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As some of you might know, my other pet project besides Octave, is BioSig http://biosig.sf.net. BioSig is designed in such a way that it can be used with both, Matlab and Octave. Mostly for performance reason, we cannot abandon support for Matlab [1,2]. Octave is a viable alternative in case the computational performance is not important. In order to decide on the future strategy of BioSig, I hope to get answers on the following questions: 1) Core development of Octave: At the meeting of Octave developer in 2006, the issue was raised that the Octave is about 4 to 5 times slower than Matlab [1]. (I repeated the tests just recently, the results are attached below, and show a difference of factors up to 13, average ~5) This issue is most relevant for large computational jobs, were it makes a difference whether a specific task takes 1 day or 5 days. Is anyone working to address this problem? Is there any hope that the performance penalty becomes smaller or will go away within a reasonable amount of time ? 2) Coding style: Octave understands a superset of commands compared to matlab, and it seems the current policy is to enforce the "octave style" and make the use of toolboxes incompatible for a use with Matlab. Is not it sensible to write platform-neutral applications ? Specifically, is not it in our own interest (wider usage make the code more robust) that matlab users are not "forced" to buy additional toolboxes but can use open source toolboxes e.g. from octave-forge? 3) Scope of Octave and Octave-Forge: Open source software has its own merit, but sometimes also other factors (e.g. additional costs in hardware, energy supply and cooling systems, energy efficiency = "green computing") need to be considered. Given the fact that octave-core is currently slower for some tasks, it is worth considering to use proprietary mat-engine. The question is whether Octave and Octave-forge should provide support of toolboxes for matlab users too, or whether these users should go somewhere else? What do you think ? Alois [1] http://arxiv.org/abs/cs/0603001v1 [2] benchmark from biosig (bench_biosig.m) http://biosig.cvs.sourceforge.net/viewvc/biosig/biosig/demo/bench_biosig.m?revision=1.7&view=markup In order to repeat the benchmark, you need biosig for octave and matlab, the tsa-toolbox and the nan-toolbox from octave-forge. The results are obtained from an AMD64 quad core machine with 64bit Ubuntu 8.10. Version: 3.1.54+ cputime toc[s] task ================================ 2.244 2.853 sload l1.gdf(#1) 77.105 78.547 wackermann 1.988 1.993 barlow 2.128 2.133 hjorth 0.992 0.994 TDP 200.065 200.119 aar #1 195.428 195.439 aar #2 197.860 197.862 aar #3 65.684 519.944(#2) findclassifier barlow LD3 66.336 66.333 findclassifier hjorth LD3 66.240 66.251 findclassifier aar LD3 65.748 65.753 findclassifier Wackermann LD3 65.760 65.759 findclassifier TDP LD3 - ----------------------------------- 1007.58 1463.98(#2) total Version: 7.6.0.324 (R2008a) cputime toc[s] task ================================ 0.150 0.148 sload l1.gdf(#1) 1.110 1.096 bandpower 12.800 12.688 wackermann 1.550 1.471 barlow 1.600 1.477 hjorth 1.290 1.053 TDP 40.370 40.334 aar #1 39.810 39.782 aar #2 40.040 39.823 aar #3 7.020 4.979 findclassifier bp LD3 7.440 5.010 findclassifier barlow LD3 7.550 5.093 findclassifier hjorth LD3 7.930 5.205 findclassifier aar LD3 7.860 5.230 findclassifier Wackermann LD3 6.600 4.844 findclassifier TDP LD3 - ------------------------------ 196.400 179.984 total Remarks (#1) The differences in "sload l1.gdf" are mostly to the fact that a mex-version was used in Matlab, while Octave uses an m-script. (#2) waiting for some key pressing. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAknt8FYACgkQzSlbmAlvEIi+YgCgopPkViJplWhYcTVS1gVRGTFc kEoAnjfXUqOGcVZ7pz5f91gA4MSKSccX =kcr2 -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. http://p.sf.net/sfu/p _______________________________________________ Octave-dev mailing list Octave-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/octave-dev
