955 lines
36 KiB
Plaintext
955 lines
36 KiB
Plaintext
Path: senator-bedfellow.mit.edu!bloom-beacon.mit.edu!gatech!swrinde!elroy.jpl.nasa.gov!netline-fddi.jpl.nasa.gov!csi.jpl.nasa.gov!nobody
|
|
From: mwette@mr-ed.jpl.nasa.gov (Matt Wette)
|
|
Newsgroups: comp.soft-sys.matlab,comp.answers,news.answers
|
|
Subject: comp.soft-sys.matlab FAQ (Frequently Asked Questions)
|
|
Followup-To: comp.soft-sys.matlab
|
|
Date: 23 Nov 1993 09:31:34 -0800
|
|
Organization: Jet Propulsion Laboratory
|
|
Lines: 937
|
|
Approved: news-answers-request@MIT.Edu
|
|
Message-ID: <2cthdm$40v@mr-ed.jpl.nasa.gov>
|
|
Reply-To: mwette@csi.jpl.nasa.gov
|
|
NNTP-Posting-Host: mr-ed.jpl.nasa.gov
|
|
Summary: This article includes product notes and answers to frequently asked
|
|
user questions about the matrix-oriented environment MATLAB, by The
|
|
MathWorks, and products and tools based on or related to MATLAB.
|
|
Xref: senator-bedfellow.mit.edu comp.soft-sys.matlab:3103 comp.answers:2776 news.answers:15030
|
|
|
|
Archive-name: matlab-faq
|
|
Last-modified: 1993/11/23
|
|
Version: $Id: FAQ.in,v 1.2 1993/11/23 17:24:16 mwette Exp $
|
|
|
|
This FAQ is maintained by Matt Wette <mwette@csi.jpl.nasa.gov>.
|
|
The latest version can be retrieved via anonymous ftp from
|
|
|
|
csi.jpl.nasa.gov [128.149.29.4] as /pub/matlab/FAQ.text (plain text)
|
|
or /pub/matlab/FAQ.html (HTML format)
|
|
|
|
Contributions, corrections and suggestions are welcomed.
|
|
|
|
|
|
Last update: Tue Nov 23 09:26:35 PST 1993
|
|
|
|
|
|
|
|
MATLAB Frequently Asked Questions
|
|
=================================
|
|
|
|
|
|
SYNOPSIS
|
|
|
|
|
|
General
|
|
=======
|
|
1) What is MATLAB?
|
|
2) What is the charter for the comp.soft-sys.matlab group?
|
|
3) What commercially available MATLAB-type environments are sold?
|
|
4) What non-commercial MATLAB-type environments exist?
|
|
5) Are there any standards for MATLAB-type tools?
|
|
6) How can I join a MATLAB user group?
|
|
7) Are there any software archives?
|
|
8) Are there any publications related to MATLAB?
|
|
|
|
MATLAB/SIMULINK Product Information
|
|
===================================
|
|
9) What's new in MATLAB 4.0?
|
|
10) How does MATLAB perform on machine X?
|
|
11) What is SIMULINK (alias Simulab)?
|
|
12) What toolboxes are currently available from The MathWorks?
|
|
13) Can I use C and Fortran programs with MATLAB?
|
|
14) How do I contact The MathWorks about MATLAB via email?
|
|
|
|
MATLAB User Questions
|
|
=====================
|
|
15) How can I change the default window size, colors, etc. in MATLAB 4?
|
|
16) How can I import MATLAB graphics into my Framemaker, TeX, etc. document?
|
|
17) Is there a topical help function, like `apropos'?
|
|
18) Why am I finding all these undocumented functions (like COMET) in MATLAB?
|
|
19) Has anybody any information about the matlab function `system_dependent'?
|
|
20) How can I get the parser to accept a dummy reference without an error?
|
|
21) How do I get the plot command to cycle through line-types?
|
|
22) Can I use `dbup' and `dbdown' within a function?
|
|
23) Is there a GNU emacs editing mode for MATLAB?
|
|
24) What is the sign convention used in MATLAB's FFT routines?
|
|
25) Is there any MATLAB software for wavelets?
|
|
26) Is there any MATLAB software for fuzzy logic?
|
|
27) Is there any MATLAB software for communications?
|
|
28) Is there a MATLAB interface to Mathematica?
|
|
29) Why was `fsolve' removed from MATLAB Version 4?
|
|
30) Are there any published books on, or relating to, MATLAB?
|
|
|
|
Quick Little MATLAB Hacks
|
|
=========================
|
|
31) How can I initialize a this low rank matrix easily?
|
|
32) How can I load-from or save-to a file whose name is in a string variable?
|
|
33) How can I store the result of `!ls *.dat' in a variable?
|
|
34) How can I make a variable global from within a function?
|
|
|
|
MATLAB on the PC
|
|
================
|
|
35) What can I do when MATLAB tells me there is not enough environment space?
|
|
|
|
Xmath / MatrixX Product Information.
|
|
====================================
|
|
36) What is Xmath?
|
|
37) Are there any publications related to MatrixX?
|
|
38) Are there any e-mail addresses related to MatrixX/Xmath?
