Re: Q: Low hanging fruit?

[Jaroslav Hajek]

On Tue, Mar 11, 2008 at 9:48 AM, David Bateman
<address@hidden> wrote:
>
> Ben Abbott wrote:
>  >
>  > On Mar 10, 2008, at 9:47 PM, Bill Denney wrote:
>  >
>  >> Attached are three new functions.  Essentially now I'm just going
>  >> through the list of functions in matlab that are missing in octave
>  >> and writing the low hanging fruit.
>  >>
>  >> Have a good day,
>  >>
>  >> Bill
>  >
>  > Bill,
>  >
>  > Any chance you (or anyone else) have compiled a list of "low hanging
>  > fruit"?
>  >
>  > I expect there are a few individuals who would like to contribute to
>  > that effort.
>  >
>  > Personally, I'd be interested in writing some m-files during my spare
>  > time.
>  >
>  > Ben
>  >
>  No, but I have a list of all of the functions in Matlab 2007b core and
>  the split between those that are implemented in Octave and those that
>  aren't.. Makes it easy to find the low hanging fruit.. the
>  dlmread/dlmwrite, etc functions should be ported from octave-forge and
>  are already in a very good state in octave-forge itself. There are also
>  a fair few other functions that might be ported from octave-forge and so
>  those are the things I'd do first as the code already exists and its
>  just a matter of coding style, texinfo help and checking for matlab
>  compatibility.
>

I've already started working on dlmread/dlmwrite. The thing is that
octave-forge's
dlmread is not quite like Matlab's - it cannot handle the range
specification in spreadsheet format (like "A1..B10") and it cannot
read the complex numbers in Matlab format
<number>+<number>i. The Matlab version also appears to guess the separator from
the first nonblank line, while the octave-forge version just defaults
to tab or space.

Moreover, I'd like dlmread to start with Matrix and allocate a
ComplexMatrix only if it
actually encounters a complex number (real numbers are much more
common IMHO, that's why I suppose this optimization is worth it).

I had my PhD exams last Friday, so I haven't done much work, but if
it's a priority, I can try to finish it as fast as possible.

I have not yet looked at dlmwrite - but that should be easier to deal
with, especially if it
can stay in m-file form. Perhaps it can even be included straight away.
However, it's IMHO necessary to ensure that dlmwrite'd files can
always be dlmread'ed, ideally from both Octave and Matlab.

cheers,

-- 
RNDr. Jaroslav Hajek
computing expert
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz