Okay, so I need to make some plots that neither MathCAD nor excel can do easily, so I bit the bullet and installed Octave. After wrestling with it for a couple of days I have to say I am, so far, extremely underwhelmed. I can't seem to find any succint help references. The online manual has a good bit of info, but it's not well organized IMHO, and not at all easy to wade through. In general, it's a bit lacking, IMHO, but I guess that goes with the price. So after being unable to sort through my difficulties any other way, I thought I'd try to ask here since I know there are some Octave users here. FWIW, I downloaded the latest version, which is 3.0.0, and the SciTE editor was bundled with it. I've a number of old Matlab programs, and have been, futilely, trying to make some progress with editing new programs. The common problem seems to be "undefined near line xx column 1". The file in which this is currently happening only has 33 lines, but it's reporting "undefined near line 50 column 1". Oddly if I issue a "clear all" and then immediately re-run the file, with no other changes, the line count increments. Like this: ex_prog error: 'ex_prog' undefined near line 50 column 1 clear all ex_prog error: 'ex_prog' undefined near line 51 column 1 clear all ex_prog error: 'ex_prog' undefined near line 52 column 1 Sometimes it complains about "undefined" near a line that has the little expand/contract +/- in the first column, although that doesn't seem to add a character to the actual file. It doesn't seem to matter whether the file has been recently opened or saved with another editor, it just finds these mysterious little reasons to never run a program. I did manage to plot a single cycle of a sine wave (and the plot was, again, underwhelming), but anything more complicated than that doesnt get anywhere. Is this a recognizable problem to anyone? Is there a better place to go for answers? I didn't find a relevant newsgroup (other than the matlab newsgroup, which I'd guess wouldn't necessarily be helpful), nor have I found any relevant forums. Eric Jacobsen Minister of Algorithms Abineau Communications http://www.ericjacobsen.org
Questions regarding Octave
Started by ●March 23, 2008
Reply by ●March 23, 20082008-03-23
Hi Eric, There is an octave newsgroup: comp.soft-sys.octave There is also an IRC channel on freenode.net called #octave. Regarding your error, would it be possible for you to post the code? I can't help too much just based on what you wrote. -- % Randy Yates % "The dreamer, the unwoken fool - %% Fuquay-Varina, NC % in dreams, no pain will kiss the brow..." %%% 919-577-9882 % %%%% <yates@ieee.org> % 'Eldorado Overture', *Eldorado*, ELO http://www.digitalsignallabs.com
Reply by ●March 23, 20082008-03-23
On Mar 23, 8:22 pm, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> Okay, so I need to make some plots that neither MathCAD nor excel can > do easily, so I bit the bullet and installed Octave. After wrestling > with it for a couple of days I have to say I am, so far, extremely > underwhelmed.yer not the only one, after all it seems intended to be a gnu freeware counterpart to MATLAB. i contacted Eaton (and got on the Octave developer's list for a little while) to propose they do to Octave what i have, for more than a decade, been trying to get MATLAB to do: generalize handling array indices so that an array can have non- positive integer indices; so that the indices of the upper-left corner need not always be (1,1). fell on deaf ears. r b-j
Reply by ●March 23, 20082008-03-23
On Mar 23, 8:22 pm, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> Okay, so I need to make some plots that neither MathCAD nor excel can > do easily, so I bit the bullet and installed Octave. After wrestling > with it for a couple of days I have to say I am, so far, extremely > underwhelmed.yer not the only one, after all it seems intended to be a gnu freeware counterpart to MATLAB. i contacted Eaton (and got on the Octave developer's list for a little while) to propose they do to Octave what i have, for more than a decade, been trying to get MATLAB to do: generalize handling array indices so that an array can have non- positive integer indices; so that the indices of the upper-left corner need not always be (1,1). fell on deaf ears. r b-j
Reply by ●March 23, 20082008-03-23
On Mar 23, 8:22 pm, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> Okay, so I need to make some plots that neither MathCAD nor excel can > do easily, so I bit the bullet and installed Octave. After wrestling > with it for a couple of days I have to say I am, so far, extremely > underwhelmed.yer not the only one, after all it seems intended to be a gnu freeware counterpart to MATLAB. i contacted Eaton (and got on the Octave developer's list for a little while) to propose they do to Octave what i have, for more than a decade, been trying to get MATLAB to do: generalize handling array indices so that an array can have non- positive integer indices; so that the indices of the upper-left corner need not always be (1,1). fell on deaf ears. r b-j
Reply by ●March 23, 20082008-03-23
