Re: odd behaviour in rule delayed

*To*: mathgroup at smc.vnet.net*Subject*: [mg21506] Re: odd behaviour in rule delayed*From*: "Allan Hayes" <hay at haystack.demon.co.uk>*Date*: Fri, 14 Jan 2000 02:43:26 -0500 (EST)*References*: <851dn1$43k@smc.vnet.net> <200001070520.AAA08503@smc.vnet.net> <85i124$1qh@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Francisco: Your example (edited) list = {1, 0, 1, 0, 0, 1} {1, 0, 1, 0, 0, 1} k = 0; {1, 0, 1, 0, 0, 1} /.1 :> ++k {10., 0, 10., 0, 0, 10.} :> ++k This is because {1, 0, 1, 0, 0, 1} /.1 :> ++k is parsed as ({1, 0, 1, 0, 0, 1} /(.1)) :> ++k So / gives division by 0.1. Solutions: add space between /. and 1 k = 0; {1, 0, 1, 0, 0, 1} /. 1 :> ++k {1, 0, 2, 0, 0, 3} Or, clearer, k = 0; {1, 0, 1, 0, 0, 1} /. (1 :> ++k) {1, 0, 2, 0, 0, 3} k = 0; {1, 0, 1, 0, 0, 1} /. {1 :> ++k} {1, 0, 2, 0, 0, 3} Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 "Francisco Gutierrez" <rpena at impsat.net.co> wrote in message news:85i124$1qh at smc.vnet.net... > I have M 4.0, window 95. > I have a list of 0's and 1's, and I want the one's to perform a consecutive > numeration. For example, transform {1,0,1,0,0,1} into {1,0,2,0,0,3}. > > The easiest (and most elegant, I think) way to do it is with a counter and > rule delayed: > list={1,0,1,0,0,1} > kk=0; newlist={1,0,1,0,0,1} /.1:>++k > > However, the answer I get from this operation is completely > odd:{10.,0,10.,0,0,10.}:>++k. I closed my session and re-started my > computer, but I keep getting the same stuff. I don't understand what is > happening. By the way, this problem didn't appear in M3.0. > > Can somebody help me? > > Francisco Gutierrez > >

**References**:**Re: Using Mathematica to Create Technical Documents***From:*"Tony Duffy" <tduffy@uswest.net>