for example, (- 1) get 225
for example, (- 1) get 225
use arctan (y code x) and judge which interval to be in according to the quadrant
$$ \ frac {180} {\ pi*arccos (\ frac {x} {\ sqrt {x ^ 2 + y ^ 2}})} $$
when y is negative, you need to subtract the above value from 360
use the trigonometric function tan = y code x to inversely calculate the angle
and then judge the angle in the positive direction of the X axis (+ 0 , + 90 , + 180 , + 270 , respectively)
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