Using 13&o. as Tom suggested:
at=:13&o.
at j./~i:100
gives the same result with both viewmat and plot as
atan2"0/~ i:100
Don
On 11/03/2014 4:59 PM, Raul Miller wrote:
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,
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