Re: Matlab File Format

[A+A Adler]

On Fri, 18 Jun 1999, John W. Eaton wrote:
> As I recall, Matcom supports reading and writing Matlab version 5 data
> files.  Does anyone know if the people at the MathTools reverse
> engineered the format and if so, whether they expect to be sued by the
> MathWorks?

Here's how it works: (from my oct 1997 post here)
(some directory locations have changed since then!)

ftp.mathworks.com/pub/tech-support/library/matlab5/bin/readmemat.txt

Basically, it's a "free" library with appropriate functions to
manipulate .mat files. You get the *.h and *.so files
for your architecture at

ftp://ftp.mathworks.com/pub/tech-support/library/matlab5/extern/lib/YOUR_ARCH

There may be examples in (I took a quick look but nothing seemed appropriate)
ftp://ftp.mathworks.com/pub/tech-support/library/matlab5/extern/examples/mex/

In Linux, you compile with
gcc -ansi -I<include dir> -o <result> <source> -L<libdir> -lmat -lmx

after you get the following libraries and include files
libmat.so, libmx.so, libmi.so, libut.so, mat.h, matrix.h

Mathworks justification for this is:
# Updating the Libraries
# 
# The API libraries are subject to change. However, it is not necessary
# for you to recompile your MAT-file applications each time the libraries
# change. If you update the shared libraries on your system by copying down
# the latest versions from The MathWorks FTP site and replacing the old ones
# with the new ones, your MAT-file applications will use the new version.

Anyone who wants to do this should find out the exact licencing
of the libs from Mathworks. I remember it being free but I might
be wrong. 

So, it seems to be possible to freely (ie free beer) distribute
programs that can read matlab 5.? files, but, since the source
is explicitly not available this functionality can't be
GPLed.

It may be possible to distribute *.oct files which hook to these
libraries with a README file about how to get them. But I seriously
doubt that jwe would be in favour of this kind of kludge.


______________________________________________________________
Andy Adler,                               address@hidden




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