Subject: ratinterpol does not reproduce rational function
From: andre maute
Date: Thu, 27 Dec 2012 02:23:31 +0100
Hi list,
I have the following test case
--- ratinterpol.mac ------------
display2d : false;
load(interpol);
h : makelist( [k,-2*(k+1)*(2*k+1)/(k*(k+2))], k,1,12);
ratinterpol(h,2);
--- ratinterpol.mac ------------
I get this unexpected behavior
--- output -------------
$ maxima -b ratinterpol.mac
Maxima 5.27.0 http://maxima.sourceforge.net
using Lisp SBCL 1.0.57-1.fc17
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.
STYLE-WARNING: redefining MAXIMA::$FILE_TYPE in DEFUN
(%i1) batch(ratinterpol.mac)
read and interpret file: /home/user/ratinterpol.mac
(%i2) display2d : false
(%o2) false
(%i3) load(interpol)
(%o3) "/home/user/opt/maxima/share/maxima/5.27.0/share/numeric/interpol.mac"
(%i4) h:makelist([k,(-2*(1+k)*(1+2*k))/(k*(2+k))],k,1,12)
(%o4)
[[1,-4],[2,-15/4],[3,-56/15],[4,-15/4],[5,-132/35],[6,-91/24],[7,-80/21],[8,-153/40],[9,-380/99],[10,-77/20],[11,-552/143],[12,-325/84]]
(%i5) ratinterpol(h,2)
Unable to compute the LU factorization
#0:
ratinterpol(tab=[[1,-4],[2,-15/4],[3,-56/15],[4,-15/4],[5,-132/35],[6,-91/24],[7,-80/21],[8,-153/40],[9,-380/99],[10...,r=2,select=[])(linearalgebra.mac
line 310)
-- an error. To debug this try: debugmode(true);
(%o5) "/home/user/ratinterpol.mac"
--- output -------------
Best Regards
Andre