To state the obvious the half tenant of alpha goes from
1/2 of the tan (alpha) for alpha=0°
To
1 for alpha=90°
So to get a good result for alpha=1°, just divide the tangent by 2
And for alpha= 89°
Calculate the arctan With very little accuracy,
Divide by 2 and calculate the tangent which should be very close to 1.
Last fiddled with by a1call on 20171109 at 20:07
