This is a repost,
to attract someone's attention, because i got no response.
Andre
On 08/24/2011 03:57 PM, andre maute wrote:
> Hi,
>
> I have the following test, with a sum depending on b2.
> For general b2 simplify_sum gives an incorrect value.
>
> Andre
>
> ------- test-simplify_sum-1.max -----------
>
> display2d : false;
>
> F(d,a1,k1,a2,k2,b2,l2) := block(
>
> [res:1],
>
> res : res/(b2-l2)!,
> res : res/l2!,
> res : res*(-1)^l2,
>
> res : res*(b2+l2+d-2)!,
> res : res/(l2+d-2)!,
>
> res : res*(k2+l2+d-2)!,
> res : res/(k2+l2+d-1+k1)!,
>
> return(res)
>
> );
>
> load("simplify_sum");
>
> s:sum(F(d,1,1,1,1,b2,l2),l2,0,b2);
> h : simplify_sum(s);
> h : factor(minfactorial(h));
>
> s:sum(F(d,1,1,1,1,2,l2),l2,0,2);
> h : simplify_sum(s);
> h : factor(minfactorial(h));
>
> ------- test-simplify_sum-1.max -----------
>
> ------- test-simplify_sum-1.txt -----------
>
> Maxima 5.19.2 http://maxima.sourceforge.net
> Using Lisp SBCL 1.0.40-1.fc14
> Distributed under the GNU Public License. See the file COPYING.
> Dedicated to the memory of William Schelter.
> The function bug_report() provides bug reporting information.
> (%i1) batch(test-simplify_sum-1.max)
>
> batching /home/user/progs/test-simplify_sum-1.max
> (%i2) display2d : false
> (%o2) false
> (%i3) F(d,a1,k1,a2,k2,b2,l2):=block([res:1],res:res/(b2-l2)!,res:res/l2!,
> res:res*(-1)^l2,res:res*(-2+d+l2+b2)!,res:res/(-2+d+l2)!,
> res:res*(-2+d+l2+k2)!,res:res/(k1-1+d+l2+k2)!,return(res))
> (%o3) F(d,a1,k1,a2,k2,b2,l2):=block([res:1],res:res/(b2-l2)!,res:res/l2!,
> res:res*(-1)^l2,res:res*(-2+d+l2+b2)!,res:res/(-2+d+l2)!,
> res:res*(-2+d+l2+k2)!,res:res/(k1-1+d+l2+k2)!,return(res))
> (%i4) load("simplify_sum")
> (%o4)
> "/home/user/opt/maxima/share/maxima/5.19.2/share/contrib/solve_rec/simplify_sum.mac"
> (%i5) s:sum(F(d,1,1,1,1,b2,l2),l2,0,b2)
> (%o5)
> 'sum((-1)^l2*(l2+d-1)!*(l2+d+b2-2)!/((b2-l2)!*l2!*(l2+d-2)!*(l2+d+1)!),
> l2,0,b2)
> (%i6) h:simplify_sum(s)
> (%o6) 0
> (%i7) h:factor(minfactorial(h))
> (%o7) 0
> (%i8) s:sum(F(d,1,1,1,1,2,l2),l2,0,2)
> (%o8) (d+1)!*(d+2)!/(2*d!*(d+3)!)-d!*(d+1)!/((d-1)!*(d+2)!)
> +(d-1)!*d!/(2*(d-2)!*(d+1)!)
> (%i9) h:simplify_sum(s)
> (%o9) (d+1)!*(d+2)!/(2*d!*(d+3)!)-d!*(d+1)!/((d-1)!*(d+2)!)
> +(d-1)!*d!/(2*(d-2)!*(d+1)!)
> (%i10) h:factor(minfactorial(h))
> (%o10) -2/((d+1)*(d+2)*(d+3))
> (%o10) "/home/user/progs/test-simplify_sum-1.max"
>
> ------- test-simplify_sum-1.txt -----------
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