On Wed, Nov 11, 2009 at 7:39 PM, PackRat <[email protected]> wrote:
> I've already worked with this kind of thing:
>
>   load 'plot'
>   pi=: o. 1    NB. definition of PI
>
>   cos2=: 4 : 0
>     NB. syntax:  cyclelength cos2 timespan
>     2 o. (i. y) * +: pi % x
>   )
>
>   plot 100 cos2 100
>
> However, my math skills from 45 years ago aren't enough to figure out
> what the cos2 routine should look like for an ellipse instead of a
> circle.

Essentially, for the way you have things set up, nothing changes.

If you think of a circle as having points with x and y coordinates,
your plot would only show the y component of those coordinates.

If you think of an ellipse in the same frame of reference, the thing
difference between a circle and an ellipse is the scale factor used
for the x and y coordinates.

-- 
Raul
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