|
Size: 2812
Comment:
|
← Revision 136 as of 2022-03-30 19:10:54 ⇥
Size: 123
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 1: | Line 1: |
| #pragma section-numbers 2 | |
| Line 2: | Line 3: |
| ---------- * 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. Here is a small example: |
|
| Line 15: | Line 4: |
| {{{ # These comments are hints to Sage/Pyrex about the compiler and # libraries needed for the Givaro library: # #clang c++ #clib givaro gmpxx gmp m stdc++ cimport sage.rings.finite_field_givaro # Construct a finite field of order 11. cdef sage.rings.finite_field_givaro.FiniteField_givaro K K = sage.rings.finite_field_givaro.FiniteField_givaro(11) print "K is a", type(K) print "K cardinality =", K.cardinality() # Construct two values in the field: cdef sage.rings.finite_field_givaro.FiniteField_givaroElement x cdef sage.rings.finite_field_givaro.FiniteField_givaroElement y x = K(3) y = K(6) print "x is a", type(x) print "x =", x print "y =", y print "x has multiplicative order =", x.multiplicative_order() print "y has multiplicative order =", y.multiplicative_order() print "x*y =", x*y # Show that x behaves like a finite field element: for i in range(1, x.multiplicative_order() + 1): print i, x**i assert x*(1/x) == K.one_element() }}} To find out more, type {{{sage.rings.finite_field_givaro.FiniteField_givaro.}}} at the Sage prompt and hit tab, then use ?? to get more info on each function. For example: {{{sage.rings.finite_field_givaro.FiniteField_givaro.one_element??}}} tells you more about the multiplicative unit element in the finite field. |
See https://doc.sagemath.org/html/en/faq/ instead. |