|
|
39) What other modules are available from ISI?
|
|
|
|
Xmath User Questions
|
|
====================
|
|
40) Is it possible to derive new classes in XMath?
|
|
|
|
|
|
|
|
|
|
General
|
|
=======
|
|
|
|
1) What is MATLAB?
|
|
|
|
MATLAB is the name used to refer to the class of matrix cal-
|
|
culator environments derived from the first, called MATLAB.
|
|
MATLAB was developed by Cleve Moler in the late 1970s at the
|
|
University of New Mexico and other locations with support
|
|
from the National Science Foundation. Since then, many
|
|
work-a-likes have been developed or are in development com-
|
|
mercially, in government and university labs, and so forth.
|
|
|
|
The name of the product available from MathWorks is
|
|
"MATLAB", not Matlab, Pro-MatLab, etc. Note that MathWorks
|
|
holds a registered trademark on the uppercase version of
|
|
MATLAB.
|
|
|
|
In this document, Matlab may refer to the collective set of
|
|
MATLAB-based environments or it may refer to the current im-
|
|
plementation developed by MathWorks, Inc. In general, these
|
|
MATLAB-based environments are not source-language compati-
|
|
ble.
|
|
|
|
2) What is the charter for the comp.soft-sys.matlab group?
|
|
|
|
The newsgroup 'comp.soft-sys.matlab' is a forum for discuss-
|
|
ing issues related to the use of MATLAB, the scientific cal-
|
|
culation and visualization package from MathWorks Inc. This
|
|
includes discussion of similar software packages which are
|
|
also derived from the original `Classic MATLAB', such as
|
|
Xmath from Integrated Systems Inc.
|
|
|
|
Appropriate discussion in the group will include both gen-
|
|
eral Matlab issues and platform-specific questions, and dis-
|
|
cussion comparing MATLAB to other systems.
|
|
|
|
3) What commercially available MATLAB-type environments are sold?
|
|
|
|
In alphabetical order:
|
|
|
|
`CLAM' from Scientific Computing Associates, Inc.
|
|
|
|
246 Church Street, Suite 307
|
|
New Haven, CT 06510
|
|
Tel: 203-777-7442
|
|
Fax: 203-776-4074
|
|
|
|
`Ctrl-C' from Systems Control Technology, Inc.
|
|
|
|
CAE Systems Department
|
|
2300 Geng Road
|
|
Palo Alto, CA 94303
|
|
Tel: 800-227-1910
|
|
Tel: 415-494-2233
|
|
Fax: 415-496-6595
|
|
|
|
`MATLAB' from The MathWorks, Inc.
|
|
|
|
Cochituate Place
|
|
24 Prime Park Way
|
|
Natick, MA 01760
|
|
Tel: 508-653-1415
|
|
Fax: 508-653-2997.
|
|
Email: info@mathworks.com
|
|
|
|
`O-MATRIX' from Harmonic Software, Inc.
|
|
|
|
12223 Dayton Avenue North
|
|
Seattle, WA 98133
|
|
Tel: 206-367-8742
|
|
Fax: 206-367-1067
|
|
Email: harmonic@world.std.com
|
|
|
|
`Xmath' from Integrated Systems, Inc.
|
|
|
|
3260 Jay St.
|
|
Santa Clara, CA 95054-3309
|
|
Tel: (408) 980-1500
|
|
Fax: (408) 980-0400
|
|
Email: xmath-info@isi.com
|
|
|
|
4) What non-commercial MATLAB-type environments exist?
|
|
|
|
In alphabetical order:
|
|
|
|
`Caesy' is being developed by Matt Wette
|
|
(mwette@csi.jpl.nasa.gov) at the Jet Propulsion Laboratory.
|
|
This will be released to COSMIC soon. It will provide data
|
|
structures, conversion to C-code, and many other features.
|
|
See
|
|
|
|
M.Wette, "Caesy: A Computer-Aided Engineering System"
|
|
Proc. 1992 Symp. on Computer-Aided Control System Design
|
|
Napa, CA, March 1992
|
|
|
|
`Mat/C' developed at Lawrence Livermore National Labora-
|
|
tories by Don Gavel. This is not publically available.
|
|
|
|
`Matcalc', by M.Gerberg and E.J. Moore, University of New
|
|
South Wales, Australia. It is available via anonymous ftp
|
|
from
|
|
|
|
draci.cs.uow.edu.au in /netlib/matcalc/
|
|
csi.jpl.nasa.gov in /pub/matlab/matcalc/
|
|
|
|
`MaTX', an interpreter and compiler, developed at Tokyo In-
|
|
stitute of Technology. See
|
|
|
|
M. Koga and K. Furuta, "MaTX: A High-Performance Programming
|
|
Language (Interpreter and Compiler) for Scientific and
|
|
Engineering Computation," Proc. 1992 Symp. on Computer-Aided
|
|
Control System Design, Napa, CA, March 1992
|
|
|
|
`MEDAL' developed at the University of Waterloo by Grantham
|
|
Pang (pang@excel2.uwaterloo.ca). This has the same command
|
|
language as MATLAB, but includes a knowledge-based expert
|
|
system development facility. It is available for academic
|
|
and research users via anonymous. You'll need to get a pro-
|
|
gram password from the author to operate it (no sources in-
|
|
cluded). It's available via anonymous ftp from
|
|
|
|
excel2.uwaterloo.ca [129.97.86.13] in /pub/
|
|
|
|
See
|
|
|
|
Pang, G.K.H.,"Knowledge-based Control System Design", in Recent Advances
|
|
in Computer-Aided Control Systems Engineering, Jamshidi, M and Herget,
|
|
C.J. (ed.), Elsevier Science Publishers, 1992.
