From octave-graphics-request at bevo dot che dot wisc dot edu Tue Jun 24 01:29:08 2003 Subject: Gnuplot From: Daniel J Sebald To: octave-graphics at bevo dot che dot wisc dot edu Cc: octave-maintainers at bevo dot che dot wisc dot edu Date: Tue, 24 Jun 2003 01:40:19 -0500 Dear Octave graphics developers and maintainers, There has been some discussion on the Gnuplot developer list about image support and binary data input. We are curious if Octave developers have interest in the discussion and/or in giving feedback on Gnuplot/Matlab interaction. (I seem to recall binary data being on your wish list.) I'll briefly explain how this has come about and which Octave mailing list I should direct any further comments to. I briefly looked through the graphics mailing list and see that Eric Chassande-Mottin contributed a script which uses Gnuplot's pm3d features to plot images with the common annotation for axes, etc. This is essentially the motivation for incorporating an image routine into Gnuplot. (The main difference between pm3d and the image routine is that pm3d plots in rectangles while the image routine attempts to use the underlying driver imaging functions.) The image routine is currently a patch but is robust and works nicely with Octave's image scripts. There is still some syntax to be decided on. The issue is that images have a lot of data and to make viewing them reasonably fast requires a binary data mode, as opposed to saving images in ASCII format in a file. This was done in a hack fashion in Gnuplot just as a "proof of concept". An image from Octave is written in binary format to a file via the fwrite() command, then Gnuplot can read the binary data file. So, the discussion on the Gnuplot list right now is about how best to implement binary data in terms of syntax, etc. anticipating how various applications might use the feature. I have a string of emails on the discussion if someone is interested and I welcome anyone to join the Gnuplot discussion list for a while: http://lists.sourceforge.net/lists/listinfo/gnuplot-beta Regards, Dan Sebald