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Re: Animate Command and Vector Reference
Posted:
Jul 3, 2013 6:05 PM


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@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 > > > >



