# How to eliminate the backward play in Export of Manipulate?

I find that the Export of Manipuate contains backforward play, see a simplified example:

Export["try.swf",
Manipulate[
Plot[Sin[2 x + φ], {x, 0, 10}], {φ, 0, 2 π}]]


You can see the problem in the SWF file. (I'm sorry that the exported SWF file cannot be uploaded here)

Actually, I have two questions here,

1. Is there any simple way to get a animation with only forward play? I can find nothing about this in the help documents.

2. Why is GIF not working in Export? That is to say, if I use Export["try.gif", Manipulate[...]],the exported file, otherwise an animation, is only a static picture actually.

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Try Export["yourfile.gif", Table[Plot[Sin[2 x + \[Phi]], {x, 0, 10}], {\[Phi], 0, 2 Pi, 2 Pi/20}]] –  belisarius Oct 29 '12 at 3:46
@ belisarius， you mean the gif can only be used in exporting a sequence of images? –  yulinlinyu Oct 29 '12 at 3:49
An animated GIF is just a series of GIFs ... you have to specify them one by one, yes –  belisarius Oct 29 '12 at 3:50
There was also a way by using Animate[]. I don't remember it right now –  belisarius Oct 29 '12 at 3:51

Both questions can be addressed by using a Table to generate the frames of the animation rather than Manipulate:

mov = Table[Plot[Sin[2 x + \[Phi]], {x, 0, 10}, PlotRange->All], {\[Phi], 0, 2 \[Pi],
2 \[Pi]/10}];
Export["movie.gif", mov]


Although this runs the animation in the forward direction only, it does repeat indefinitely. This technique is not limited to .gif, e.g., I use this to export .swf animations quite a bit.

You can of course control the smoothness of the animation by changing the increment 2 [Pi]/10 to something smaller if you like.

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Quick comment: better to use Export["movie.gif", Most[mov]] because your Table duplicates the starting point of the periodicity interval so that the movie appears to stop briefly when it completes one loop. –  Jens Nov 29 '12 at 17:23
Good point, although I left that repetitious frame there so he could see the animation was repeating (and when). This may not be desirable in his final application though. –  JohnD Nov 29 '12 at 17:31