kmatplot-general

[Kmatplot-general] Documentation

[<jos...@gm...>]

Hi,
	I have installed kmatplot (finally!) using the debian package. In the 
past, it was impossible for me to compile the source, so I am a happy 
person. However, I can't find any documentation on how to do a number 
of things.

	What I want to do is quite simply load up a file (a NxM matrix), and 
plot it as an image (X and Y axis are not obligatory), maybe with a 
colorbar (à la Matlab :D) on the side. In other words, namely matlab 
words :-):
imagesc(<data_set>)
colorbar

	I can somewhat get the data, but I can't for my life decide which 
option I need to use to get the graph plotted. I would have guessed 
that importing a dataset (this is achieved easily following one of the 
examples), adding some graphs and using the Wizard would do it, but I 
am at a loss, as I get a lot of axes, and I don't know what to do with 
them :( Is there some documentation, or step-by-step example for idiots 
like myself?

	Many thanks
José
 
-- 
José L Gómez Dans			PhD student
Tel: +44 114 222 5582			Radar & Communications Group
FAX; +44 870 132 2990			Department of Electronic Engineering
					University of Sheffield UK

[Kmatplot-general] Documentation

[Kristy M. <kr...@no...>]

Hi all, 

I'm VERY new to KMatPlot and I can't seem to find any documentation for the 
stand-alone KMatPlot program.  I've found documentation for the API and a "docs" 
folder in the KMatPlot stuff, but it was basically empty.

Does anyone know where I can get documentation?

Thank you,
Kristy

Re: [Kmatplot-general] Documentation

[Hugo v. d. M. <s13...@ba...>]

> 	I have installed kmatplot (finally!) using the debian package. In the 
> past, it was impossible for me to compile the source, so I am a happy 
> person. However, I can't find any documentation on how to do a number 
> of things.
<SNIP>
> them :( Is there some documentation, or step-by-step example for idiots 
> like myself?

There are samples in the Help menu, however these do not work "out of
the box" with the current Debian package. I have not yet figured out how
to tell kmatplot that everything is installed in /usr/ and not
/usr/local/. Go to Settings->"Configure KMatplot" and change the Install
Path to /usr (instead of /usr/local). Then the samples in the help menu
will work.

That has some step-by-step instructions that shows you around a bit. Not
exactly what you are looking for, I'm sure, but maybe it will help to
get a better idea of how the whole app works.

I cannot help you much more than that, I haven't had time to play much
with it either. (I am also more interested in operating the thing from
Octave, which I am also not very sure about - don't know how to draw
nice 3D graphs yet.)

Hope this helps,
Hugo van der Merwe

Re: [Kmatplot-general] Documentation

[Laurent J. <lja...@fy...>]

On Thursday 16 May 2002 14:10, Jos=E9 Luis G=F3mez Dans wrote:
> Hi,
> 	I have installed kmatplot (finally!) using the debian package. In the
> past, it was impossible for me to compile the source, so I am a happy
> person. However, I can't find any documentation on how to do a number
> of things.
>
> 	What I want to do is quite simply load up a file (a NxM matrix), and
> plot it as an image (X and Y axis are not obligatory), maybe with a
> colorbar (=E0 la Matlab :D) on the side. In other words, namely matlab
> words :-):
> imagesc(<data_set>)
> colorbar

Here is a simple example (I hope it helps you)

octave:26> [x,y]=3Dmeshgrid(1:256);
octave:27> g=3Dexp(-((x-128).^2+(y-128).^2)/1000);
octave:28> kaddaxes(0)
ans =3D 5
octave:29> kimage(g)
ans =3D 0

For the colorbar, I don't know.
Perhaps directly on kmatplot.


Bye,
Laurent.

