@tab exponential function
@item @code{log(x)}
@tab natural logarithm
+@item @code{Li2(x)}
+@tab Dilogarithm
@item @code{zeta(x)}
@tab Riemann's zeta function
@item @code{zeta(n, x)}
@cindex branch cut
For functions that have a branch cut in the complex plane GiNaC follows
-the conventions for C++ as defined in the ANSI standard. In particular:
-the natural logarithm (@code{log}) and the square root (@code{sqrt})
-both have their branch cuts running along the negative real axis where
-the points on the axis itself belong to the upper part.
+the conventions for C++ as defined in the ANSI standard as far as
+possible. In particular: the natural logarithm (@code{log}) and the
+square root (@code{sqrt}) both have their branch cuts running along the
+negative real axis where the points on the axis itself belong to the
+upper part (i.e. continuous with quadrant II). The inverse
+trigonometric and hyperbolic functions are not defined for complex
+arguments by the C++ standard, however. Here, we follow the conventions
+used by CLN, which in turn follow the carefully designed definitions
+in the Common Lisp standard. Hopefully, future revisions of the C++
+standard incorporate these functions in the complex domain in a manner
+compatible with Common Lisp.
@node Input/Output, Extending GiNaC, Built-in Functions, Methods and Functions