Kostas,
I get that 2nd, 3rd, and 4th equation are inconsistent. Linsolve
returns a solution if I take out r(2),r(3), and r(4) equations. BTW, I
checked this on Maxima 5.9.0. My Maxima 5.11 is on a machine that is
not connected to the internet.
HTH,
Milan
* Kostas Oikonomou <ko at research.att.com> [2007-04-01 12:25:43 -0400]:
> Barton,
>
> Thanks for replying. I posted a simplified version of the problem,
> perhaps it was misleading. (By the way, I have 5.11.0 with SBCL 1.0.1)
>
> Here is the real problem: I have a 3x3 matrix with specified row and
> column sums, and I want to solve for 3 of the 9 elements:
>
> X : genmatrix(x,3,3)
> r(i) := sum(X[i,j],j,1,3)$
> c(j) := sum(X[i,j],i,1,3)$
> linsolve(
> [r(1)=10,r(2)=5,r(3)=3, c(1)=1,c(2)=3,c(3)=13],
> [x[1,1],x[1,2],x[1,3]]
> )
>
> Maxima encountered a Lisp error:
> Error during processing of --eval option "(cl-user::run)":
> The value 2 is not of type LIST.
> Automatically continuing.
> To reenable the Lisp debugger set *debugger-hook* to nil.
>
> Am I doing something wrong?
>
> Kostas
>
> Barton Willis wrote:
> > I get (Maxima 5.11.0):
> >
> > Inconsistent equations: (2)
> > -- an error. To debug this try debugmode(true);
> > (%i4) [r(1)=10, r(2)=5];
> > (%o4) [x[1,3]+x[1,2]+x[1,1]=10,x[2,3]+x[2,2]+x[2,1]=5]
> >
> > Looking at your equations
> >
> > (%i4) [r(1)=10, r(2)=5];
> > (%o4) [x[1,3]+x[1,2]+x[1,1]=10,x[2,3]+x[2,2]+x[2,1]=5]
> >
> > I see that the second equation doesn't depend on X[1,1]
> > or X[1,2]. So the error seems okay; for example
> >
> > (%i7) linsolve([x=6],[y]);
> > Inconsistent equations: (1)
> >
> > What is the output of build_info() ?
> >
> > Barton
> >
> > -----maxima-bounces at math.utexas.edu wrote: -----
> >
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