Replacing Parts of a List

*To*: mathgroup at smc.vnet.net*Subject*: [mg28742] Replacing Parts of a List*From*: Roger Jones <rmj at SLAC.Stanford.EDU>*Date*: Fri, 11 May 2001 03:38:58 -0400 (EDT)*Organization*: Stanford Linear Accelerator Center*Sender*: owner-wri-mathgroup at wolfram.com

Given x={1,2} then setting part 1 to 10 (say) is done via x[[1]]=10. This appealing as it is a condensed notation and is I believe, very efficient for large arrays. However, with a subscripted symbol (such as Subscript[x,y]) how is it done? It can be achieved with Subscript[x,y]=ReplacePart[Subscript[x,y],10,1] but this is a little unwieldy. Is there some method (using Hold[Subscript[x,y]] or something like this) that allows a direct replacement? Thank you! -Roger Jones