Re: adding lists term by term

*To*: mathgroup at smc.vnet.net*Subject*: [mg113651] Re: adding lists term by term*From*: David Bailey <dave at removedbailey.co.uk>*Date*: Sat, 6 Nov 2010 04:59:32 -0500 (EST)*References*: <ib0lcs$gls$1@smc.vnet.net>

On 05/11/10 10:13, Trevor Rabey wrote: > When I type this: > > {-(1/2),1}+{17/13,17/52} > > I get: > > Syntax::sntxf: "{-(1/2),1}+" cannot be followed by "{17/13,17/52}". > > Syntax::sntxi: Incomplete expression; more input is needed. > > But if I copy the example from the Mathematica help: > > {a,b}+{c,d} > > and replace the a,b,c,d with my numbers, it works and gives me an array > added element by element. > Driving me crazy. What gives? > Pasting this expression into Mathematica, it works just fine. Just occasionally, Mathematica seems to end up with an expression containing some invisible text or peculiar box structure that makes seemingly valid syntax fail. My solution to this problem, is either to type the code in again, or to cut/paste it to a text editor and back again into a fresh cell. David Bailey http://www.dbaileyconsultancy.co.uk