Last checked or modified: Nov. 3, 1996
- NNES
- A Fortran package for solving nonlinear equations with
simple bound constraints. The documentation
is contained within a 100+ page user's manual
in PostScript format in the same directory as the software
package.
[http://www.netlib.org/opt/index.html]
- NNFit
- The Neural Network-based data Fitting package
allows the development of empirical nonlinear correlations via the
use of an artificial neural network model, i.e. the multilayered
Perceptron. This nonlinear regression software enables the user
to find relationships between a set of input variables and
a set of output variables given a set of relevant experimental
data. The quality of the models obtained depend on the relevance
and quality of the available data.
NNFit distributions are available in precompiled binary format
for IBM AIX, Digital UNIX, HP-UX, Linux Intel, SGI IRIX, and
Sun SunOS platforms. A user's manual is available in
HTML and PostScript formats.
[http://web.gch.ulaval.ca/~nnfit/]
- NNSYSID
- A set of Matlab tools for neural network based
identification of nonlinear dynamic systems. NNSYSID contains a number of
m and MEX files for the training and evaluation of multilayer
perceptron type neural networks. There are functions for training
ordinary feedforward networks as well as for the identification of nonlinear
dynamic systems for time series analysis.
This requires Matlab 4.2 or 5 and the signal processing toolbox.
[http://www.iau.dtu.dk/research/control/nnsysid.html]
- NOCOL
- The Network Operation Center
On-Line/NetConsole software is a network monitoring
package which runs on UNIX platforms and is capable of monitoring
network and system variables such as ICMP or RPC reachability, RMON
variables, nameservers, Ethernet load, port reachability,
host performance, SNMP traps, modem line usage, Appletalk
and Novell routes/services, BGP peers, and more.
It is built to be extensible with the process of adding
new monitors straightforward.
It consists of several individual, standalone monitoring agents which
poll various network and system parameters and put the results into
a common data format used by a common display and
postprocessing interface (which uses the Ncurses
screen management package for portability).
This design allows running only one set of monitoring agents and
any number of display agents.
Each event can also be assigned a severity with levels ranging from
info through critical.
The monitoring agents included in NOCOL are:
- an IP ICMP monitor using IP multiping,
- an OSI reachability monitor using OSI ping,
- an RPC portmapper monitor using rpcping,
- an Ethernet load monitor for both bandwidth and pps,
- a TCP port monitor,
- a UNIX host performance monitor
(for disks, memory, swap, load, etc.),
- a SNMP variables monitor (RMON, Cisco router, terminal server),
- a TCP data throughput monitor,
- a nameserver monitor,
- a SNMP traps monitor,
- a BGP peer status monitor, and
- monitors for Appletalk routes (for Cisco routers) and Novell services.
A Perl interface is also available for developing additional
monitors using Perl.
A source code distribution of NOCOL is available.
It is written in C and Perl and can be compiled and used
on most UNIX flavors.
Documentation is included in the distribution.
[ftp://ftp.navya.com/pub/vikas/]
- NoSQL
- A database package that uses SQL. More later.
[ftp://ftp.linux.it/pub/database/RDB/]
- NOWEB
- A Literate Programming
tool designed to be as simple as possible.
It is simple, extensible, and language-independent. It works
out of the box with any programming language, and supports
TeX,
LaTeX,
and HTML back ends. It also contains a simple
LaTeX-to-HTML converter.
The October 1997 issue of the
Linux Journal contains an
article about NOWEB.
See Ramsey (1994).
[http://www.cs.virginia.edu/~nr/noweb/intro.html]
- NR
- A Tcl/Tk-based
graphical newsreader that supports multiple
fonts and colors, MIME display of articles, true threading,
multiple groups at one time, multiple newsgroup profiles, news
filtering, the Grouplens collaborative filtering architecture,
and more. It is presently (10/95) in the Alpha stage with
a Beta test version available "soon".
[http://www.cs.umn.edu/~herlocke/nr/nr.html]
- nroff
- See Groff.
- NSAPY
- An extension to the Netscape HTTP server that embeds
Python within the server using the
NSAPI protocol. NSAPY allows you to write real NSAPI
applications using Python.
[http://www.ispol.com/home/grisha/nsapy/nsapy.html]
- NSBD
- The Not-So-Bad Distribution is an
open WWW-based authenticating software distribution system.
It adds two things to simple web downloads:
authentication of package maintainers with digital signatures and
a means of checking for updates to the packages and automatically
downloading and installing the updates.
NSBD uses PGP for authentication.
The single packages handles the operations of both maintainers
and uses of packages.
The operation of NSBD by maintainers entails them making the
package available at some site, creating a NSBD Package Description
(NPD) file which describes the package, and running NSBD
interactively with the NPD file to indicate that the package has
been approved. This creates an NSB file containing the URLs for
all files in the package, message digests for each file, and digital
signature created by PGP for the whole file. The NSB file is made
available.
A user selects the URL of a NSB file to invoke NSBD with the
register option, an act which opens a window from which the package
can be registered and installed. NSBD is then run with the poll
option periodically to check for changes to the NSB file.
This process assures the user that only updates from the authorized
maintainer will be automatically installed since only the authorized
maintainer controls the PGP private key.
Binary distributions for the NSBD system are available for
Linux Intel, HP-UX, SGI IRIX, and Sun SunOS and Solaris systems.
A source code distribution is also available which requires
Tcl 7.6 and Tk 4.2 for installation.
It is documented via a man page.
[http://www.bell-labs.com/nsbd]
- nsgmls
- A replacement for sgmls which is
included in the SP package.
- NSPCG
- A package for solving large sparse systems of linear equations by
iterative methods. NSPCG uses various acceleration techniques such
as conjugate gradients, Chebyshev acceleration, and various
generalized conjugate gradient methods for nonsymmetric systems in
conjunction with various preconditioners. The purposes for developing
this package included investigating the suitability of various iterative
methods for vector computers and providing a common modular structure
for research on iterative methods.
The features of NSPCG include:
provision of accelerators for the nonsymmetrizable case such as ORTHOMIN,
generalized conjugate residual (GCR), Lanczos, and LSQR in addition to
those for the symmetrizable case;
several basic preconditioners such as Jacobi, incomplete LU decomposition,
modified incomplete LU decomposition, successive overrelaxation (SOR),
and symmetric successive overrelaxation (SSOR) with some available either
as left-, right-, or two-sided preconditioners;
modularity which allows any preconditioner to be used with any
accelerator and any preconditioner to be used with any of the available
data storage formats;
several matrix storage schemes including primary stoarge (i.e. that
used in ELLPACK), symmetric diagonal storage, nonsymmetric diagonal
storage, symmetric coordinate storage, and nonsymmetric coordinate storage;
capability of usage in a matrix-free mode in which the user supplies
customized routines for performing matrix operations;
data structures chosen for efficiency on vector or pipelined computers;
and more.
The source code for NSPCG is available. It is written in
Fortran 77.
The package is documented in an 80+ page user's manual
in LaTeX format.
Several example codes are included in the distribution.
[ftp://rene.ma.utexas.edu/pub/CNA/ITPACK/]
- NSWC Library
- The Naval Surface Warfare Center's library of general
purpose Fortran routines
contains over 800 programs and
takes up 3.2 Mb compressed.
[ftp://news.rrz.uni-koeln.de/mathematik/]
- Nt
- A shared text editor designed for use on the
MBone.
Nt is highly interactive in that unless a block of text is locked
anyone is a session can edit or delete that text.
Many people can simultaneously edit the same document or even
the same block of text.
