Problem with mathematica - i am new to this

[lavster]

problem with mathematica - i am new to this!

hi,

im trying to produce a manipulate graph where the controller type is the drop down menu. (or pop up menu). However, mathematica doesn't seem to like the range of my variables.

I have typed the following into mathematica:

Manipulate[ Plot[r^2 p[n, l, r], {r, 0, 30}, ColorFunction -> "RoseColors", PlotRange -> All,
PlotStyle -> {Thickness[0.008]}, AxesLabel -> {"r(a)", "probability"}], {n, 1, 4, 1}, {l, 0, n - 1, 1}, ControlType -> {PopupMenu}]

(where p is my predefined function that depends on n, l, r).

The error message is as follows:

"Manipulate::vstype: ControlType -> PopupMenu is not supported for the variable specification {l$$,0,n$$-1}. ControlType -> Manipulator will be used instead."

suggesting that it doesn't like my upper bound.

How can i get around this? is there a command i can use? i vaguely recall other ppl using the table function within the manipulate function but I am not sure how to do this either...

thanks

 

[Dale]

I would just delete the "ControlType->{PopupMenu}" specification. You will get sliders, but they will work just fine.

 

[lavster]

i was specifically asked to use the drop down menu. but i still can't get it. the sliders seem to make life a whole lot simpler...

 

[Dale]

Do you need a drop down menu for both, or could you use a drop down menu for n and a slider for l?

 

[Dale]

It is not very elegant, but I got this to work using nested Manipulates:

Manipulate[
Manipulate[
Plot[r^2 p[n, l, r], {r, 0, 30}, ColorFunction -> "RoseColors",
PlotRange -> All, PlotStyle -> {Thickness[0.008]},
AxesLabel -> {"r(a)", "probability"}], {l, 0, n - 1, 1},
ControlType -> {PopupMenu}], {n, 1, 4, 1},
ControlType -> {PopupMenu}]

 

[lavster]

thanks so much for that!