Читать книгу Kinematics of General Spatial Mechanical Systems - M. Kemal Ozgoren - Страница 46

The double argument arctangent function, which is denoted as atan₂(η, ξ), is defined so that it satisfies the following identity for any ρ > 0.

(2.162)

The most characteristic feature of the function atan₂(η, ξ) is that it gives θ without any quadrant ambiguity in the following interval, whenever η ≠ 0 and ξ ≠ 0.

More specifically, the function atan₂(η, ξ) gives the outcome θ as follows depending on the values of the arguments η and ξ: