Re: Saving Large Matrices
- To: mathgroup at smc.vnet.net
- Subject: [mg24801] Re: Saving Large Matrices
- From: "P.J. Hinton" <paulh at wolfram.com>
- Date: Sun, 13 Aug 2000 03:16:40 -0400 (EDT)
- Organization: Wolfram Research, Inc.
- References: <firstname.lastname@example.org>
- Sender: owner-wri-mathgroup at wolfram.com
On 10 Aug 2000 bbongiorno at attglobal.net wrote: > I need a effective way to store and retrieve a 300,000 x 44 matrix that > includes alpha numeric and numeric cells. > > The data is first downloaded from a database into a mathematica variable > in a note book. Included in some of the alpha numeric cells are commas, > tabs and spaces and therefore I cannot use Write function. If I use the > Write function to store the matrix, the integrity of the shape of the > matrix is impaired. > > The Export function works but it takes 24 hours to store the matrix on > a Pentium II 300 with major virtual memory usage. You don't say whether or not you need to make this data file available to other applications. If your are just trying to store it in a format that will be readable by the kernel, you may want to consider using the DumpSave function. This stores the expression in a binary format that can be read very quickly back into the kernel. -- P.J. Hinton User Interface Programmer paulh at wolfram.com Wolfram Research, Inc. Disclaimer: Opinions expressed herein are those of the author alone.