atan2

Four quadrant inverse tangent

Information

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):

Syntax

y = atan2(u1, u2)

Inputs (2)

u1

Type: Real

Description: First independent variable

u2

Type: Real

Description: Second independent variable

Outputs (1)

y

Type: Angle (rad)

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