Re: [Kmatplot-general] Documentation

[Laurent J. <lja...@fy...>]

On Thursday 16 May 2002 17:53, Laurent Jacques wrote:
>
> Here is a simple example (I hope it helps you)
>
> octave:26> [x,y]=meshgrid(1:256);
> octave:27> g=exp(-((x-128).^2+(y-128).^2)/1000);
> octave:28> kaddaxes(0)
> ans = 5
> octave:29> kimage(g)
> ans = 0
>
> For the colorbar, I don't know.
> Perhaps directly on kmatplot.
>

Bug detected:

In the above example, it seems that kmesh of octave causes a segfault of 
kmatplot. I haven't produced it on a i386 but on an alpha (debian woody 
sidded, octave2.1) so I don't know if this bug is also present on i386 ?

Bye
Laurent.

Re: [Kmatplot-general] Documentation

[Hugo v. d. M. <s13...@ba...>]

> > Here is a simple example (I hope it helps you)
> >
> > octave:26> [x,y]=meshgrid(1:256);
> > octave:27> g=exp(-((x-128).^2+(y-128).^2)/1000);
> > octave:28> kaddaxes(0)
> > ans = 5
> > octave:29> kimage(g)
> > ans = 0

Thanks, kimage is nice. kcontour is also. I'm happy with the 2D stuff.

> Bug detected:
> 
> In the above example, it seems that kmesh of octave causes a segfault of 
> kmatplot. I haven't produced it on a i386 but on an alpha (debian woody 
> sidded, octave2.1) so I don't know if this bug is also present on i386 ?

It's kmesh that I want to figure out. (One uses kaddaxes(1) to get 3D
axes instead of 2D.)

In my experience, kmatlot dies if one passes it e.g. kmesh(g), but is
happy if you pass it kmesh(x,y,g). I have to replace meshgrid(1:256)
with meshgrid(1:40) though, as anything larger causes the graph to not
be displayed. With it displayed, it's a set of vertical planes, not a
nice meshed surface...

Hugo

Re: [Kmatplot-general] Documentation

[Laurent J. <lja...@fy...>]

On Thursday 16 May 2002 20:32, Hugo van der Merwe wrote:
> It's kmesh that I want to figure out. (One uses kaddaxes(1) to get 3D
> axes instead of 2D.)

Of course, I forgot that point.

Instead of killing kmatplot, a bad use of kmesh after kaddaxes(0) instead of 
kaddaxes(1) would have to return an error message.

>
> In my experience, kmatlot dies if one passes it e.g. kmesh(g), but is
> happy if you pass it kmesh(x,y,g). I have to replace meshgrid(1:256)
> with meshgrid(1:40) though, as anything larger causes the graph to not
> be displayed. With it displayed, it's a set of vertical planes, not a
> nice meshed surface...

Strange limitation. It's a bit annoying.

Kamil, it's a detail but, is the kaddaxes procedure is absolutely necessary 
in Octave ? 
I think that a good use for a kmatplot "octaved" will be to approach the 
matlab way where you have no equivalent of kaddaxes.

Another point, do you it is possible to control the colormap through octave ?
I think about something like 
	kcolormap("colormap_string");
But perhaps it already exists and I didn't have read correctly the doc (RTFM)?

Thanks,
Laurent.

Re: [Kmatplot-general] Documentation

[Hugo v. d. M. <s13...@ba...>]

> > In my experience, kmatlot dies if one passes it e.g. kmesh(g), but is
> > happy if you pass it kmesh(x,y,g). I have to replace meshgrid(1:256)
> > with meshgrid(1:40) though, as anything larger causes the graph to not
> > be displayed. With it displayed, it's a set of vertical planes, not a
> > nice meshed surface...
> 
> Strange limitation. It's a bit annoying.

Is there a BTS somewhere for kmatplot, where one can also report
wishlist items, etc?

> Kamil, it's a detail but, is the kaddaxes procedure is absolutely necessary 
> in Octave ? 
> I think that a good use for a kmatplot "octaved" will be to approach the 
> matlab way where you have no equivalent of kaddaxes.

