Sign Declaration

*To*: mathgroup at smc.vnet.net*Subject*: [mg80028] Sign Declaration*From*: Mr Ajit Sen <senra99 at yahoo.co.uk>*Date*: Sat, 11 Aug 2007 02:02:21 -0400 (EDT)

Dear MathGroup, Given the list A= {a,b,c,d,e,f,g,h}, I'd like to tell Mathematica (5.2) that a,b,...,e are +ve, and f,g,h are -ve. I'm using the following Table[Sign[A[[i]]]^=1,{i,5}]; Table[Sign[A[[i]]]^=-1,{i,6,8}]; My queries are : 1. Is it possible to combine the above into 1 Table[]? 2. How do I achieve the same thing with the construct x/:Sign[x]=1 in Table ? 3. Any more efficient ways of doing those sign declarations? Thanking you in advance. Ajit. ___________________________________________________________ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/

**Follow-Ups**:**Re: Sign Declaration***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>