Re: N-nested For loops, with N variable - Best way to implement?
- To: mathgroup at smc.vnet.net
- Subject: [mg60767] Re: N-nested For loops, with N variable - Best way to implement?
- From: dh <dh at metrohm.ch>
- Date: Wed, 28 Sep 2005 01:41:02 -0400 (EDT)
- References: <dhau6j$irs$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi lost and lonely,
if you really want to work with loopps and not tensors, you may first
assemble the iterator and then put it into a table.
E.g. assume we have n loops from 1 to lim. Inside the loop we merely
print all the running indices:
n=3;
lim=2;
iter=Table[{i[k],lim},{k,n}];
Table[
Print[Table[i[k],{k,n}]]
,Evaluate[Sequence@@iter]]
Because Table has the attribute "HoldAll" you need the "Evaluate".
Because you want to splice the iterators into the parameter lits for
Table, you need the "Sequence".
sincerely, Daniel
lost.and.lonely.physicist at gmail.com wrote:
> Hello everyone
>
> I'd like to seek some advice regarding how to best implement N nested
> For loops such that
>
> (1) N is a variable - i.e. I tell Mathematica what N is and it does the
> For loop N times.
>
> (2) For each loop I want to do something like For[a_k=1,a_k<=A,a++,
> ...], k = 1,...,N and I want to use the all the running values
> {a_1,...,a_N} to do stuff within the innermost loop.
>
> Maybe there's even a way to do this w/o using For loops? Table maybe?
>
> Thanks for the advice.
>