On Mar 23, 8:22 pm, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> Okay, so I need to make some plots that neither MathCAD nor excel can > do easily, so I bit the bullet and installed Octave. After wrestling > with it for a couple of days I have to say I am, so far, extremely > underwhelmed.yer not the only one, after all it seems intended to be a gnu freeware counterpart to MATLAB. i contacted Eaton (and got on the Octave developer's list for a little while) to propose they do to Octave what i have, for more than a decade, been trying to get MATLAB to do: generalize handling array indices so that an array can have non- positive integer indices; so that the indices of the upper-left corner need not always be (1,1). fell on deaf ears. r b-j
Reply by ●March 24, 20082008-03-24
On Mar 23, 7:49 pm, robert bristow-johnson <r...@audioimagination.com> wrote:> ... > yer not the only one, after all it seems intended to be a gnu freeware > counterpart to MATLAB. i contacted Eaton (and got on the Octave > developer's list for a little while) to propose they do to Octave what > i have, for more than a decade, been trying to get MATLAB to do: > generalize handling array indices so that an array can have non- > positive integer indices; so that the indices of the upper-left corner > need not always be (1,1). > > fell on deaf ears. > > r b-jSo, doesn't that make Octave an accurate counterpart to MATLAB? But, in the spirit of GNU freeware, what did they say when you offered to implement the change for them? Dale B. Dalrymple http://dbdimages.com
Reply by ●March 24, 20082008-03-24
On Sun, 23 Mar 2008 22:29:23 -0400, Randy Yates <yates@ieee.org> wrote:>Hi Eric, > >There is an octave newsgroup: > > comp.soft-sys.octaveAh, thanks. Now the mystery is why the group search in Free Agent didn't find that...>There is also an IRC channel on freenode.net called #octave. > >Regarding your error, would it be possible for you to post the code? I >can't help too much just based on what you wrote.It seems to be code independent and somehow associated with the file. It appears to be complaining about some mysterious whitespace marker or something, and since in the one example it's complaining about a line well past the end of the file the code probably has nothing to do with it. Nevertheless, try this: _________________________________ % % 5/1/96 Eric Jacobsen % % Design a butterworth filter and determine the equivalent FIR taps. % order=4; % Order of filter. cutoff=0.25; % Cutoff relative to 1.0 = 1/2 sample rate. [B,A]=butter(order,cutoff); end; ___________________ That's an ancient file that I had laying around that's small and exhibits the problem. For this one it says error: 'buttgen' undefined near line 60 column 1 Well, the file only has 13 lines. Grrr. Eric Jacobsen Minister of Algorithms Abineau Communications http://www.ericjacobsen.org
Reply by ●March 24, 20082008-03-24
Eric,
If possible send the code to
bharat at arithos dot com.
I will have a look and suggest what might go wrong.
The newer versions of octave does not have the
plot zoom capability and hence u might have some
trouble zooming into plots.
1. Install octave 2.1.73 version. This is most
stable and I have been using it for past
6 months without any issues (some very minor
issues which can easily be resolved).
2. If you are installing on linux machine then in
your home directory you should edit one file
called .gnuplot and in that file put
set mouse
close, save the file and then invoke octave. This
will help zooming on the figure/plot using 3rd mouse
button. Press 3rd mouse button and drag.
Just remember one thing: You can zoom only the
last active plot. So whichever plot you want
to zoom on, it should be put on the end of the
code.
3. On windows machine, install the cygwin version, it
works fine and allows you to zoom plot. I am using
this on windows vista and version of octave is
again 2.1.73. After installation
a. double clik on cygwin icon.
b. startx
c. In X window type octave.
4. Octave has figure stickiness phenomena, to get over
always do:
figure; clf; hold on;
plot(x, 'r');
plot(y, 'g');
hold off;
for the next new plot do again
figure; clf; hold on;
plot(a, 'k');
plot(b, 'c');
hold off;
5. For the active figure/plot some useful short keys
a : zoom to original full view
g : grid on/off (toggle button)
l : y-axis log scale toggle button
r : ruler
h : help on plot commands
Hope this benefits other octave users too. Just a
side note. I have provided DSP training to Karmic
Engineers (13 of them) full day courses for 15 days.
The whole training was done using Octave 2.1.73.
Only few minor hiccups were there but they can
easily be resolved. GOD bless John Eaton's Team
and all the guys who contributed to Octave.
No doubt the golden age of free software has arrived.
Thanks and Regards
Bharat Pathak
Arithos Designs
www.Arithos.com
........DSP Design Consultancy and Training Company........
Reply by ●March 24, 20082008-03-24
>order=4; % Order of filter. >cutoff=0.25; % Cutoff relative to 1.0 = 1/2 sample rate. > >[B,A]=butter(order,cutoff); > >end;Eric, This file runs fine for me. Only thing that I did is to remove extra "end;" command at the end of the file. The output generated is B = 0.010209 0.040838 0.061257 0.040838 0.010209 A = 1.00000 -1.96843 1.73586 -0.72447 0.12039 I think the problem for you might be something like this, you have your own version of a file called "butter.m" you could loacate it using which butter In that file you are calling one more function called "buttgen" and this could be problem. Also make sure that your filenames do not collide with standard function names provided by octave. Thanks and Regards Bharat Pathak www.Arithos.com DSP Design consultancy and training company
