Could you please include a self-contained, reproducible example (ideally
minimal)? That might help us figure out the problem. It would also be
useful to report the version of Maxima you are using -- use bug_report() to
get that information.
By self-contained and reproducible, I mean that it can be run as a batch
file in a fresh Maxima and doesn't require the tester to guess at
appropriate parameter values, etc.
-s
On Mon, Nov 14, 2011 at 11:36, Fernanda Farias <feboccaccio at gmail.com>wrote:
> Dear list members,
>
> I have been trying to use "solve" with 24 equations and expecting maxima
> to give me 18 unknown variables. But when I try to do this all at once it
> does not work, all I get is "[ ]". For the simplest case, I can give the
> code which equations (about 3 or 6) are necessary for obtaining one
> variable correctly, but this is enough since I am looking for the general
> case.
>
> I wrote the equations as following and I give the values for 8 points
> (giving the total of 24 equations), for example:
>
> One given point:
> eq1: I(deltax,0) = f(i+1,j)$
> eq2: DxI(deltax,0) = dxf(i+1,j)$
> eq3: DyI(deltax,0) = dyf(i+1,j)$
>
> Equations:
>
> I(x,y):=f+dxf*x+dyf*y+(1/2)*(d2xf*x^2+2*dxyf*x*y+d2yf*y^2)+(1/6)*(d3xf*x^3+3*d2xyf*x^2*y+3*dx2yf*x*y^2+d3yf*y^3)+(1/24)*(d4xf*x^4+4*d3xyf*x^3*y+6*d2x2yf*x^2*y^2+4*dx3yf*x*y^3+d4yf*y^4)+(1/120)*(d5xf*x^5+5*d4xyf*x^4*y+10*d3x2yf*x^3*y^2+10*d2x3yf*x^2*y^3+5*dx4yf*x*y^4+d5yf*y^5)$
>
>
> DxI(x,y):=dxf+d2xf*x+dxyf*y+(1/2)*(d3xf*x^2+2*d2xyf*x*y+dx2yf*y^2)+(1/6)*(d4xf*x^3+3*d3xyf*x^2*y+3*d2x2yf*x*y^2+dx3yf*y^3)+(1/24)*(d5xf*x^4+4*d4xyf*x^3*y+6*d3x2yf*x^2*y^2+4*d2x3yf*x*y^3+dx4yf*y^4)$
>
>
> DyI(x,y):=dyf+dxyf*x+d2yf*y+(1/2)*(d2xyf*x^2+2*dx2yf*x*y+d3yf*y^2)+(1/6)*(d3xyf*x^3+3*d2x2yf*x^2*y+3*dx3yf*x*y^2+d4yf*y^3)+(1/24)*(d4xyf*x^4+4*d3x2yf*x^3*y+6*d2x3yf*x^2*y^2+4*dx4yf*x*y^3+d5yf*y^4)$
>
> Any ideas?
>
> Regards.
> --
>
>
>
>
>
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