ATAN(3G)

    .SH "NAME" atan - return the arc-tangent of the parameters
    .SH "DECLARATION"

            .HP u genType atan(genType y, genType x);

            .HP u genType atan(genType y_over_x);

    .SH "PARAMETERS"

        .PP y

                    Specify the numerator of the fraction whose arctangent to return.

            .RE
            .PP x

                        Specify the denominator of the fraction whose arctangent to return.

                .RE
                .PP y_over_x

                            Specify the fraction whose arctangent to return.

                    .RE

                .SH "DESCRIPTION"
                    .PP atan returns either the angle whose trigonometric arctangent is $y \over x$ or y_over_x, depending on which overload is invoked. In the first overload, the signs of $y$ and $x$ are used to determine the quadrant that the angle lies in. The value returned by atan in this case is in the range $[-\pi,\pi]$. The result is undefined if $x = 0$.
                    .PP For the second overload, atan returns the angle whose tangent is y_over_x. The value returned in this case is in the range $[-{\pi \over 2 },{\pi \over 2}]$.

                .SH "VERSION SUPPORT"
                    .TS allbox tab(:); lB cB s s s s s s s s s s s lB cB cB cB cB cB cB cB cB cB cB cB cB. T{ T}:T{ OpenGL Shading Language Version T} T{ Function Name T}:T{ 1.10 T}:T{ 1.20 T}:T{ 1.30 T}:T{ 1.40 T}:T{ 1.50 T}:T{ 3.30 T}:T{ 4.00 T}:T{ 4.10 T}:T{ 4.20 T}:T{ 4.30 T}:T{ 4.40 T}:T{ 4.50 T} l c c c c c c c c c c c c. T{ atan T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}

                .SH "SEE ALSO"
                    .PP sin(), cos(), tan()

                .SH "COPYRIGHT"
                    .PP Copyright © 2011-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. https://opencontent.org/openpub/.

COPYRIGHT
Copyright © 2011-2014 Khronos Group