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Je viens de mettre un package debian 64 bits de la toute premiere version de la 1.2.3 dans testing. J'y ai fait quelques optimisations qui necessitent d'etre un peu testees avant de remplacer la 1.2.2 stable (mise a jour en 1.2.2-105 pour debian et windows).

Mise a jour 1.2.3-3, toujours des optimisations.
Par exemple (tire de http://nemocas.org/benchmarks.html) le polynome minimal ou caracteristique d'une matrice a coefficients polynomiaux:

La liste complete des benchmarks
Fateman
n:=30; f:=1+x+y+z+t; f:=symb2poly(f,[x,y,z,t]); p:=f^n:; time(q:=p*(p+1)); size(q);

Pearce
n:=12; f := symb2poly((1 + x + y + 2*z^2 + 3*t^3 + 3*u^5)^n,[x,y,z,t,u]):; g := symb2poly((1 + u + t + 2*z^2 + 3*y^3 + 3*x^5)^n,[x,y,z,t,u]):; size(f); time(p:=f*g); size(p);

Bernoulli polynomials
n:=1000;series("t"); u := t + O(t^n); time(r:=(u*exp(symb2poly(x,[x])*u))*inv(exp(u)-1));

Polynomials over number fields:
x:=rootof(cyclotomic(20));f:=(3x^7 + x^4 - 3x + 1)*y^3 + (2x^6-x^5+4x^4-x^3+x^2-1)*y +(-3x^7+2x^6-x^5+3x^3-2x^2+x);p:=symb2poly(f,y,[]); time(s:=p^300);

Determinant over a field:
n:=80;a:=rootof(x^3+3x+1); m:=ranm(n,n,a):; time(d:=det(m)); evalf(d);det(evalf(m,20));

Determinant of a matrix over a polynomial ring
n:=40; m:=matrix(n,n,(j,k)->randpoly(x,3,-21)-x^3):; time(d:=det(m));

Linear solving over a polynomial ring
n:=20; m:=matrix(n,n+1,(j,k)->y^2*ranv(3,-21)*[x^2,x,1]+y*ranv(3,-21)*[x^2,x,1]+ranv(3,-21)*[x^2,x,1]):; time(t:=rref(m,keep_pivot)); normal((m[0..n-1,0..n-1]*t[0..n-1,n..n])-t[0..n-1,0..n-1]*m[0..n-1,n..n]);

Determinant over a commutative ring:
p := 2003*1009; n:=80; f(j,k):={ k:=rand(6); return randpoly(x,k) % p; }; m:=matrix(n,n,f); det(m);

Resultant:
GF(7,11,x); p:=factor(j^3+3*x*j+1); rootof(p):=y;f := (3y^2 + y + x)*z^2 + ((x + 2)*y^2 + x + 1)*z + 4x*y + 3;g := (7y^2 - y + 2x + 7)*z^2 + (3y^2 + 4x + 1)*z + (2x + 1)*y + 1;F:=symb2poly(f,[[z]]);G:=symb2poly(g,[[z]]);n:=12; Fn:=F^n:; GFn:=(G+Fn)^n:; resultant(Fn,GFn);

Minimal polynomial of a matrix over the integers
n1:=80; n:=2*n1; m:=ranm(n1,n1,-21):; M:=blockmatrix(2,2,[m,0*m,0*m,m]):; for j from 1 to 10 do p:=idn(n); q:=p; r:=rand(n); d:=ranv(1,-4)[0]; p[r]:=seq(d,n); p[r,r]:=1; q[r]:=seq(-d,n); q[r,r]:=1; M:=q*M*p; od:; M:; time(a:=pmin(M)); time(b:=pcar(m)); a-b;

Characteristic polynomial of a matrix over the integers
n:=80; m:=ranm(n,n,-21):; time(charpoly(m));

Minpoly over a finite field
n1:=40; n:=2*n1; GF(103,2); m:=ranm(n1,n1,g):; M:=blockmatrix(2,2,[m,0*m,0*m,m]):; for j from 1 to 10 do p:=idn(n); q:=p; r:=rand(n); d:=ranv(1,-4)[0]; p[r]:=seq(d,n); p[r,r]:=1; q[r]:=seq(-d,n); q[r,r]:=1; M:=q*M*p; od:; M:; time(a:=pmin(M)); time(b:=pcar(m)); a; a-b;

Minpoly over a gcd domain
n1:=10; n:=2*n1; m:=matrix(n1,n1,(j,k)->ranv(3,-21)*[x^2,x,1]); M:=blockmatrix(2,2,[m,0*m,0*m,m]):; for j from 1 to 10 do p:=idn(n); q:=p; r:=rand(n); d:=ranv(1,-4)[0]; p[r]:=seq(d,n); p[r,r]:=1; q[r]:=seq(-d,n); q[r,r]:=1; M:=normal(q*M*p); od:; time(p:=pmin(M)); size(p); horner(horner(p,y),M,y); time(b:=pcar(M,y,lagrange)); normal(b-horner(p,y)^2);

Mise a jour (la derniere de l'annee!) 1.2.3-7 avec encore quelques accelerations.