Hello! On Mon, Jul 02, 2007 at 01:42:14PM +0200, Markus Grabner wrote:

Hi!

Printing an indexed expression using an instance of the print_csrc_double class produces invalid C code (the same syntax that is used in the tutorial http://www.ginac.de/tutorial/Indexed-objects.html#Indexed-objects) in ginac-1.3.7. I understand that the index class in ginac is more powerful than the indexing facilities of the C language, but still I expected print_csrc_double to produce valid C code simply due to its name. So I added a few lines which handle the case of integer indices (numeric or symbolic) stored in the idx class (patch attached).

Thanks for a patch. Unfortunately it breaks API, so it is not suitable for GiNaC 1.3 as is. Here is my variant: [PATCH] print_csrc_double prints indexed expressions as a valid C code. This one is suitable for GiNaC 1.3 --- ginac/idx.cpp | 13 +++++++++++-- 1 files changed, 11 insertions(+), 2 deletions(-) diff --git a/ginac/idx.cpp b/ginac/idx.cpp index 972967d..10cca17 100644 --- a/ginac/idx.cpp +++ b/ginac/idx.cpp @@ -150,8 +150,17 @@ void idx::print_index(const print_context & c, unsigned level) const void idx::do_print(const print_context & c, unsigned level) const { - c.s << "."; - print_index(c, level); + if (is_a<print_csrc_double>(c)) { + c.s << "["; + if (value.info(info_flags::integer)) + c.s << ex_to<numeric>(value).to_int(); + else + value.print(c); + c.s << "]"; + } else { + c.s << "."; + print_index(c, level); + } } void idx::do_print_latex(const print_latex & c, unsigned level) const -- 1.4.4.4 And this one is for development branch: [PATCH] print_csrc_double prints indexed expressions as a valid C code. --- ginac/idx.cpp | 11 +++++++++++ ginac/idx.h | 1 + 2 files changed, 12 insertions(+), 0 deletions(-) diff --git a/ginac/idx.cpp b/ginac/idx.cpp index 80e66bc..8d0497f 100644 --- a/ginac/idx.cpp +++ b/ginac/idx.cpp @@ -37,6 +37,7 @@ namespace GiNaC { GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(idx, basic, print_func<print_context>(&idx::do_print). print_func<print_latex>(&idx::do_print_latex). + print_func<print_csrc>(&idx::do_print_csrc). print_func<print_tree>(&idx::do_print_tree)) GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(varidx, idx, @@ -161,6 +162,16 @@ void idx::do_print_latex(const print_latex & c, unsigned level) const c.s << "}"; } +void idx::do_print_csrc(const print_csrc & c, unsigned level) const +{ + c.s << "["; + if (value.info(info_flags::integer)) + c.s << ex_to<numeric>(value).to_int(); + else + value.print(c); + c.s << "]"; +} + void idx::do_print_tree(const print_tree & c, unsigned level) const { c.s << std::string(level, ' ') << class_name() << " @" << this diff --git a/ginac/idx.h b/ginac/idx.h index 930994d..d859b2e 100644 --- a/ginac/idx.h +++ b/ginac/idx.h @@ -96,6 +96,7 @@ public: protected: void print_index(const print_context & c, unsigned level) const; void do_print(const print_context & c, unsigned level) const; + void do_print_csrc(const print_csrc & c, unsigned level) const; void do_print_latex(const print_latex & c, unsigned level) const; void do_print_tree(const print_tree & c, unsigned level) const; -- 1.4.4.4 Hopefully I did not break anything :) Best regards, Alexei -- All science is either physics or stamp collecting.