Here is a simpler example (Maxima 5.20.1 GCL Windows)
load(interpol)$
ratinterpol([[1,1],[2,2]],1) => x --- OK
ratinterpol([[0,1],[2,2]],1);
0
0 has been generated
#0: ratinterpol(tab=[[0,1],[2,2]],r=1,select=[])(interpol.mac line 324)
-- an error. To debug this try: debugmode(true);
compare:
subst(0,k,ratinterpol([[k,1],[2,2]],1)) => x/2+1 --- OK
-s
On Tue, Apr 6, 2010 at 08:19, andre maute <andre.maute at gmx.de> wrote:
> Hello Maxima Mailinglist,
>
> the following use of ratinterpol generates 0^0.
> Is this a bug or a feature?
>
> I have some hundred! similar ones!
> I only know that the expressions are rational functions that's all :-(
>
> Could this perhaps be done with pattern matching?
>
> Best Regards
> Andre Maute
>
> ------------------------------------------------------------------
> display2d : false;
>
> h00 : 1*(-1/((b3+1)*(2*b3-1)));
> h01 : 1*(-(4*b3+3)/((b3+2)*(2*b3-1)*(2*b3+3)));
> h02 : 1*(-6*(b3+1)*(2*b3+3)/((b3+2)*(2*b3-1)*(2*b3+5)^2));
> h03 : 1*(-2*(2*b3+3)*(4*b3+5)/((b3+3)*(2*b3-1)*(2*b3+5)*(2*b3+7)));
> h04 : 1*(-5*(2*b3+3)^2/((b3+3)*(2*b3-1)*(2*b3+7)*(2*b3+9)));
> h05 : 1*(-3*(2*b3+3)*(4*b3+7)/((b3+4)*(2*b3-1)*(2*b3+7)*(2*b3+11)));
>
> h0 :[
> [0,h00],
> [1,h01],
> [2,h02],
> [3,h03],
> [4,h04],
> [5,h05]
> ];
>
> load(interpol);
> ratinterpol(h0,1,varname='b2);
> -------------------------------------------------------------------
> ~$ maxima -b ratinterpol.max
> Maxima 5.19.1 http://maxima.sourceforge.net
> Using Lisp SBCL 1.0.18.debian
> 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(ratinterpol.max)
>
> batching /home/user/ratinterpol.max
> (%i2) display2d : false
> (%o2) false
> (%i3) h00:1*(-1)/((1+b3)*(2*b3-1))
> (%o3) -1/((b3+1)*(2*b3-1))
> (%i4) h01:1*(-(3+4*b3))/((2+b3)*(2*b3-1)*(3+2*b3))
> (%o4) (-4*b3-3)/((b3+2)*(2*b3-1)*(2*b3+3))
> (%i5) h02:1*(-6*(1+b3)*(3+2*b3))/((2+b3)*(2*b3-1)*(5+2*b3)^2)
> (%o5) -6*(b3+1)*(2*b3+3)/((b3+2)*(2*b3-1)*(2*b3+5)^2)
> (%i6) h03:1*(-2*(3+2*b3)*(5+4*b3))/((3+b3)*(2*b3-1)*(5+2*b3)*(7+2*b3))
> (%o6) -2*(2*b3+3)*(4*b3+5)/((b3+3)*(2*b3-1)*(2*b3+5)*(2*b3+7))
> (%i7) h04:1*(-5*(3+2*b3)^2)/((3+b3)*(2*b3-1)*(7+2*b3)*(9+2*b3))
> (%o7) -5*(2*b3+3)^2/((b3+3)*(2*b3-1)*(2*b3+7)*(2*b3+9))
> (%i8) h05:1*(-3*(3+2*b3)*(7+4*b3))/((4+b3)*(2*b3-1)*(7+2*b3)*(11+2*b3))
> (%o8) -3*(2*b3+3)*(4*b3+7)/((b3+4)*(2*b3-1)*(2*b3+7)*(2*b3+11))
> (%i9) h0:[[0,h00],[1,h01],[2,h02],[3,h03],[4,h04],[5,h05]]
> (%o9) [[0,-1/((b3+1)*(2*b3-1))],[1,(-4*b3-3)/((b3+2)*(2*b3-1)*(2*b3+3))],
> [2,-6*(b3+1)*(2*b3+3)/((b3+2)*(2*b3-1)*(2*b3+5)^2)],
> [3,-2*(2*b3+3)*(4*b3+5)/((b3+3)*(2*b3-1)*(2*b3+5)*(2*b3+7))],
> [4,-5*(2*b3+3)^2/((b3+3)*(2*b3-1)*(2*b3+7)*(2*b3+9))],
> [5,-3*(2*b3+3)*(4*b3+7)/((b3+4)*(2*b3-1)*(2*b3+7)*(2*b3+11))]]
> (%i10) load(interpol)
> (%o10)
> "/home/puck/opt/maxima/share/maxima/5.19.1/share/numeric/interpol.mac"
> (%i11) ratinterpol(h0,1,varname = 'b2)
> 0^0 has been generated
> #0: ratinterpol(tab=[[0,-1/((b3+1)*(2*b3-1))],[1,
> (-4*b3-3)/((b3+2)*(2*b3-1)*(2*b3+3))],
> [2,-6*(b3+1)*(2*b3+3)/((b3+2)*(2*...,r=1,select=[varname =
> b2])(interpol.mac
> line 324)
> -- an error. To debug this try debugmode(true);
> (%o11) "/home/user/ratinterpol.max"
> -------------------------------------------------------------------
>
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