Re: Gnuplot and Octave.

[Daniel J S. <dan...@ie...>]

Ethan Merritt wrote:

>On Friday 20 February 2004 02:54 pm, Hans-Bernhard Broeker wrote:
>  
>
>>Not after the fact.  gnuplot does not generally keep plotted data in
>>memory after the plot has been drawn, so it can't report them back to
>>octave, either.  This kind of data copying would have to be done at the
>>octave end of the connection instead.  There's, again, an exception to
>>this, but it only applies to mouse-enabled versions, and then only to 3D
>>plots, IIRC.
>>    
>>
>
>Only 2D I think you mean?  The x11 mousing code stores the axis
>info so that it can translate mouse clicks into plot coordinates.
>But it only does such translation for 2D plots.
>
>The outboard x11 driver, gplt_x11, stores most of the plot information
>implicitly. It needs this anyway in order to continuously display plots,
>even old plots, on the screen. There is a code stub in
>gplt_x11.c just waiting to pass mousing events from prior windows
>back to external applications. But as of now it is commented out
>because we have no such interface defined.
>
>If some interested parties on both the gnuplot and octave side work
>to define such an interface, I believe it would not be a tremendous
>amount of work to export data on demand from gnuplot_x11 to an
>octave session.
>

One small drawback though is that when the data reaches the point of 
gnuplot_x11 it has been translated to a new coordinate system.  I 
suppose the translation can be reversed, but there will be some 
precision discrepancies.

Dan