I think that while it is useful to be able to access different sets of
axes from octave, ideally it should also be more "directly compatible"
with what people already know. I would suggest that if a call is made to
kmesh or kplot etc. before a call to kaddaxes has been made, that axes
could be created automatically?

At a later version, if one wants more compatibility, one would want to
have a "hold" clone as well. It is always difficult to remain
"compatible" with existing solutions, while at the same time trying to
develop something new with more features. Hence maybe there needs to
(eventually) be "two modes" of operation, one compatible as far as
possible, the other - possibly turned on as soon as any of its features
are used - something that gives access to all the nice new features?

> Another point, do you it is possible to control the colormap through octave ?
> I think about something like 
> 	kcolormap("colormap_string");

Ideally, eventually, an octave would want to be able to e.g. generate
nice postscript output from kmatplot without ever touching his mouse, or
the kmatplot app for that matter: while one of kmatplot's design
features is its "interactiveness", an octave user would often want to
write a script that generates graph output. And if he changes something
in this script, he(/she) wants to regenerate all the output without
intervention...

> But perhaps it already exists and I didn't have read correctly the doc (RTFM)?

Is there a doc to read that I do not know about? On the topic of docs,
does octave have some nice docs (I'm sure it does...) on writing
extensions, e.g. the kmatplot octave functions? (Depending on how my
holiday looks - depending on what work I'm given at my holiday job - I'd
like to play with octave/kmatplot coding a bit.)

Thanks,
Hugo van der Merwe

[Kmatplot-general] kmatplot-dev ?

[Laurent J. <lja...@fy...>]

Hello Hugo,

Do you think to be able (when you have time of course) to create a 
development package for kmatplot ? 

I would be great to have a package kmatplot-dev which gathers
- headers of kmatplot;
- dynamic and static libraries;
- demos like demo2d.cpp and demo3d.cpp;
- ... anything interesting for development.

In particular, it allows us to create new functions for the octave interface 
when we want to compile new .oct file with mkoctfile.

What is your opinion ?

Bye,
Laurent.

	

Re: [Kmatplot-general] kmatplot-dev ?

[Hugo v. d. M. <s13...@ba...>]

> Do you think to be able (when you have time of course) to create a 
> development package for kmatplot ? 

Certainly. I will try my best to get round to it this weekend, or before
this weekend. (No guarantees though.)

> I would be great to have a package kmatplot-dev which gathers
> - headers of kmatplot;
> - dynamic and static libraries;
> - demos like demo2d.cpp and demo3d.cpp;
> - ... anything interesting for development.
> 
> In particular, it allows us to create new functions for the octave interface 
> when we want to compile new .oct file with mkoctfile.
> 
> What is your opinion ?

It's a great idea.

What bothers me most about the current package though is "qsettingsdir",
kmatplotrc, and not knowing where I should install that file, how to get
kmatplot to actually find it...

I am hoping Kamil might be able to help when he gets to read the mailing
list again, he apparently has some connection problems at the moment.

Hugo

Re: [Kmatplot-general] kmatplot-dev ?

[Laurent J. <lja...@fy...>]

On Wednesday 22 May 2002 00:08, you wrote:
> Hello Hugo,
>
> Do you think to be able (when you have time of course) to create a
> development package for kmatplot ?
>
> I would be great to have a package kmatplot-dev which gathers
> - headers of kmatplot;
> - dynamic and static libraries;
> - demos like demo2d.cpp and demo3d.cpp;
> - ... anything interesting for development.
>
> In particular, it allows us to create new functions for the octave
> interface when we want to compile new .oct file with mkoctfile.

To complete what I said, the important library for the development of an 
octave interface (but this is not the most important library for a kmatplot 
development package) is
	libkmatplot_interface.a
created into 
	kmatplot-0.4/kmatplot/interface/libkmatplot_interface.a

Bye,
Laurent.