[http://mice.ed.ac.uk/mice/archive/nt.html]
[http://nic.merit.edu/net-research/mbone/index/titles.html
]
- nTeX
- A TeX distribution for
Linux that contains the basic TeX distribution along with Metafont
and quite a few fonts and additional macros to perform various
tasks, ring various bells, and blow various whistles. A list of
the contents of the distribution can be found at the
NTeX Web Site
as well as update information. The complete
distribution (as of 1/96) consists of 25 disks (or equivalent files).
A basic installation requires only 9 disks with the remaining 16
containing ever more complicated software to do fancier things.
[http://sunsite.unc.edu/pub/Linux/apps/tex/ntex/]
[ftp://ftp.cc.gatech.edu/pub/linux/apps/tex/ntex/
]
- NTFS
- A driver for the Microshaft Windows NT File System.
The distribution consists of a set of tools including:
ntchange, to change directories on the NTFS;
ntdump, to obtain a list of file attributes;
ntgrep, to search a file for a string;
ntdir, to obtain a listing of files in the NTFS; and
ntcat, to concatenate files in the NTFS.
The release of 2/12/97 is still considered an alpha release, with
the documentation very sparse.
See also the VFAT filesystem.
[http://www.informatik.hu-berlin.de/~loewis/ntfs/]
- NTL
- The Number Theory
Library is a high performance, portable
C++ library providing data structures and algorithms for
manipulating signed, arbitrary length integers as well as
for vectors, matrices, and polynomials over the integers and
over finite fields. The package also uses state-of-the-art algorithms,
e.g. the code for polynomial arithmetic is one of the fastest
available. NTL is not meant to be a complete computer algebra
package but rather to server as a stable, portable platform for
implementing other algorithms.
NTL is written entirely in C++ and can be easily installed
on most UNIX platforms. Documentation is available online
and also in ASCII files in the package.
[http://www.cs.wisc.edu/~shoup/ntl/]
- NTP
- The Network Time Protocol is used to synchronize
the time of a computer client or server to another server or reference
time source such as a radio or satellite receiver. It provides,
for example,
accuracy typically within a millisecond on LANs relative to a primary
server synchronized to Coordinated Universal Time (UTC) via a GPS
receiver.
NTP is also a software distribution that implements an NTP
client and server.
The NTP distribution consists of several programs including:
- ntpd, an NTP daemon which sets and maintains the system time
in synch with Internet standard time servers;
- ntpq, which is used to query NTP servers;
- ntpdc, which is used to query the ntpd daemon about its
current state;
- ntpdate, which sets the local date and time by polling the
NTP server(s) given as arguments;
- ntptrace, which determines where a given NTP server gets its
time from and follows the chain back to the master time source;
- tickadj, which reads and optionally modifies several
timekeeping-related variables in the running kernel;
- ntptime, which reads and displays time-related kernel variables;
- authspeed, which encrypts a test file and determines the
authentication delay to use in the NTP configuration file;
- authcert, which verifies whether the DES encryption algorithm
is operating correctly; and
- md5, which generates the message digest for a given file
using the RSA Message Digest 5 (MD5) and other algorithms.
A source code distribution of NTP is available.
It is set up to use the GNU configuring tools for the usual
wide variety of platforms.
Quite of bit of documentation about both the protocol and the
software is available, with the software mainly documented in
a set of man pages.
[http://www.eecis.udel.edu/~ntp/]
- number theory
- Related software includes:
- ARIBAS, an interactive interpreter for
big integer and multi-precision floating point arithmetic;
- bc, a calculator language that supports arbitrary
precision numbers and the interactive execution of statements;
- CALC, a calculator program for doing arbitrary
precision integer arithmetic;
- FreeLIP, a package containing functions
for performing arithmetic on arbitrary length signed integers;
- gnubc, a set of programs written using and
for bc;
- KANT, a computer algebra system for sophisticated
computations in algebraic number fields;
- LiDIA, a C++ library
for computational number theory;
- NTL, a C++ library for
doing number theory;
- PARI, a package for performing formal computations
on recursive types at high speeds;
- SIMATH, a computer algebra system focused
mainly on algebraic number theory; and
- ZEN, a toolbox for fast computations in finite
extensions of finite rings.
