MathGroup Archive 1998

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Numbered Equations?

  • To:
  • Subject: [mg11964] [mg11964] Re: Numbered Equations?
  • From: "P.J. Hinton" <>
  • Date: Fri, 17 Apr 1998 03:40:08 -0400
  • Organization: Wolfram Research, Inc.
  • References: <6ghm09$>

On 9 Apr 1998, Tom Jazbutis wrote:

> Has anyone had success in getting the numbered equation cell type to
> actually be numbered in the notebook?
> I've tried every possible permutation of the options that deal with
> automatic numbering increments, displays, etc....  All I've been able
> to achieve is a "(/)" appearing where I would expect an equation number
> to appear if I change an empty cell to a number equation and then paste
> my equation into the empty cell.  There is no documentation in the
> system for any of these various options.
> Wolfram: If you're going to make it damn near impossible to cut and
> paste into text processing documents, please give Mathematica
> documented text processing features.  Your text processing is almost as
> bad as you mathematical processing is good.

There are several style sheets that support a "NumberedEquation" cell

	ArticleClassic		ArticleModern.nb
	Classic.nb		Classroom.nb
	HelpBrowser.nb		Report.nb

Wherein the cell displays a counter value that is determined

If you paste these cells into a notebook which is set to one of the six
style sheets above, you should see that the first and second cells are
labeled with (1) and (2) respectively.

          RowBox[{"f", "(", "x", ")"}], " ", 
          RowBox[{"\[DifferentialD]", "x"}]}]}], TraditionalForm]], 

          RowBox[{"2", " "}]], "=", " ", 
            RowBox[{"2", " "}]], "+", " ", 
          SuperscriptBox["b", "2"]}]}], TraditionalForm]], 

The reason that a number automagically appears in these cells is because
the protoype for "NumberedEquation" has a CellFrameLabel option that
places a Cell with a CounterBox in the right hand side.

Here is an example of a cell with modified frame labels.  Paste it in a
notebook to see the effect of this option.

Cell["Here is a cell", "Text",
  CellFrameLabels->{{"Left", "Right"}, {"Bottom", "Top"}}]

Let's modify this example to create a Cell with a counter in the right
hand side, as is done in the style sheet.  We'll set all the strings
except for the "Right" one to read None.  

In place of the "Right" string, we could actually just drop in a "(1)"
or whatever equation number you prefer, but then you'd have to adjust
these values every time you moved things around.  This is why there are
CounterBox objects.  

CounterBoxes take a string argument, which is the style that is to be
used in determining the value.  CounterBoxes have to appear within
TextData expressions, and a TextData has to appear within a Cell
wrapper.  This example

	Cell[TextData[{"(", CounterBox["NumberedEquation"],")"}]

shows how you could create a label that computes the current numbering
value for the "NumberedEquation" style and then insert it between to
parentheses.  If entering this in by hand seems unappealing, there is a
way to get around this.

1) Create a "Text" style cell (Format -> Style -> Text).

2) Enter an opening parenthesis.  

3) Click on the menu sequence Input -> Create Automatic Numbering

4) On the dialog box, select the style of counter that will be used. 
The expandable scroll menu will give you a list of all counters
available from the style sheet.  Here, we choose "NumberedEquation". 
Click OK.

5) Enter a closing parenthesis.  

6) Unformat the cell (Format -> Cell)

7) Delete the last argument to the Cell, which should be 

		, "Text"

8) You can now copy and paste the unformatted cell expression into our
working cell expression.

If put all of this together, we can make a cell style with our own
custom counter and add it to our style sheet.

Cell[StyleData["MyCounter"], NotebookDefault, 
  CellFrameLabels->{{None, Cell[TextData[{"(",
    CounterBox["MyCounter"],")"}]]}, {None, None}}, 

This will make the "MyCounter" value available on the Create Automatic
Numbering Object dialog box.

One other thing you may need to do is to hack the counter value.  That
is, you may need to reset it back to a different number for the
purposes of different sections or chapters.  In that case, you can use
the CounterAssignments option to set the value.  

For example, let's say you wanted to have our counter above reset back
to zero every time we started a new section, then we could edit the
style sheet prototype for the Section style to set "MyCounter" back to

CounterAssignments->{{"Subsection", 0}, {"Subsubsection", 0}, 
  {"MyCounter", 0}} 

I hope that this brief exposition gives you some clues as to how the
numbering system operates. 

If I have somehow misunderstood your question, please let me know.

P.J. Hinton
Mathematica Programming Group  Wolfram
Research, Inc.        
Disclaimer: Opinions expressed herein are those of the author alone.

  • Prev by Date: Re: calculation
  • Next by Date: Re: Evaluate In Place
  • Prev by thread: Re: Numbered Equations?
  • Next by thread: ANNOUNCE: New german book on Mathematica 3