Indexed element treated as number?
- To: mathgroup at smc.vnet.net
- Subject: [mg80055] Indexed element treated as number?
- From: "Jung-Tsung Shen" <jushen at gmail.com>
- Date: Sat, 11 Aug 2007 02:16:22 -0400 (EDT)
(* The following problem and alike have been asked before. I have
searched extensively the archive of this forum but couldn't find a
perfect solution. *)
To get an array of length n, where n is large and post-given, one
issues the command, for example,
n=100;
kList1=Array[a, n];
but it seems that there are some limitations to this approach. For
example, in cases that I know all of the elements are real, and would
like to issue, say,
a[37]/:Im[a[37]]=0;
I get an error message saying
"TagSet::sym: Argument a[37] at position 1 is expected to be a
symbol." To declare the element to be explicitly zero sometimes speed
up the computation.
For a list such as
kList2={k1, k2, k3, ..., k100};
there's no such limitations, but since the number of elements is
large, and is post-given, I couldn't have this before hand.
Is there any solution(s) to this "problem"?
Thanks!
JT