This might be what you are looking for?
atan2trivial=: _3 o. %~
atan2=: 0 { [: +. [: r.^:_1 j.
For the principal domain, atan2trivial matches atan2
1 (atan2trivial -: atan2) 2
1
However, atan2 can distinguish direction when x=0
0 atan2 1
1.5708
0 atan2 _1
_1.5708
I'd like more test cases, though. I've not been doing much trig recently,
and it's possible I made a mistake.
Maybe someone who has been working with this kind of math can judge from
what viewmat displays?
require 'viewmat'
viewmat atan2"0/~ i:100
Thanks,
--
Raul
On Tue, Mar 11, 2014 at 7:05 PM, EelVex <[email protected]> wrote:
> Is there an atan2 anywhere in some library?
>
> If not maybe we could add it?
>
> A simple start could be:
> atan2 =: +:@(_3&o.)@([ %~ ] -~ +/&.:*:)
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