Re: using interp1.m from Matlab in Octave?

[David Bateman]

Tom Holroyd wrote:
>>> Please don't use mathwork copyright material in Octave, and if 
>>> you do certainly don't say so on a public mailing list (unless 
>>> you like "cease and desist" letters for angry Mathwork's 
>>> lawyers).
> 
> Oh please, this is ridiculous. You can type whatever you want 
> into Octave. Poems from a (copyrighted) book of poetry, 
> mathematical formulas from anywhere ... Even, (gasp) .m files 
> that you paid for.

Tom,

Copyright material is subject to "fair-use". Also you have a contract
(maybe only a click-through for what that's worth) with mathworks in
addition to any coverage that copyright gives. If you use interp1.m from
Matlab in Octave, I see three cases

1) You don't have a copy of Matlab. Here you are clearly in breach of
copyright
2) You have an installed and paid for copy of matlab. Here is a grey
area in that can you have two instances of interp1.m at the same time
running. If so you are probably in breach of copyright
3) You have a paid for copy of matlab but uninstalled. From a copyright
point of view it should be ok to use interp1.m in Octave.

However, now what does the matlab contract states in 4.2

4. LICENSE RESTRICTIONS.  The License is subject to the express
   restrictions set forth below. Licensee shall not, and shall not
   permit any Third Party to:
<snip>
   4.2. adapt, translate, copy, or convert all or any part of a Program
        in order to create software, a principal purpose of which is to
        perform the same or similar functions as Programs licensed by
        MathWorks or to replace any component of the Programs;

Using interp1.m in Octave seems to falling clearly into that clause, as
Octave certainly performs the same function as Matlab and taking
interp1.m and using it in Octave is certainly "adapt, translate, copy".

So the contract does prevent this type of use, particularly if you are a
large installation site for Matlab and it might be reasonably expected
that Matlab had a contract physically signed with your institute. Click
through licensee however, given the dubious status of click through
licenses, are less sure. However, do you want to base your use of
interp1.m in Octave on the chance that click through licenses are invalid..

D.