<function name="atan2" parent="math" type="libraryfunc"> <description> functions like <page>math.atan</page>(y / x), except it also takes into account the quadrant of the angle and so doesn't have a limited range of output. <note>The Y argument comes first!</note> </description> <realm>Shared and Menu</realm> <args> <arg name="y" type="number">Y coordinate.</arg> <arg name="x" type="number">X coordinate.</arg> </args> <rets> <ret name="" type="number">The angle of the line from (0, 0) to (x, y) in radians, in the range -pi to pi.</ret>⤶ <ret name="" type="number">The angle of the line from (0, 0) to (x, y) in radians, in the left-open interval (-pi, pi]</ret>⤶ </rets> </function> <example> <description> atan( 1 ) and atan2( 1, 1 ) are both math.pi / 4 atan2( -1, -1 ) equals to ( (-3) * math.pi ) / 4 </description> <code> print( atan( 1 ) ) print( atan2( 1, 1 ) ) print( atan2( -1, -1 ) ) </code> <output> 0.7853981633974483 0.7853981633974483 -2.356194490192345 </output> </example>