|
|
|
|
Pang, G.K.H., "A Knowledge Environment for an Interactive Control System
|
|
Design Package", Automatica, Vol. 28. No. 3, pp. 473-491, May 1992.
|
|
|
|
`Octave', written at the University of Texas
|
|
(jwe@che.utexas.edu), is available via anonymous ftp from
|
|
|
|
ftp.che.utexas.edu as /pub/octave/octave-?.?.tar.Z
|
|
|
|
`RLaB', written by Ian Searle (ians@eskimo.com), is free
|
|
software (in the GNU copyleft sense). It is currently
|
|
available via anonymous ftp from
|
|
|
|
csi.jpl.nasa.gov in /pub/matlab/RLaB
|
|
evans.ee.adfa.oz.au in /pub/RLaB
|
|
|
|
5) Are there any standards for MATLAB-type tools?
|
|
|
|
There is an IFAC/IEEE-CSS Working Group developing standards
|
|
and guidelines for these tools. A proposed standard command
|
|
language was developed, is described in the document "Com-
|
|
mand Language Standard for CACSD Software" and is available
|
|
from
|
|
|
|
Magnus Rimvall
|
|
Control Systems Laboratory, GE-CRD
|
|
Schenectady, NY 12301
|
|
|
|
6) How can I join a MATLAB user group?
|
|
|
|
To join the user group, send your name, affiliation and ad-
|
|
dress to:
|
|
|
|
matlab-users-request@mcs.anl.gov
|
|
|
|
For European user groups, contact:
|
|
|
|
France: Alain Baron
|
|
phone: 33/1 45 34 23 91
|
|
fax: 33/1 45 07 08 06
|
|
Germany: Dr. Ingrid Bausch-Gall
|
|
phone: 49/89 323 2625
|
|
fax: 49/89 323 1063
|
|
Sweden: Svante Littmarck
|
|
phone: 46/8 15 30 22
|
|
fax: 48/8 15 76 35
|
|
email: info@comsol.se
|
|
|
|
Switzerland: Carl Bergstrom
|
|
phone: 031/961 70 11
|
|
fax: 031/961 12 82
|
|
email: comsol@clients.switch.ch
|
|
|
|
UK: Peter Campbell
|
|
phone: +44-223-421920
|
|
fax: +44-223-421921
|
|
|
|
7) Are there any software archives?
|
|
|
|
Yes. MATLAB User Group software archive contains more than
|
|
1MB of user-contributed code. This archive is located on
|
|
NETLIB server of Oak Ridge National Laboratories. To learn
|
|
more, send following message:
|
|
|
|
send index
|
|
send index from matlab
|
|
to:
|
|
|
|
netlib@ornl.gov
|
|
|
|
For access from Europe, try the duplicate collection in
|
|
Oslo:
|
|
|
|
Internet: netlib@nac.no
|
|
EARN/BITNET: netlib%nac.no@norunix.bitnet
|
|
X.400: s=netlib; o=nac; c=no;
|
|
EUNET/uucp: nac!netlib
|
|
For the Pacific, try netlib@draci.cs.uow.edu.au located at
|
|
the University of Wollongong, NSW, Australia.
|
|
|
|
The MathWorks maintains the archive on the anonymous ftp
|
|
server ftp.mathworks.com [144.212.100.10]. This site con-
|
|
tains a "best of" copy of the NETLIB archive as well as oth-
|
|
er user-contributed, and MathWorks contributed software and
|
|
documentation. If you are interested in submitting software
|
|
to the archive pick up the file README.incoming from the ar-
|
|
chive or send e-mail to drea@mathworks.com
|
|
|
|
There is a renegade archive at csi.jpl.nasa.gov
|
|
[128.149.29.4], in /pub/matlab. This is stocked with a
|
|
mish-mash of stuff you may not find on the other archives
|
|
(e.g., free MATLAB-look-a-likes).
|
|
|
|
8) Are there any publications related to MATLAB?
|
|
|
|
Yes, Math Works Inc. publishes a quarterly magazine called
|
|
MathWorks Newsletter, giving info. on products (new ver-
|
|
sions, releases, toolboxes), matlab user group, matlab short
|
|
courses, related texts etc. To subscribe to the newsletter,
|
|
send email with your snail mail address to
|
|
subscribe@mathworks.com.
|
|
|
|
|
|
|
|
MATLAB/SIMULINK Product Information
|
|
===================================
|
|
|
|
9) What's new in MATLAB 4.0?
|
|
|
|
from John Little ...
|
|
|
|
Here's the "high-level" summary of the major new additions:
|
|
|
|
* Object-based graphics facility
|
|
* 3-D color scientific visualization abilities
|
|
* Animation
|
|
* Sound output capability
|
|
* M-file debugging facilities
|
|
* Low-level file I/O functions
|
|
* Graphical user interface controls (GUI widget set)
|
|
* Sparse matrix support
|
|
* An improved help system
|
|
* Interpreter and graphics speed improvements
|
|
* A new External Interface library (MEX-files, engine, MAT-files)
|
|
* Better documentation (in the eyes of the beholder, I imagine :-) )
|
|
* Lots of other smaller improvements..
|
|
|
|
10) How does MATLAB perform on machine X?
|
|
|
|
LINPACK benchmarks in MATLAB (reported by The MathWorks):
|
|
|
|
machine KFLOPS (LINPACK)
|
|
======= ================
|
|
Macintosh (8MHz 68000) 3
|
|
PC/AT (6.0MHz/80286/EGA) 15
|
|
PC/XT (4.7MHz/8088/CGA) 17
|
|
AT&T 6300 (8MHz/8086) 29
|
|
Macintosh II (68020/68881) 85
|
|
MicroVAX II (VMS/D_floating) 140
|
|
Macintosh IIcx (68030/68882) 168
|
|
HP 9000/Series 350 190
|
|
80386/80387 (20MHz, 386-MATLAB) 232
|
|
Macintosh IIci (25MHz 68030/68882) 239
|
|
VAXstation 3100 (VMS/D_floating) 365
|
|
HP 9000/400 (68030) 500
|
|
80486-based PC (33M Hz) 1300
|
|
HP 9000/425 (68040 chip) 1400
|
|
Macintosh Quadra 700 1500
|
|
Sun SPARCstation 1 1500
|
|
DECstation 3100 1600
|
|
SGI Indigo 2400
|
|
Sun SPARCstation 2 2900
|
|
Convex C1 3700
|
|
IBM RS/6000 7000
|
|
HP 9000/700 7400
|
|
Cray X-MP 71000
|
|
Cray X-MP on a 500-by-500 matrix 135000
|
|
|
|
Other numbers (reported by users):
|
|
|
|
80486-DX2 PC @66MHz 3121 (k.hari@ieee.org)
|
|
|
|
11) What is SIMULINK (alias Simulab)?
|
|
|
|
SIMULINK is an interactive system for the nonlinear simula-
|
|
tion of dynamical systems. It is a graphical, mouse-driven
|
|
program that allows systems to be modelled by drawing a
|
|
block diagram on the screen. It can handle linear, non-
|
|
linear, continuous-time, discrete-time, multivariable, and
|
|
multirate systems. SIMULINK runs on workstations using X-
|
|
windows, under MicroSoft Windows on the PC, and on the Ma-
|
|
cintosh. It takes full advantage of windowing technology,
|
|
including pull-down windows and mouse interactions. SIMULINK
|
|
is fully integrated with MATLAB, and, together with MATLAB
|
|
and the Control System Toolbox, forms a complete control
|
|
system design and analysis environment.
|
|
|
|
12) What toolboxes are currently available from The MathWorks?
|
|
|
|
The following list includes toolboxes currently offered by
|
|
The MathWorks. For more info check
|
|
|
|
ftp.mathworks.com in /pub/product-info
|
|
|
|
Signal Processing Toolbox.
|
|
|
|
This is a toolbox for digital signal processing (time series
|
|
analysis). It includes functions for the design and
|
|
analysis of digital filters, like Butterworth, Elliptic, and
|
|
Parks-McClellan, and for FFT analysis (power spectrum esti-
|
|
mation). It also includes some 2-dimensional signal pro-
|
|
cessing capabilities.
|
|
|
|
Control System Toolbox.
|
|
|
|
This is a toolbox for control system design and analysis.
|
|
It supports transfer function and state-space forms
|
|
(continuous/discrete time, frequency domain). Function for
|
|
step, impulse, arbitrary input responses, as well as Bode,
|
|
Nyquist, and Nichols plots. Design with root-locus, pole-
|
|
placement, and LQR optimal control.
|
|
|
|
System Identification Toolbox.
|
|
|
|
This is a toolbox for parametric modelling. Identified
|
|
models are in transfer function form (either z-transform or
|
|
Laplace transform) and state-space form (e.g., ARMA models
|
|
or Box-Jenkins models).
|
|
|
|
Optimization Toolbox.
|
|
|
|
This is a toolbox for linear and nonlinear optimization and
|
|
supports unconstrained and constrained minimization,
|
|
minimax, nonlinear least squares, multi-objective, and
|
|
semi-infinite optimization, linear programming, quadratic
|
|
programming and the solution of non-linear equations.
|
|
|
|
Spline Toolbox.
|
|
|
|
This is a toolbox for working with splines and is typically
|
|
used for curve fitting, solution of function equations and
|
|
functional approximation.
|
|
|
|
Robust-Control Toolbox.
