Re: Octave does not start gnuplot

[Ben Abbott]

On Nov 25, 2010, at 9:56 AM, Paul Schanda wrote:

> Hi Ben,
> 
> Sorry, I did not understand you properly in the beginning. I tried the 
> command within octave, which is probably what you meant. The result is: 
> empty. Neither X11 nor aqua
> 
> octave:1> getenv ("GNUPLOT")
> ans = 
> 
> Thus, I tried to set it to aqua. Nonetheless, plotting does not work:
> 
> octave:4> setenv ("GNUPLOT","aqua")
> octave:5> getenv ("GNUPLOT")
> ans = aqua
> octave:6> a=[1 2 3]
> a =
> 
>   1   2   3
> 
> octave:7> plot(a)
> octave:8> 
> 
> Again, no gnuplot opens....
> 
> Paul
> 
> Am 25.11.2010 um 15:29 schrieb Ben Abbott:
> 
>> 
>> On Nov 25, 2010, at 4:09 AM, Paul Schanda wrote:
>> 
>>> Hi there,
>>> 
>>> I have installed Octave and Gnuplot, using MacPorts, on my MacBook Pro. 
>>> The octave is version 3.2.4, gnuplot is Version 4.4 patch level 2. 
>>> Gnuplot's terminal type is set to 'aqua'.
>>> 
>>> I can start octave without problems and its functions seem to work. 
>>> However, when I try to plot something gnuplot is not started correctly. 
>>> I try the following:
>>> 
>>> octave:1> a=[1 2 3]
>>> octave:2> plot(a)
>>> 
>>> 
>>> These commands start up X11 as well as AquaTerm. 
>>> However, then nothing else happens. 
>>> octave goes back to a promt again:
>>> 
>>> octave:3> 
>>> 
>>> No gnuplot window pops up, no graph coming... There are no error messages,
>>> making it hard to know where to start.
>>> 
>>> I found that I have "gnuplot" in a couple of places, 
>>> because it apparently came
>>> with some other Unix-type programs I am using (such as NMRPipe). 
>>> I am not sure whether this can make problems.
>>> I have also tried to create an alias in my .cshrc, 
>>> such that I am sure that a command "gnuplot" points to the version 
>>> that I have installted together with octave.
>>> 
>>> Any ideas ?
>>> 
>>> By the way, I also find that I cannot cleanly exit octave. 
>>> It just gets stuck
>>> and I have to quit the program with Ctrl-C. 
>>> Could this be related ?
>>> 
>>> Thanks
>>> 
>>> Paul
>> 
>> What does the following return?
>> 
>>      getenv ("GNUTERM")
>> 
>> A proper result would be "x11" or "aqua".
>> 
>> Ben

To see which gnuplot Octave is trying to use, type ... 

        [status, output] = system (sprintf ("which %s", gnuplot_binary))
        status = 0
        output = /sw/bin/gnuplot

>From a terminal (a bash shell for example) try running the same gnuplot. If 
>gnuplot runs, then try a plot ...

        set term aqua
        plot sin(x)

I expect that you'll see a problem / error?

As you have other gnuplot's installed, I recommend you try each of them to 
determine which ones do, and don't, function correctly.

You can instruct Octave to use any of the gnuplot's by using Octave's 
"gnuplot_binary" function. For example, if you have a working install in 
/usr/bin then ...

        gnuplot_binary ("/usr/bin/gnuplot")

One final comment, as managing unix programs can be difficult, I recommend you 
take a look at macports or fink. They each simiplify unix program management.

Ben