I started polishing my code for the purpose of posting, but got carried away instead with a further Components enhancement. (I 'm using Plot Component qualities to allow reading of multiple points - entered by mouse selection - to be entered to denote a curve that must be transformed to a straight line.) ...but on vacation, I have no access to the code until next week. Similar to what Juan N suggested, I too use a 4th degee polynomial method. I have too many projects at 90% complete, since I often lose ihigh interest after solving the technical aspect to my satisfaction.

acer

I started polishing my code for the purpose of posting, but got carried away instead with a further Components enhancement. (I 'm using Plot Component qualities to allow reading of multiple points - entered by mouse selection - to be entered to denote a curve that must be transformed to a straight line.) ...but on vacation, I have no access to the code until next week. Similar to what Juan N suggested, I too use a 4th degee polynomial method. I have too many projects at 90% complete, since I often lose ihigh interest after solving the technical aspect to my satisfaction.

acer

I have a 2-player game engine, which I've used to program mancala and chess in maple. (the chess is weak because a strong engine needs more ply/sec than interpreted maple can do, and I haven't Compiled it yet.) A Blokus plugin wouldn't be hard. I used variants of alpha-beta/minimax & negamax tree-pruning algorithms for the engine. (mancala allows multiple moves/turn situations, making it more interesting. ) I'm on vacation with poor connectivity, so cannot write more this week. )

acer

I believe that, yes, it is an issue of a global, unassumed n versus a local, assumed n. But I think that it is the opposite situation, and that the SubMatrix result is the one with the global n.

An evaluation of the sub-Matrix is then what is needed, and that can be done with either copy or inplace semantics.

acer

I believe that, yes, it is an issue of a global, unassumed n versus a local, assumed n. But I think that it is the opposite situation, and that the SubMatrix result is the one with the global n.

An evaluation of the sub-Matrix is then what is needed, and that can be done with either copy or inplace semantics.

acer

@Alejandro Jakubi Yes, thanks Alejandro, I realized that that was the situation.

And, while "dynamic binding" of some sort might be nice for Maple, this present behaviour doesn't seem so good to me (and I don't recall seeing the Maple 9->9.5 behavioural change as documented).

It looks more unfortunate, that some rebinding affects ":-LinearAlgebra:-MatrixInverse" even after the initial binding of `MatrixInverse`. I would have thought that :-LinearAlgebra:-MatrixInverse was bound, "simpl'd", and no longer dynamic. (It was like that for the first 4 years of modules' existence in Maple.)

It pulls the rug out, unexpectedly. I think that the OP's situation demonstrates this.

@Alejandro Jakubi Yes, thanks Alejandro, I realized that that was the situation.

And, while "dynamic binding" of some sort might be nice for Maple, this present behaviour doesn't seem so good to me (and I don't recall seeing the Maple 9->9.5 behavioural change as documented).

It looks more unfortunate, that some rebinding affects ":-LinearAlgebra:-MatrixInverse" even after the initial binding of `MatrixInverse`. I would have thought that :-LinearAlgebra:-MatrixInverse was bound, "simpl'd", and no longer dynamic. (It was like that for the first 4 years of modules' existence in Maple.)

It pulls the rug out, unexpectedly. I think that the OP's situation demonstrates this.

@corregumucio Ok. It can still be as flexible, without actual assignment.

> restart:

> eqxy1:=x+2*y=4:
> eqxy2:=x^2+y^2=16:

> xysol:=solve({eqxy1,eqxy2},Explicit);
                               /    -12      16\ 
              {x = 4, y = 0}, { x = ---, y = -- }
                               \     5       5 / 

> x=eval(x,xysol[1]);
                             x = 4

> eqrsxy1:=s*x+y^2*r=11;
                               2       
                        s x + y  r = 11

> eval( eqrsxy1, [x=eval(x,xysol[1])] );
                               2       
                        4 s + y  r = 11

@corregumucio Ok. It can still be as flexible, without actual assignment.

> restart:

> eqxy1:=x+2*y=4:
> eqxy2:=x^2+y^2=16:

> xysol:=solve({eqxy1,eqxy2},Explicit);
                               /    -12      16\ 
              {x = 4, y = 0}, { x = ---, y = -- }
                               \     5       5 / 

> x=eval(x,xysol[1]);
                             x = 4

> eqrsxy1:=s*x+y^2*r=11;
                               2       
                        s x + y  r = 11

> eval( eqrsxy1, [x=eval(x,xysol[1])] );
                               2       
                        4 s + y  r = 11

And I guess I didn't give this shorter one before,

> restart:
> with(LinearAlgebra):
> with(Student):

> MatrixInverse(Matrix([[4]]));
Error, MatrixInverse is not a command in the LinearAlgebra package

acer

And I guess I didn't give this shorter one before,

> restart:
> with(LinearAlgebra):
> with(Student):

> MatrixInverse(Matrix([[4]]));
Error, MatrixInverse is not a command in the LinearAlgebra package

acer

Ahh. It looks like it all worked in Maple 9, and that my 2nd and 3rd examples changed behaviour starting with Maple 9.5.

acer

Ahh. It looks like it all worked in Maple 9, and that my 2nd and 3rd examples changed behaviour starting with Maple 9.5.

acer

The Standard GUI no longer seems able to display the intermediary objects with attributes on them. (That fact is hidden, if one immediately sorts them and returns the underlying attributes instead, in just a single command.) This seems to have changed between Maple 11 and 12.

acer

See here for a look at question 2.

acer