On 10/24/07, Jaap Spies <[EMAIL PROTECTED]> wrote: > > It is not in matrix2.pyx, It is on the bottom of my first message and here > below. > > It uses some functions/methods present in matrix2.pyx: > rook_vector, permanental_minor, prod_of_row_sums, permanent.
I think you should submit a patch to Sage so that this code gets included standard. It could go somewhere in the combinat directory. Is it a sloane sequences? It shouldn't be in sage.all by default, but should be easy for users to import. > > >>>> increase the amount of swap you have in that box. Adding more physical > >>>> RAM will probably makes the problem go away, too. > >>> I rebooted with no succes. Same error using 50-60% of 1 GB memory. > >>> Swap space is 5 GB. > >>> Jaap > > > > Ok, I will investigate on a 32 bit box then. Could you give us > > distribution/gcc and so on please? It might be related to specific > > compilers. > > > Linux paix 2.6.22.9-91.fc7 #1 SMP Thu Sep 27 23:10:59 EDT 2007 i686 i686 i386 > GNU/Linux > > gcc (GCC) 4.1.2 20070925 (Red Hat 4.1.2-27) > > Jaap > > ------- > > ########################################################################## > # Copyright (C) 2006 Jaap Spies, [EMAIL PROTECTED] > # > # Distributed under the terms of the GNU General Public License (GPL): > # > # http://www.gnu.org/licenses/ > ########################################################################## > > """ > Usage from sage > > sage: attach 'dancing.sage' > > sage: dance(4) > h^4 - 2*h^3 + 9*h^2 - 8*h + 6 > > """ > > # use variable 'h' in the polynomial ring over the rationals > > h = QQ['h'].gen() > > def dance(m): > """ > Generates the polynomial solutions of the Dancing School Problem > Based on a modification of theorem 7.2.1 from Brualdi and Ryser, > Combinatorial Matrix Theory. > > See NAW 5/7 nr. 4 december 2006 p. 285 > > INPUT: integer m > > OUTPUT: polynomial in 'h' > > EXAMPLE: > sage: dance(4) > h^4 - 2*h^3 + 9*h^2 - 8*h + 6 > > AUTHOR: Jaap Spies (2006) > """ > n = 2*m-2 > M = MatrixSpace(ZZ, m, n) > A = M([0 for i in range(m*n)]) > for i in range(m): > for j in range(n): > if i > j or j > i + n - m: > A[i,j] = 1 > rv = A.rook_vector() > # print rv > s = sum([(-1)^k*rv[k]*falling_factorial(m+h-k, m-k) for k in > range(m+1)]) > print s > > > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
