemo

## History

This is the 4th major release of NEMO,  and although data are compatible
with earlier releases, old source code may need to be tweaked a
bit to compile and link in the newer releases. Some compatibility with ZENO
is also advertised. A brief history of NEMO:

   * NEMO V1:	IAS release (Barnes, Hut & Teuben, 1987)
   * NEMO V2:	UMD release (Teuben, 1994)
   * NEMO V3:	UMD release (Teuben, 2001) in CVS, with autoconf support and
		hooks into manybody.org modules starlab and partiview
   * NEMO V4:   UMD/ESO release (2017) now maintained in github

A related package, ZENO, was spun off NEMO V1, and is maintained by Josh Barnes. 
Other packages that geneologically came after NEMO are StarLab, ACS and AMUSE
(see also https://ascl.net for code references):

	 NEMO:      ascl:1010.051
	 ZENO:      ascl:1102.027 (normally installed in $NEMO/usr/zeno)
	 STARLAB:   ascl:1010.076
	 ACS:       https://artcompsci.org
	 AMUSE:     ascl:1107.007
	 
## Optional Packages

Packages we optionally use (sometimes also installed in $NEMO/opt with source code in $NEMO/local):

	 PGPLOT:    ascl:1103.002
	 CFITSIO:   ascl:1010.001
	 WCSLIB:    ascl:1108.003
	 glnemo2:   ascl:1110.008
	 gyrfalcON: ascl:1402.031 (included with NEMO)
	 HDF4
	 HDF5       https://www.hdfgroup.org
	 netcdf4
	 gsl
	 plplot
	 unsio
	 uns_project
	 wcstools

Tools you will need to have pre-installed: the C/C++/Fortran
compilers, (t)csh, and git.  For graphics it's probably
useful to have pgplot, but the default ps driver works
fine just to get started quickly.

The files in $NEMO/src/scripts/linux describe the actual package
names for different linux distros that should lead to success.


## Installation

There are a few different ways to install NEMO, here is a basic
example that works most of the time on most Linux distros (assuming
you have the preconditions):

         git clone https://github.com/teuben/nemo
         cd nemo
         ./configure --with-yapp=pgplot
         make build check bench5
         source nemo_start.sh

If you plan to modify code and submit pull request, the github CLI is now recommended,
though you can of course also clone the upstream manually (see also [CONTRIBUTING.md](CONTRIBUTING.md)):

         gh repo fork https://github.com/teuben/nemo

On the most recent apple controlled hardware, with SIP enabled, you're in for a rude
awakening. I use brew, and assuming you have gcc-10 (and related) and pgplot installed, this should
work (there may be other ways to install tools on a mac, but don't get me started):

         git clone https://github.com/teuben/nemo
         cd nemo
         CC=gcc-10 CXX=g++-10 F77=gfortran-10 ./configure --disable-shared --with-yapp=pgplot
         make build check bench5
         source nemo_start.sh

After installaton, rebuilding NEMO to ensure you have all updates can be done as follows:

         cd $NEMO
         git pull
         make rebuild

### python

There is now a small python component to NEMO, in the **nemopy** module.

         cd $NEMO
         pip install -e .

but this will depend on the details of how your python environment exists (virtual, conda etc.).
We leave this to the user.
		 
## Examples		 

If you want to quickly see something work, here are the commands to
make a classic 1911 Plummer sphere of just 10 particles, print the positions, plot
the positions and view the contents of its binary file:

         mkplummer p10.dat 10
         snapprint p10.dat
         snapplot p10.dat
         tsf p10.dat

and here is an example of creating the 4 major data objects on the fly in NEMO
(table, snapshot, image, orbit), showing off the command line interface and
use of unix pipes with a dash denoting the piped file:

         tabgen -  | tabplot -
         mkplummer - 100 | snapplot - 
         ccdgen out=- object=gauss spar=1,20 size=128 | ccdplot - 
         mkorbit - 0 1 0  0.4 0 0 potname=plummer | orbint - - nsteps=1000 dt=0.05 | orbplot - 

There are more examples of scripts and figures in
https://teuben.github.io/nemo/examples/ 
and an example ipython notebook is shown here
https://github.com/teuben/nemo/blob/master/nemo_start_example.ipynb
for something completely different.

## Documentation and Help

There are several additional entry points if you are starting out with NEMO:

* readthedocs: https://astronemo.readthedocs.io/en/latest/
* github pages: https://teuben.github.io/nemo
* software carpentry: https://teuben.github.io/nemo-lesson 
* contributing to NEMO: CONTRIBUTING.md

## Citation

Please use the following citation if you use NEMO in your work


     @INPROCEEDINGS{1995ASPC...77..398T,
            author = {{Teuben}, P.},
             title = "{The Stellar Dynamics Toolbox NEMO}",
         booktitle = {Astronomical Data Analysis Software and Systems IV},
              year = 1995,
            editor = {{Shaw}, R.~A. and {Payne}, H.~E. and {Hayes}, J.~J.~E.},
            series = {Astronomical Society of the Pacific Conference Series},
            volume = {77},
             month = jan,
             pages = {398},
            adsurl = {https://ui.adsabs.harvard.edu/abs/1995ASPC...77..398T},
           adsnote = {Provided by the SAO/NASA Astrophysics Data System}
     }


![A Real Bar](docs/figures/realbar1.png)