RE: Definite Integrals & Hidden Cells

• To: mathgroup at smc.vnet.net
• Subject: [mg34012] RE: [mg33990] Definite Integrals & Hidden Cells
• From: "David Park" <djmp at earthlink.net>
• Date: Fri, 26 Apr 2002 03:27:40 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

```DrBob,

A closed cell is not quite the same thing as a closed group. To open or
close a cell, select the cell bracket and use the menu item Cell\Cell
Properties\Cell Open and toggle it. You can also use Alt-c r c. It certainly
makes for a nicer looking notebook if graphics input cells, and other
calculations whose methods are a side issue are closed. It is too bad that
one can't open or close a SINGLE cell by double clicking the bracket. Of
course, closed cells can be evaluated even while they are closed. It would
be nice if one could actually add some text that did show instead of the
contents of the cell. Adding a cell tag doesn't work because that is also
closed with the cell. So you will often have to remind your reader to
evaluate the closed cell.

For the evaluation limits notation, I would first write a routine.

EvalLimits[top_, bottom_, var_:x][expr_] :=
(expr /. var -> top) - (expr /. var -> bottom)

Then you could write

Integrate[a*x^2, x]
%//EvalLimits[5, 3]
(a*x^3)/3
(98*a)/3

I brought in the Notation package and was able, without too many tries, to
define a notation using a \[VerticalLine] from the
CompleteCharacters\TextualForms palette. It worked, but is a little too
difficult to show in an email.

David Park

> From: DrBob [mailto:majort at cox-internet.com]
To: mathgroup at smc.vnet.net
>
> I've long been looking for a way to do two fairly simple things:
>
> 1) I've seen plots and other outputs where the code to generate them is
> hidden.  How do I do this?  I can hide all but the first cell of a
> group, but how do I hide ONLY the first cell?
>
> 2) I've often wanted to generate a vertical bar with upper and lower
> limits --- the usual math notation for the results of a definite
> integral --- but I haven't found a way to do it.
>
> Bobby Treat
>
>

```

• Prev by Date: RE: HoldForm Obscurities
• Next by Date: Re: DSolve validation
• Previous by thread: Definite Integrals & Hidden Cells
• Next by thread: Solving equations / real valued variables and parameters