On 06/26/2012 01:55 AM, Henry Baker wrote:
> You already know that coeff(expression,var,n) doesn't work unless "expression" is expanded, which is ok, although minorly irritating.
>
> But it would be nice if coeff(expression,x*y,n)=coeff(coeff(expression,x,n),y,n), so that you could pick out the coefficients of (x*y)^n, where n is usually 1.
>
> Thus, if p = x^2 + 2 x y + y^2, coeff(p,x*y,1) should be 2. (It currently returns 0.)
>
> _______________________________________________
> Maxima mailing list
> Maxima at math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima
>
doesn't ratcoef() work?
[user at localhost ]$ maxima -b ratcoef.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(ratcoef.mac)
read and interpret file: /home/user/ratcoef.mac
(%i2) display2d : false
(%o2) false
(%i3) p:y^2+2*x*y+x^2
(%o3) y^2+2*x*y+x^2
(%i4) ratcoef(p,x*y,1)
(%o4) 2
(%o4) "/home/user/ratcoef.mac"