From: Richard Kreckel Date: Mon, 20 Dec 1999 20:06:53 +0000 (+0000) Subject: - Added a clarification about branch cuts. X-Git-Tag: release_0-5-0~85 X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=commitdiff_plain;h=db732c795526690b0a8e1f9c6ac5b50500f19fc6;hp=b08505c6c50a4c0310d096cb62774ccd53db7b0a - Added a clarification about branch cuts. --- diff --git a/doc/tutorial/ginac.texi b/doc/tutorial/ginac.texi index f044d2c9..aba77986 100644 --- a/doc/tutorial/ginac.texi +++ b/doc/tutorial/ginac.texi @@ -1105,8 +1105,16 @@ gamma(x+1/2) -> gamma(x+1/2) gamma(15/2) -> (135135/128)*Pi^(1/2) @end example -Most of these functions can be differentiated, series expanded and so -on. Read the next chapter in order to learn more about this. +@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. + +Besides evaluation most of these functions allow differentiation, series +expansion and so on. Read the next chapter in order to learn more about +this. @node Relations, Important Algorithms, Built-in functions, Basic Concepts