|
|
|
|
This is a toolbox for robust control system design and sup-
|
|
ports LQG/loop transfer recovery, H2, H0, and mu- control
|
|
synthesis, singular value frequency response, and model
|
|
reduction.
|
|
|
|
Neural Net Toolbox.
|
|
|
|
This is a toolbox for designing and simulating neural net-
|
|
works and supports implementation of the perceptron learning
|
|
rule, the Widrow-Hoff rule, and several variations of the
|
|
backpropagation rule. Transfer functions included are hard
|
|
limit, linear, logistic & hypertangent sigmoid.
|
|
|
|
Delta Toolbox.
|
|
|
|
This is a toolbox for analysis using the delta transform, an
|
|
approach to unifying continuous and discrete systems theory
|
|
without use of the Z-transform. It is available free to
|
|
purchasers of "Digital Control and Estimation: A Unified Ap-
|
|
proach," by Graham Goodwin and Rick Middleton.
|
|
|
|
Image Processing Toolbox.
|
|
|
|
The Image Processing Toolbox provides an environment for im-
|
|
age processing and analysis. Images are matrices
|
|
(surprised?). Functions include linear and nonlinear
|
|
filtering; image restoration; image enhancement; image
|
|
analysis and statistics; color, geometric, and morphological
|
|
operations 2-D transforms; and 2D FIR filter design and fre-
|
|
quency response.
|
|
|
|
Symbolic Math Toolbox.
|
|
|
|
The Symbolic Math Toolbox contains functions for symbolic
|
|
algebra, exact linear algebra, variable precision arithmet-
|
|
ic, equation solving, and special mathematical functions.
|
|
Its underlying computational engine is the kernel of Maple.
|
|
The Extended Symbolic Math Toolbox augments the functionali-
|
|
ty to include Maple programming features and specialized li-
|
|
braries.
|
|
|
|
Statistics Toolbox.
|
|
|
|
The Statistics Toolbox provides statistical data analysis,
|
|
modeling, and Monte Carlo simulation; building-blocks for
|
|
creating your own special-purpose statistical tools; and GUI
|
|
tools for exploring fundamental concepts in statistics and
|
|
probability. Functionality covers descriptive, inferential,
|
|
and graphical statistics, and linear models as well as in-
|
|
teractive graphics for dynamic visualization of functions,
|
|
data, and probability distributions.
|
|
|
|
13) Can I use C and Fortran programs with MATLAB?
|
|
|
|
MATLAB's MEX-file facility allows user to use C and Fortran
|
|
subroutines as MATLAB m-files. It is also possible to use
|
|
MATLAB as a computational engine for C/Fortran subroutines.
|
|
|
|
14) How do I contact The MathWorks about MATLAB via email?
|
|
|
|
Here you go ...
|
|
|
|
* support@mathworks.com technical support
|
|
* suggest@mathworks.com product enhancement suggestions
|
|
* bugs@mathworks.com bug reports
|
|
* doc@mathworks.com documentation error reports
|
|
* register@mathworks.com user and product registration
|
|
* subscribe@mathworks.com subscribing user registration
|
|
* info@mathworks.com sales, pricing, general info.
|
|
* netlib@ornl.gov software archive contact
|
|
* digest@mcs.anl.gov user group
|
|
|
|
|
|
|
|
MATLAB User Questions
|
|
=====================
|
|
|
|
15) How can I change the default window size, colors, etc. in MATLAB 4?
|
|
|
|
|
|
from serr15@liverpool.ac.uk ...
|
|
|
|
Try something like the following in your `startup.m' file:
|
|
|
|
set(0,'DefaultFigurePosition',[5 5 505 405])
|
|
set(0,'DefaultFigureColor',[0,0,0]) %% N.B this has side effects.
|
|
set(0,'DefaultAxesFontName','times')
|
|
set(0,'DefaultTextFontName','times')
|
|
set(0,'DefaultAxesFontSize',12)
|
|
set(0,'DefaultTextFontSize',12)
|
|
|
|
16) How can I import MATLAB graphics into my Framemaker, TeX, etc. document?
|
|
|
|
The MATLAB (version 4) print command provides a "-deps" ar-
|
|
gument which provides a Encapsulated PostScript file of your
|
|
plot. Some people have reported various problems getting
|
|
this stuff to work. Some suggestions:
|
|
|
|
Removing the last line "%%EOF" from the eps-file.
|
|
|
|
Use the the pstoepsi filter from Doug Crabill
|
|
(dgc@cs.purdue.edu).
|
|
|
|
Use "bbps" and ghostscript. "bbps.shar" is available via
|
|
anonymous ftp on "csi.jpl.nasa.gov". You'll need to get
|
|
GhostScript from your nearest GNU ftp site.
|
|
|
|
[This area needs more work :). ed.]
|
|
|
|
17) Is there a topical help function, like `apropos'?
|
|
|
|
Yes. The function you're looking for is `lookfor' (in
|
|
MATLAB 4).
|
|
|
|
>> lookfor fourier
|
|
|
|
FFT Discrete Fourier transform.
|
|
FFT2 Two-dimensional Fast Fourier Transform.
|
|
IFFT Inverse discrete Fourier transform.
