From b2613f4b583961c3b3fe46dc6ddd2bd1f1b2684c Mon Sep 17 00:00:00 2001 From: Alexander Frink Date: Mon, 21 Feb 2000 23:04:35 +0000 Subject: [PATCH 1/1] some words about the new function registration macro --- doc/tutorial/ginac.texi | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/doc/tutorial/ginac.texi b/doc/tutorial/ginac.texi index 73e1547b..1b81df50 100644 --- a/doc/tutorial/ginac.texi +++ b/doc/tutorial/ginac.texi @@ -1752,7 +1752,7 @@ instance are then handled automatically by @code{basic::diff} and @code{ex::diff}): @example -static ex cos_derive(const ex & x, unsigned diff_param) +static ex cos_deriv(const ex & x, unsigned diff_param) @{ return -sin(x); @} @@ -1773,14 +1773,20 @@ going to descibe how it expands, please consult your preprocessor if you are curious: @example -REGISTER_FUNCTION(cos, cos_eval, cos_evalf, cos_derive, NULL); +REGISTER_FUNCTION(cos, eval_func(cos_eval). + evalf_func(cos_evalf). + derivative_func(cos_deriv)); @end example The first argument is the function's name used for calling it and for -output. The second, third and fourth bind the corresponding methods to -this objects and the fifth is a slot for inserting a method for series -expansion. (If set to @code{NULL} it defaults to simple Taylor -expansion, which is correct if there are no poles involved. The way +output. The second binds the corresponding methods as options to this +object. Options are separated by a dot and can be given in an arbitrary +order. GiNaC functions understand several more options which +are always specified as @code{.option(params)}, for example a method +for series expansion @code{.series_func(cos_series)}. If no series +expansion method is given, GiNaC defaults to simple Taylor +expansion, which is correct if there are no poles involved (as is +the case for the @code{cos} function). The way GiNaC handles poles in case there are any is best understood by studying one of the examples, like the Gamma function for instance. In essence the function first checks if there is a pole at the evaluation point and -- 2.44.0