Rich:
Thanks for your suggestion:
> try this.
>
> load(draw);
>
> draw2d(color=blue, explicit(deltaX(1,2,3,Astep), Astep,1,6), color=red, point_size=.5,
> point_type=filled_circle,points([[1,1],[2,2],[3,3],[4,4],[5,5],[6,6]]));
>
> You will get red points and a blue curve.
I'm getting a blue line connecting the points, and no curve. Here is my
code. Note that I've made the change that Volker suggested, putting the
points into a named list. I also thought that maybe my use of the
underscore in the point names might be causing a problem, so I
eliminated it. I've also written the function dX with only one
variable:
dA1: 0.01;
dA2: 0.02;
dA3: 0.03;
dA4: 0.05;
dA5: 0.1;
dA6: 0.2;
dX1: 0.2;
dX2: 0.1667;
dX3: 0.1428;
dX4: 0.0714;
dX5: 0.02778;
dX6: 0.01515;
dAdX: [ [dA1,dX1],[dA2,dX2],[dA3,dX3],[dA4,dX4],[dA5,dX5],
[dA6,dX6] ];
P: matrix( [(1 / dA1^2), (1 / dA1), 1],
[(1 / dA4^2), (1 / dA4), 1],
[(1 / dA6^2), (1 / dA6), 1] );
S: matrix( [dX1],
[dX4],
[dX6] );
C: invert(P) . S;
dX(dA):= (C[1] / dA^2) + (C[2] / dA) + C[3];
load(draw);
draw2d(color=blue, explicit(dX(Astep), Astep,dA1,dA6),
color=red, point_size=.5, point_type=filled_circle,
points(dAdX) );