Returns the arc-tangent of z.
pub fn atan(z: anytype) Complex(@TypeOf(z.re, z.im))
pub fn atan(z: anytype) Complex(@TypeOf(z.re, z.im)) {
const T = @TypeOf(z.re, z.im);
return switch (T) {
f32 => atan32(z),
f64 => atan64(z),
else => @compileError("atan not implemented for " ++ @typeName(z)),
};
}