|
|
IFFT2 Two-dimensional inverse discrete Fourier transform.
|
|
FOURIER Graphics demo of Fourier series expansion.
|
|
DFTMTX Discrete Fourier transform matrix.
|
|
|
|
>>
|
|
|
|
18) Why am I finding all these undocumented functions (like COMET) in MATLAB?
|
|
|
|
from Cleve Moler ...
|
|
|
|
Almost everything in the "demos" directory is not described
|
|
in the User's Guide. There are lots of goodies there. In
|
|
4.0, the demos are best place to see examples of Handle
|
|
Graphics.
|
|
|
|
There are other undocumented functions in directories other
|
|
than demos. Some of them are "worker" functions that are
|
|
unlikely to be used directly; they are simply called by oth-
|
|
er functions. A few, like COMET and COMET3, were actually
|
|
written after the User's Guide had been sent to the printer.
|
|
|
|
19) Has anybody any information about the matlab function `system_dependent'?
|
|
|
|
from John Little (w/editing) ...
|
|
|
|
`system_dependent' is an unpublished function that is used
|
|
for a variety of crufty things. It will most certainly
|
|
change from time to time and possible even go away complete-
|
|
ly. For anybody curious about it, here is what it does in
|
|
MATLAB 4.0 on SPARCstations:
|
|
|
|
|
|
system_dependent(1) deals with the MATLAB-ACSL interface. ACSL
|
|
is a simulation language that MATLAB can talk
|
|
to. See ACSL.M for more information.
|
|
|
|
system_dependent(2,0) turns off command-line editing.
|
|
system_dependent(2,1) turns it back on.
|
|
|
|
system_dependent(3) is unused.
|
|
|
|
system_dependent(4,i,j) is used to program the command-line editing
|
|
keys. See CEDIT.M for more information.
|
|
|
|
system_dependent(5) enables core dumps in the event of seg faults.
|
|
Normally MATLAB tries to catch seg faults and
|
|
"continue".
|
|
|
|
system_dependent does different things in MATLAB 3.5 and
|
|
other platforms.
|
|
|
|
20) How can I get the parser to accept a dummy reference without an error?
|
|
|
|
Adopted from post by Jim Tung ...
|
|
|
|
MATLAB parses code to look for syntax errors. When the
|
|
parser encounters a name with 2 or fewer arguments, it lets
|
|
them pass since they might be a variable with indices. If
|
|
it encounters a name with 3 or more arguments, MATLAB knows
|
|
it cannot be a variable, so the error message is returned.
|
|
If you don't want the parser to snag the function, specify
|
|
one with 2 or fewer arguments.
|
|
|
|
21) How do I get the plot command to cycle through line-types?
|
|
|
|
From Chuck Packard <cpackard@mathworks.com> ...
|
|
|
|
MATLAB v4.1 has a an axis property LineStyleOrder for this.
|
|
Monochrome users can tell MATLAB to always use white lines
|
|
and cycle through their favorite line styles with the com-
|
|
mands:
|
|
|
|
set( 0, 'DefaultAxesColorOrder', [1 1 1] )
|
|
set( 0, 'DefaultAxesLineStyleOrder', '-|:|--' )
|
|
|
|
These commands can be put in your startup.m to always give
|
|
you styled lines.
|
|
|
|
22) Can I use `dbup' and `dbdown' within a function?
|
|
|
|
Derived from post's of lara@mrisun.med.yale.edu and
|
|
jlittle@mathworks.com ...
|
|
|
|
MATLAB wasn't designed to be used this way. But, if you
|
|
don't reference any variables between your calls to `dbup'
|
|
and `dbdown' (i.e., you just use `save', `who', `dir', etc),
|
|
it should work. Otherwise, you may well run into problems.
|
|
If you `dbup' while in a function, you change the workspace
|
|
context while continuing execution of the original function.
|
|
This means that subsequent references to variables will be
|
|
bound to variables in a different workspace. Since the
|
|
internal p-code uses integers as variable identifiers, you
|
|
will get a random attachment to these different variables.
|
|
At best, you'll get random results. At worst you might seg
|
|
fault if you exceed the number of available identifiers.
|
|
|
|
23) Is there a GNU emacs editing mode for MATLAB?
|
|
|
|
A GNU emacs `matlab-mode' is available via anonymous ftp
|
|
from
|
|
|
|
csi.jpl.nasa.gov as pub/matlab/util/matlab-mode.el
|
|
|
|
24) What is the sign convention used in MATLAB's FFT routines?
|
|
|
|
The FFT in MATLAB is defined as sum(x(i)*exp(-j*i*k/N)) and
|
|
not sum(x(i)*exp(j*i*k/N)). The first version is tradition-
|
|
ally used by engineers, the second version by mathemati-
|
|
cians. Since MATLAB was written by an engineer (John Lit-
|
|
tle), the engineering approach was used.
|
|
|
|
25) Is there any MATLAB software for wavelets?
|
|
|
|
Contact Carl Taswell <taswell@sccm.stanford.edu> is working
|
|
on a wavelet toolbox. The toolbox and associated papers are
|
|
available via anonymous ftp from
|
|
|
|
simplicity.stanford.edu in /pub/taswell
|
|
|
|
A newer version should be available soon.
