Re: Compress timing with different data types
- To: mathgroup at smc.vnet.net
- Subject: [mg97735] Re: Compress timing with different data types
- From: mark mcclure <mcmcclur at unca.edu>
- Date: Fri, 20 Mar 2009 02:38:53 -0500 (EST)
- References: <gpsr4o$mh9$1@smc.vnet.net>
On Mar 19, 3:10 am, Yves Klett <yves.kl... at googlemail.com> wrote: > I noticed that the speed of Compress is very much dependent on > the type of data that is compressed: > ... > compressing an expression only containing lists and numbers is about > 60 times faster than compressing an expression containing Line > statements. And the difference gets worse the larger the expression > becomes... > > Does anyone have experience and/or a workaround with that > behaviour (6.03 & 7.01 on WinXP)? Running your code in both V6.0.3 and V7.0.1 on my Mac laptop, I get speed ratios of more like 6 or 7, rather than 60. Of course, I wouldn't expect Compress to accomplish anything with an array of random numbers, while an expression containing many copies of a Line primitve would be compressed a lot. Perhaps this has something to do with it. Incidentally, there's no reason to map Line onto data. That is Line[data] is perfectly valid and renders faster than Line /@ data. Mark McClure