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Re: SparseArray, DensityGraphics, ContourGraphics, and SurfaceGraphics

• To: mathgroup at smc.vnet.net
• Subject: [mg54619] Re: SparseArray, DensityGraphics, ContourGraphics, and SurfaceGraphics
• From: "Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de>
• Date: Thu, 24 Feb 2005 03:21:22 -0500 (EST)
• Organization: Uni Leipzig
• References: <cvc84d$qrb$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Hi,

what has a sparse matrix to do with a density graphics ?
ArrayPlot[] is only used to visualize the sparse matrix, but
all the memory saving of the sparse matrix are destroyed when you
expand every entry in the matrix (not only the non zero values) to a
3D Polygon[] with 4 corners in Plot3D[] ...
It seems a good design decision not to support this nonsens ...
Regards
  Jens

"Mark Fisher" <mark at markfisher.net> schrieb im Newsbeitrag 
news:cvc84d$qrb$1 at smc.vnet.net...
> DensityGraphics works fine with SparseArray objects, but niether
> ContourGraphics nor SurfaceGraphics does. (I'm using 5.1 for Windows.)
> This seems to me like a poor design decision (if it's not a bug).
>
> sa=SparseArray[IdentityMatrix[10]];
> glist=Through[{DensityGraphics,ContourGraphics,SurfaceGraphics}[sa]];
> Show /@ glist;
>
> --Mark.
> 

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  • Re: Re: SparseArray, DensityGraphics, ContourGraphics, and SurfaceGraphics
    • From: DrBob <drbob@bigfoot.com>