- Numerical Computation in C and C++
- A list of C or C++ programs and libraries for performing
numerical computations of various types. If you do numerical
analysis and write most of your code in C or C++ it is well worth
your time to give this a look. The list is in the file
numcomp-free-c.gz.
[ftp://usc.edu/pub/C-numanal/]
- numerical analysis environments
- These are integrated systems for performing interactive numerical computations,
especially with matrices. These resemble in one way or another the
Matlab system, more or less. Some are more matrix oriented, some more statistical
oriented, some more graphically oriented, and some just bloody strange.
Available packages include:
- Numerical Integration Toolbox
- A Matlab toolbox for 1-, 2-, and n-D numerical integration.
It contains four general purpose integration routines:
quadg, a high accuracy replacement for QUAD and QUAD8;
quad2g, for 2-D integration over a rectangular region;
quad2ggen, for 2-D integration over a general region; and
quadndg, for n-D integration over a n-D hyper-rectangular region.
The Integration Toolbox can be used on Matlab or on the
freely available Octave which can run
most Matlab m-files.
[http://www.mathworks.com/ftp/integrationv4.shtml]
- Numerical Methods
- Tomasz Plewa's list of resources pertaining to numerical
methods.
[http://www.mpa-garching.mpg.de/~tomek/htmls/
num_meth.html]
[http://www.math.psu.edu/dna/num_methods.html
]
[http://zar.unizar.es/www/num_meth.html
]
[http://www.labyrinth.net.au/~ctrans/tomasz.html
]
- NumPy
- The Numerical extensions to Python add powerful
multi-dimensional array objects to the Python
programming language. These objects give Python the number crunching
power of numeric languages like Matlab an dIDL while maintaining all
of the advantages of Python.
The extensions add two new object types to Python as well as a number
of extensions that take advantage of these objects.
Multidimensional array objects feature efficient arrays of
homogeneous machine data types, an arbitrary number of dimensions,
and sophisticated structural operations.
Universal function objects support mathematical functions on all
Python objects and are designed to be very efficient for array objects.
Simple interfaces to LAPACK,
FFTPACK, and RANLIB
are also supplied.
The NumPy package is a collection of C extension modules which
are available as source code that should easily compile on any
UNIX system.
The documentation includes a reference manual, a tutorial, and some
technical papers available in various formats.
Links to scientific modules developed by third parties are
available on the site.
An extended Python distribution is available via one of these
links. It includes the extension programs as well as various
modules in one package which simplifies the non-trivial task
of compiling and installing the NumPy extensions.
[http://www.sls.lcs.mit.edu/~jjh/numpy/]
- Nuprl
- A computer system which supports the interactive creation of
proofs, formulas, and terms in a formal theory of mathematics.
It can be used to expression concepts associated with
definitions, theorems, theories, books and libraries.
The theory is sensitive to the computational meaning of
terms, assertions, and proofs, and can carry out the actions
used to define that computational meaning.
[http://www.cs.cornell.edu/Info/Projects/NuPrl/nuprl.html]
- NURBS
- Non-Uuniform
Rational B-Splines
are a geometric tool used for graphics and computer-aided design.
They can be used to represent a wide variety of geometric objects
including conic sections and free-form curves and surfaces as well
as more conventional shapes such as straight lines and cubes.
The Manchester NURBS library is a C function library consisting
of a definition of a C structure to represent a NURBS and a large
collection of routines which operate on this structure to perform
many common operations. The source code is available as well as
a manual in PostScript format.
[http://www.man.ac.uk/MVC/research/nurbs/library/]
- NURBS++
- A Non-Uniform Rational B-Spline
library written in C++.
The library includes a NURBS curve class in 3-D (in which the
computation is done in the 4-D homogeneous space).
The capabilities of this class include:
- computation of points and their derivatives along a curve,
- global curve interpolation with or without
specification of first derivative,
- global curve approximation with either least squares fitting or within
an error bound,
- degree elevation of a curve,
- knot manipulation routines,
- decomposition of a curve into its Bezier segments,
- generation of a circular arc starting at user-specified locations,
- reading from and writing to files,
- writing to several types of image files via
ImageMagick,
- writing to PostScript, and
- writing to VRML format.
A NURBS surface class is capable of:
- computation of points and their derivatives along a surface (as well
- as th enormal of the surface at any point),
- global surface interpolation,
- global least squares approximation of a surface,
- degree elevation,
- generation of a surface skin, Gordon surface, sweep surface, and
a surface of revolution of any degree;
- generation of isoparametric curves,
- splitting a surface into Bezier patches,
- reading and writing to files, and
- exportation in VRML, POVRAY and RIB formats.
The package also includes a hierarchical curve and surface class,
some wrapper classes so it can be used with OpenGL,
and a basic NURBS editor.
A source code distribution of NURBS++ is available.
It is written in C++ and is documented in a user's manual
available in either PostScript
or PDF format.
[http://yukon.genie.uottawa.ca/info/soft/nurbs/]
- nuweb
- A literate programming
package that consists of a single program that takes a file
written in a combination of LaTeX
and a programming language and produces a LaTeX file and
a set of compiler-ready files in the programming language
being used.
The features of nuweb include speed, simplicity, multiple
programming languages, indices and cross-references,
and no use of special macros or macro files.
[ftp://ftp.tex.ac.uk/tex-archive/web/nuweb/]
- nv
- An Internet video conferencing tool which was designed to
be as portable as possible (i.e. be able to receive video in
a standard X11 window without requiring special hardware)
and to run over a wide range of network bandwidths.
The first goal was met with a video compression scheme which
could be performed in software at a reasonable speed.
The second by both giving the sender a choice of several resolutions
and between color and black and white, as well as by supplying a
slider switch which allows the precise choice of a maximum bandwidth.
The source code for nv is available as are binaries for
FreeBSD, HP-UX, SGI IRIX, Linux Intel, DEC OSF1, Sun SunOS,
and DEC Ultrix platforms.
The program is briefly documented in a technical report
available in PostScript.
[ftp://parcftp.xerox.com/pub/net-research/]
- nvi
- The new vi editor is the
4.4BSD replacement for
vi.
The source code for this is available as well as a binary
for Linux Intel platforms.
[http://sunsite.unc.edu/pub/Linux/apps/editors/vi/]
- NXLib
- A software environment which allows multicomputer applications,
specifically those developed using the Paragon NX library, to
be developed and simulated on networks of workstations. This
lets networks of workstations be used to develop software which
will be finally run on a Paragon system. The same networks can
also be used as a production environment for some applications,
especially those that can be described as coarse-grained.
The NXLib distribution can be obtained as source code or
in binary form for Sun and Linux Intel platforms. The documentation
is contained within a user's guide and several technical reports
available in PostScript format.
[http://wwwbode.informatik.tu-muenchen.de/~lamberts/
NXLib/]
- Nyquist
- A language for sound synthesis and music composition which
combines the capabilities of score languages that deal with
events and signal processing languages that deal with signals
and synthesis.
It is based on an interactive Lisp
interpreter which makes it both flexible and easy to use.
Instruments are designed by combining functions and can be
called upon to generate a sound by typing a simple expression,
with simple expressions combined into complex ones to create
entire compositions.
A source code distribution of Nyquist is available.
It is written in C and can be compiled and installed on
several UNIX flavors. A patch file is available that allows
it to be compiled on Linux boxes.
A user's manual is available in both
HTML and
PostScript formats.
[http://cec.wustl.edu/~bjl1/nyquist-linux.html]
[http://www.cs.cmu.edu/afs/cs.cmu.edu/user/rbd/www/nyquist.html
]
