Re: Re: Animate Command and Vector Reference
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- Subject: [mg131438] Re: Re: Animate Command and Vector Reference
- From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
- Date: Sat, 6 Jul 2013 05:03:26 -0400 (EDT)
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This is a scoping issue. The a used in the Animate iterator is local to the
Animate.
sub = {{a, 1}, {a^2, 1}};
OK, Bob, and why this
sub[a_]:={{a,1},{a^2,1}};
Animate[Graphics[{Line[{{0,0},sub[a][[1]]/.a->aa}]}],{{aa,-1,"a"},-1,1}]
In version 6 this worked perfectly. What happened since?
Best regards, Alexei
This is a scoping issue. The a used in the Animate iterator is local to the
Animate.
sub = {{a, 1}, {a^2, 1}};
Animate[
Graphics[{
Line[{{0, 0}, sub[[1]] /. a -> aa}]
}],
{{aa, -1, "a"}, -1, 1}]
Bob Hanlon
On Wed, Jul 3, 2013 at 4:59 AM, William Dickinson <
william.dickinson.0718 at gmail.com> wrote:
> I'm new to Mathematica and I want to create some animations. I tried
> something like this:
>
> sub = {{a, 1}, {a^2, 1}}
> Animate[Graphics[{Line[{{0, 0}, sub[[1]]}]}], {a, -1, 1}]
>
> and Mathematica give me an error. This error ( Coordinate {a, 1} should be
> a pair of numbers, or a Scaled or Offset form.) is not helpful.
>
> I know that I can fix this by changing sub[[1]] to {a,1}, but this is not
> a great solution. I have several places in the actual Animate command that
> use sub[[1]] (some in conjunction with a Table command) and it would be
> painful to do all of the replacing and rewriting. How can I make something
> like this work?
>
> I suspect that I'm missing something simple....
>
>
> Thanks in advance!
>
> Will
>
>
>
Alexei BOULBITCH, Dr., habil.
IEE S.A.
ZAE Weiergewan,
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L-5326 Contern, LUXEMBOURG
Office phone : +352-2454-2566
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e-mail: alexei.boulbitch at iee.lu