Re: 1D PDE solver for Octave

[Bill Greene]

>This version of the Makefile should be relatively platform independent
>as it relies on the "mkoctfile".

Yes, I see the value of that.

Nevertheless, I had to make quite a few changes to your Makefile in order

to build on debian linux. The pre-built packages for the various dependencies

that I installed with something like

apt-get install xyz

put the contents in very different places than on your OSX system. The Makefile

has to change quite a bit if a package is installed in /opt vs being scattered

through /usr/local. On Windows, I don't think packages for the dependencies

even exist.

Regarding demo, I removed the non-working demo section from pde1d.m,

created an "examples" directory, and put a single file "heatCond.m" in

there.

On Tue, Jul 5, 2016 at 1:08 PM, Carlo De Falco <address@hidden> wrote:

Bill,

On 5 Jul 2016, at 18:31, Bill Greene <address@hidden> wrote:

> Glad to hear you were able to build on OSX. I don't currently have access to that platform.

This version of the Makefile should be relatively platform independent
as it relies on the "mkoctfile".

This is the standard approach used in all Octave packages.
Using a slightly improved version of this file you should
be able to quite easily reorganize your code into a package
using thie procedure described here:

https://www.gnu.org/software/octave/doc/interpreter/Creating-Packages.html#Creating-Packages

this is how Octave extesions are

> Regarding the demo, it looks to me like the first "demo" line is
> %!demo
> I don't see an extra space.

there shoudn't be any, the first line must be exactly

%!demo

the space should be in the other lines, as described here:

https://www.gnu.org/software/octave/doc/interpreter/Demonstration-Functions.html#Demonstration-Functions


> I haven't yet tried on linux but when I do
> demo pde1d
> on windows, I get this error:
> error: element number 1 undefined in return list
> error: called from
>     demo at line 111 column 13
>
> >Even if I fix this the demo does nothing useful, it defines a
> >bunch of functions but doesn't run anything.
>
> OK, I just took the contents of one of my test m-files and put
> a %! in front of every line. So maybe there should be
> %!heatCond
> as the last line in the demo section to call the "main" function?

typing "demo pde1d" is equivalent to copying the contents of the demo
blocks and typing "enter". If you do that, do you get any interesting result?

In the manual page for demo linked above, please read carefully the paragraph about
defining functions in a demo block:

'... Finally, because demo evaluates within a function context it is not possible to define new functions within the code. Anonymous functions make a good substitute in most instances. If function blocks must be used then the code eval (example ("function", n)) will allow Octave to see them. This has its own problems, however, as eval only evaluates one line or statement at a time. In this case the function declaration must be wrapped with "if 1 <demo stuff> endif" where "if" is on the same line as "demo" ...'

c.