Sage FAQ: Frequently Asked Questions

QUESTION: Is there anything so Sage can be made to automatically execute commands on startup?
ANSWER: Yes, just make a file $HOME/.sage/init.sage and it will be executed any time you start sage.

QUESTION: My Sage upgrade failed with missing gmp symbols on OSX 10.4. What can I do?
ANSWER: Moving a sage install on OSX 10.4 and then upgrading anything that is linked against NTL leads to link errors due to missing gmp symbols. The problem is the link mode with which the dynamic NTL is created. I have a fix, but I am currently verifying that it really fixes the issue. Everything that is linked against NTL needs to be recompiled, i.e. singular and cremona at the moment. To add to the confusion: This is not an issue on OSX 10.5. A fix for this issue went into 2.8.15, so please report if you see this with a more current Sage release.

QUESTION: Upgrading Sage went fine, but now the banner still shows the old version. How can I fix this?
ANSWER: Try doing sage: hg_scripts.merge() followed by sage: hg_scripts.commit().

QUESTION: I want to write some Pyrex code that uses finite field arithmetic but cimport sage.rings.finite_field_givaro fails. What can I do?
ANSWER: You need to give hints to Sage so that it uses C++ (both Givaro and NTL are C++ libraries) and it also needs the GMP and STDC C++ libraries. Use this code template:

{{{#clang c++ #clib givaro gmpxx gmp m stdc++

cimport sage.rings.finite_field_givaro cimport sage.rings.finite_field_ntl_gf2e}}}

faq