Normalize a collection of arrays on a specific column

*To*: mathgroup at smc.vnet.net*Subject*: [mg85897] Normalize a collection of arrays on a specific column*From*: Curtis Osterhoudt <cfo at lanl.gov>*Date*: Wed, 27 Feb 2008 04:24:07 -0500 (EST)*Organization*: LANL*Reply-to*: cfo at lanl.gov

(Note: this is a re-send of a message. I haven't seen the message show up in the list (or its archives), so I'm assuming it's lost in the aether. I apologize if this shows up twice.) Hi, all, I'm looking for a relatively efficient (read: not doing so element-by-element) way of taking a collection of several matrices, all of the same m x n dimensions (say), and normalizing all of them in whatever column I choose. If possible, it would be nice to extend this to any number of dimensions, but that's not necessary now. For example, I'm looking for a function, "normalizeColumn[listOfLists_, p_]" which would normalize the pth column of all of the lists, not individually, but over the whole set, returning the whole set with just the pth column changed in each of its constituent lists. Let dat1 = {{1,3,4}, {2,2,-5}, {1,1,1}} and dat2 = {{0, 3, 6}, {2,1,4}, {5, 3, -5}}. Then if dat3 = {dat1, dat2}, the normalizeColumn function should return normalizeColumn[dat3, 2] = {{{1, 1, 4}, {2, 1/2, -5}, {1, 0, 1}}, {{0, 1, 6}, {2, 0, 4}, {5, 1, -5}}}. I'm quite certain there's an easy way to do it; I should be able to do something analogous on several hundred, 200 x 200 matrices at the same time. Best wishes, and thanks, Curtis O. -- ========================================================== Curtis Osterhoudt cfo at remove_this.lanl.and_this.gov PGP Key ID: 0x4DCA2A10 Please avoid sending me Word or PowerPoint attachments See http://www.gnu.org/philosophy/no-word-attachments.html ==========================================================

**Follow-Ups**:**Re: Normalize a collection of arrays on a specific column***From:*Carl Woll <carlw@wolfram.com>