{* *! version 1.0.2  15mar2007}{...}
    {cmd:atan(}{it:x}{cmd:)}
{p2colset 8 22 26 2}{...}
{p2col: Domain:}-8e+307 to 8e+307{p_end}
{p2col: Range:}-pi/2 to pi/2{p_end}
{p2col: Description:}returns the radian value of the arctangent of {it:x}.
{p_end}
{p2colreset}{...}