|
|
|
|
Also, Jeff Kantor <jeffrey.kantor@nd.edu> is distributing a
|
|
wavelet toolbox. It is available via anonymous ftp from
|
|
|
|
control.cheg.nd.edu in /pub/wavelets/wavetools1_1.tar
|
|
|
|
The toolbox, rice-wlet-tools-1.1, a collection of MATLAB
|
|
"mfiles" and "mex" files for twoband and M-band filter
|
|
bank/wavelet analysis, is available via anonymous ftp from
|
|
|
|
cml.rice.edu in /pub/dsp/{software,papers}
|
|
|
|
Contact Ramesh Gopinath <ramesh@dsp.rice.edu>.
|
|
|
|
26) Is there any MATLAB software for fuzzy logic?
|
|
|
|
A.Lotfi <lotfia@s1.elec.uq.oz.au> has developed a Fuzzy
|
|
Inference Systems Toolbox. It is available via anonymous
|
|
ftp from
|
|
|
|
ftp.mathworks.com as /pub/contrib/misc/fuzzy_inference_systems.sh
|
|
or /pub/contrib/misc/pc_fuzzy_inference_systems.sh
|
|
|
|
A Fuzzy-Control Toolbox has been developed by Bernhard
|
|
Kaemmpf <kaempf@ifr.luftfahrt.uni-stuttgart.de>. Send him
|
|
email if you are interested in obtaining the software.
|
|
(Sounds like he is willing to give it away.)
|
|
|
|
Jyh-Shing Roger Jang <jang@diva.berkeley.edu> has provided a
|
|
few routines for demonstrating parameterizing membership
|
|
functions (MF) and learning in fuzzy inference systems
|
|
(FIS). The file fuzzdemo.tar.Z is available via anonymous
|
|
ftp from
|
|
|
|
csi.jpl.nasa.gov in /pub/matlab/contrib/
|
|
|
|
27) Is there any MATLAB software for communications?
|
|
|
|
Mehmet Zeytinoglu <mzeytin@ee.ryerson.ca> has written a
|
|
MATLAB toolbox for communications. It is available via
|
|
anonymous ftp from
|
|
|
|
ftp.mathworks.com as /pub/contrib/misc/comm_tbx.tar
|
|
|
|
28) Is there a MATLAB interface to Mathematica?
|
|
|
|
Yes. WRI has developed a free MATLAB-Mathematica interface.
|
|
It is available via anonymous ftp from
|
|
|
|
mathsource.wri.com as /pub/WhatsNew/matlab2math.tar.Z (Unix)
|
|
or /pub/WhatsNew/matlab2math.sea.hqx (Mac)
|
|
or /pub/WhatsNew/matlab2math.zip (Windows) ?
|
|
or via email via "send 0205-951" to mathsource@wri.com.
|
|
|
|
29) Why was `fsolve' removed from MATLAB Version 4?
|
|
|
|
The algorithms used by fsolve were not numerically well
|
|
behaved. MathWorks did not feel that it met the standards
|
|
require for approved software. The version of FSOLVE in the
|
|
Optimization Toolbox is recommended. If your site doesn't
|
|
still have the 3.5 version, you can get it via anonymous ftp
|
|
from
|
|
|
|
ftp.mathworks.com as /pub/contrib/optim/fsolve35.tar
|
|
|
|
30) Are there any published books on, or relating to, MATLAB?
|
|
|
|
There is a list of published book available via anonymous
|
|
ftp from
|
|
|
|
csi.jpl.nasa.gov as /pub/matlab/matlab-books
|
|
|
|
|
|
|
|
Quick Little MATLAB Hacks
|
|
=========================
|
|
|
|
31) How can I initialize a this low rank matrix easily?
|
|
|
|
Here's "Tony's trick", attributed to Tony Booer of Schlum-
|
|
berger:
|
|
|
|
To initialize a matrix with values "a" in the first row and
|
|
values "b" in the second row, do the following:
|
|
|
|
[a(1,ones(1,m)) ; b(1,ones(1,m))]
|
|
|
|
32) How can I load-from or save-to a file whose name is in a string variable?
|
|
|
|
|
|
name = 'xyz.mat';
|
|
eval(['save ', name]);
|
|
eval(['load ', name]);
|
|
|
|
33) How can I store the result of `!ls *.dat' in a variable?
|
|
|
|
|
|
[stat, list] = unix('ls *.dat');
|
|
The variable `stat' contains the return status, the variable
|
|
`list' contains the output.
|
|
|
|
34) How can I make a variable global from within a function?
|
|
|
|
You can in MATLAB 4. The following hack is from Laura Nee-
|
|
dles <lohrah@csi.jpl.nasa.gov> and Mike Kantner
|
|
<rainbow@csi.jpl.nasa.gov>. Define the script file
|
|
`mkglobal.m', containing
|
|
|
|
function [] = mkglobal(var)
|
|
% MKGLOBAL mkglobal(var) - make var a global variable
|
|
if ~exist('mkglobal_var'), mkglobal_1; end;
|
|
mkglobal_var = var; mkglobal_2
|
|
|
|
Define the script file `mkglobal_1.m' as
|
|
|
|
global mkglobal_var
|
|
|
|
Define the script file `mkglobal_2.m' as
|
|
|
|
eval(['global ', mkglobal_var]);
|
|
|
|
|
|
|
|
MATLAB on the PC
|
|
================
|
|
|
|
35) What can I do when MATLAB tells me there is not enough environment space?
|
|
|
|
This usually happens if in the matlab path you include
|
|
greater that 4 or 5 paths. One solution is to increase your
|
|
environment space by adding the following command in your
|
|
config.sys file:
|
|
|
|
shell=c:\dos\command.com /e:nnnnn /p
|
|
|
|
where nnnnn is the number of bytes you use for environment
|
|
memory. It varies from 256 bytes to 32768 bytes(32Kbytes).
|
|
Usually, 5000 bytes can solve your problem. (The /p command
|
|
is used so that the autoexec.bat file runs when you boot
|
|
your computer.)
|
|
|
|
|
|
|
|
Xmath / MatrixX Product Information.
|
|
====================================
|
|
|
|
36) What is Xmath?
|
|
|
|
from mesaros@isi.com ...
|
|
|
|
Xmath is an interactive mathematics, scripting, and graphics
|
|
environment for X Window workstations. It has features
|
|
which represent a significant improvement on matlab-type
|
|
software tools, including:
|
|
|
|
* Object-oriented scripting language.
|
|
* "Point-and-click" color graphics.
|
|
* Visual debugging tool.
|
|
* LNX and C-callable libraries.
|
|
* Programmable MOTIF GUI layer.
|
|
|
|
Xmath from Integrated Systems Inc. is available on the In-
|
|
ternet via FTP from isi.com. If you would like to down-load
|
|
Xmath to view the Xmath Interactive demo, do the following:
|
|
|
|
From the UNIX/Shell environment, type:
|
|
ftp isi.com (if the host is unknown, try ftp 192.73.222.1)
|
|
When asked for name/user, type:
|
|
anonymous
|
|
When asked for the password, simply type your e-mail address.
|
|
|
|
Once your e-mail address is accepted, and if the maximum
|
|
number of ftp clients has not been exceeded, the connection
|
|
will be made and a list of instructions will appear. Simply
|
|
follow that list of instructions to transfer a copy of Xmath
|
|
to your system.
|
|
|
|
37) Are there any publications related to MatrixX?
|
|
|
|
Yes, ISI publishes a quarterly magazine called Response
|
|
Times that gives information on products (new ver- sions,
|
|
releases, modules), user conference, classes, and a Techni-
|
|
cal Support Corner where they answer user questions.
|
|
|
|
Also, ISI has an annual Users Conference. The viewgraph
|
|
presentations from this conference are available. The next
|
|
conference in March 15-17, 1993.
|
|
|
|
38) Are there any e-mail addresses related to MatrixX/Xmath?
|
|
|
|
Yes. Some are:
|
|
|
|
* support@isi.com tech support for ISI MatrixX products
|
|
(408)980-1590 ext. 321
|
|
* info@isi.com product literature requests
|
|
* kate@isi.com contributions to Response Times Mag
|
|
|
|
39) What other modules are available from ISI?
|
|
|
|
|
|
* MatrixX/XMath
|
|
* Robust Control Module
|
|
* Optimization Module
|
|
* Model Reduction Module
|
|
* Digital Signal Processing Module
|
|
* System Identification Module
|
|
|
|
* System_Build
|
|
* RT/Expert System Block
|
|
* RT/Fuzzy Logic Block
|
|
* Interactive Animation
|
|
* AutoCode (C,FORTRAN, Ada)
|
|
* Automatic Documentation Generation
|
|
|
|
3rd Party Packages
|
|
|
|
* ADAPTx Automated System Identification Software
|
|
|
|
Real Time Execution
|
|
|
|
* AC-100 Product for Hardware in the Loop Simulations
|
|
|
|
ISI recently merge with the Software Component Group that
|
|
makes and sells the PSOS+ real time operating system and
|
|
development tools.
|
|
|
|
|
|
|
|
Xmath User Questions
|
|
====================
|
|
|
|
40) Is it possible to derive new classes in XMath?
|
|
|
|
From Alexandra Schmidt <aliki@isi.com> ...
|
|
|
|
Xmath does not currently allow you to 'derive' new subc-
|
|
lasses from the built-in ones (dynamic systems, parameter-
|
|
dependent matrices, strings and string matrices, polynomi-
|
|
als, "special matrices", etc.) However, a number of our
|
|
users have used the list object to create compound objects
|
|
containing different kinds of built-in objects, then used
|
|
the resulting list-based object for more complex data model-
|
|
ing. Your question echoes a request we've heard a number of
|
|
times and is a high priority for our future development, so
|
|
keep an eye out. . .
|
|
|
|
|
|
$Id: FAQ.in,v 1.2 1993/11/23 17:24:16 mwette Exp $
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|