Venus Visible
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Hi, I am not sure whether I misunderstand something but can't gamma become 180 degree when Venus is
between Sun and Earth and then cos(180 degree) = -1? The following (100+ year old!) article
suggests 1 + cos(gamma) as a factor, but in that case minimum visible brightness wouldn't really make sense.
Oh, Ahm. Ignore my previous explanations even if you have seen it. Of course the formula is wrong and minimum doesn't make sense. I'll update problem statement shortly. Thanks!
UPD now it should be better. Very sorry for this confusion. I definitely shouldn't rely on making geometry in my head instead of using pencil and paper.
I am a bit confused by the example.
input
3
0.515 0.664 848
answer:
130 151 169
Shouldn't this be 0.848? Also, the problem asks for pair of values for each testcase - angle of maximum and minimum visible brightness,
which, first, doesn't make much sense (minimum brightness is the same angle for all radii, isn't it?) and, second, the example provides only three numbers, not six.
Vladimir, thanks a lot for helping to clean this up after my most stupid confusion with angle calculation :) The text is updated according to your hints!
I guess there is still something wrong
This sentence
angle alpha - between direction from Sun to Venus (green) - and direction from the Earth to Sun (horizontal, purple)
should be changed to
angle alpha - between direction from Sun to Venus (NONHORIZONTAL, PURPLE) - and ...
Ah, thanks a lot, so silly and amusing mistake of mine :) Hopefully now it is better!