Eldon Eller wrote: > The arc tangent of _1r1 is different from the arc tangent of 1r_1. >
atan=:_3&o.@:%~
atan2=:angle@:j.
(?0) (atan-atan2) (?0)
_1.11022e_16
1 (atan-atan2) _1
0
_1 (atan-atan2) 1
_3.14159
Best wishes,
John
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