A good start is the manual page programs(8NEMO) , which lists programs thematically, and index(1NEMO) , which lists them alphabetically (CAVEAT: these pages are often out of date).
NEMO is very much integrated into the Unix(tm) operating system, so users are expected to use standard Unix or Local commands as glue between the various tasks (cat, ls, rm, cp, awk, mongo, sm, etc.). Understanding of shell scripting (sh,csh,python,perl,...) can be very useful. Several example shell scripts exist in the source code to demonstrate how experiments can be orchestrated.
The easiest way is to add the appropriate line to your .cshrc or .bashrc
file:
source $NEMO/nemo-start.csh
or
source $NEMO/nemo-start.sh
If you need more control over your environment, there are other methods described elsewhere (The NEMO Users/Programmers Guide, Appendix A), or consult one of your local or remote friendly NEMO users.
NEMO programs all work by using a series of keyword=value pairs on the commandline. If the order of the supplied keywords is the same as the program expects them, the keyword= part can be omitted, simply to save keystrokes. There is a consistent ordering of keywords in most programs that allows experienced users to use such (and other) shortcuts. (e.g. in= the first one, out= the second one etc.). Keywords can be used in minimum match, but this is not recommended for shell scripts.
NEMO programs make a distinction between program keywords (keywords unique to a program) and system keywords (a fixed set of keywords that each NEMO program understands). The system keywords that you are likely to use are help= and yapp=, and to a lesser degree debug= and error=. The help= gives various types of inline aid from a program. There is also online help on a program, for which unix man(1) command (or any of it's derived friends) is normally used. The yapp= sets the graphics device used by programs who use a graphics device. You system manager may have given you a default.
Each system keyword can be defaulted by setting it's equivalent environment variable (in upper case though). Program keywords can be abbreviated to uniqueness.
Examples: Consider the program
mkplummer, a program which creates an N-body realization of a Plummer sphere:
To get online help, one types:
man mkplummerand to get various types of inline help:
mkplummer help=
mkplummer help=h
mkplummer help='?'
Note the literal quotes around the question-mark needed if you use a regular
Unix shell as interface. The first help= reminds you of the order of the
program keywords and their default values. The second form, help=h prints
out a small one-line reminder what each keyword means. The last form help='?'
lists various options the user interface understands, this one is not program
dependant.
If you chain NEMO programs, pipes can be a very efficient way
to prevent large amounts of disk access. Most keywords that operate on
files (notably in=, out=, as long as stropen(3NEMO)
is used) can use standard
piped I/O by using the dash (-) to name the keyword, e.g.
mkplummer - 100 | tsf -would create a snapshot of 100 bodies on the fly, and display it to the user using tsf. The alternative would have been
mkplummer out=tmp nbody=100
tsf in=tmp
rm tmp
Various man(1NEMO) pages explain programs(1) , subroutine libraries(3) file formats(5) and system management(8) .
The World Wide Web homepage http://www.astro.umd.edu/nemo.