This information is part of the Modelica Standard Library maintained by the Modelica Association.

This function returns y = atan2(u1,u2) such that tan(y) = u1/u2 and y is in the range -pi < y ≤ pi. u2 may be zero, provided u1 is not zero. Usually u1, u2 is provided in such a form that u1 = sin(y) and u2 = cos(y):

y = atan2(u1, u2)

u1	Type: Real Description: First independent variable
u2	Type: Real Description: Second independent variable

y	Type: Angle (rad) Description: Dependent variable y=atan2(u1, u2)=atan(u1/u2)