Numbering Equations

One WordTips reader expressed a desire to number the various equations appearing in his document. The desire was to have the equation be centered on the page, and the equation's number appear at the right margin within brackets. When a new equation is added to the document, the subsequent equations should be renumbered.

There are a number of ways you can approach this problem, but the possible solutions can be broken down into two general methods. The first method accomplishes the numbering using a combination of tables and fields, and the second uses tabs and fields. If you want to use the table approach, you can do so as follows:

1. At the point where you wish to insert an equation, create a table with one row and three columns. Make the right column just wide enough to contain the number style you wish to use (for numbering the equation). Make the left-hand column the same width in order to balance the space left for the equation number. Format the table so its borders are not visible.
2. In the center column type your equation, using Equation Editor.
3. With the insertion point still located in the center column of your table, click on the Center tool on the formatting toolbar. This centers the equation in the column. (If you made your left and right columns the same width, as pointed out in step 1, then this also results in the equation being centered on the page.)
4. Position the insertion point in the right-hand column, then click on the Align Right tool on the formatting toolbar.
5. Type the left bracket that you want to appear around the equation number.
6. Choose Field from the Insert menu. Word displays the Field dialog box.
7. In the Categories list, choose Numbering. (Click here to see a related figure.)
8. In the Field Names list, choose Seq. The letters SEQ should appear in the Field Codes box at the bottom of the dialog box.
9. Click on the Field Codes box and make sure the insertion pointer appears at the end of the field.
10. Type a name for this sequence of numbers, such as Equation.
11. Click on OK. A number appears in your document at the right of your bracket.
12. Type the right bracket to finish out the equation number.

If you want to use tabs to accomplish the same task, you can easily do that, as well. For instance, let's say you are using 8.5 x 11 paper, with 1-inch left and right margins. In this case, you would follow these steps:

1. Position the insertion point where you want to insert the equation, then choose Tabs from the Format menu. Word displays the Tabs dialog box. (Click here to see a related figure.)
2. If there are any existing tabs in the paragraph, click on Clear All.
3. In the Tab Stop Position box, type the position of the first tab (3.25).
4. For an Alignment, select Center.
5. Click on Set.
6. In the Tab Stop Position box, type the position of the second tab (6.5).
7. For an Alignment, select Right.
8. Click on Set.
9. Click on OK to close the Tabs dialog box.
10. Press Tab to advance to the first (centered) tab stop, and insert your equation.
11. Press Tab to advance to the second (right-justified) tab stop.
12. Type the left bracket that you want to appear around the equation number.
13. Choose Field from the Insert menu. Word displays the Field dialog box.
14. In the Categories list, choose Numbering.
15. In the Field Names list, choose Seq. The letters SEQ should appear in the Field Codes box at the bottom of the dialog box.
16. Click on the Field Codes box and make sure the insertion pointer appears at the end of the field.
17. Type a name for this sequence of numbers, such as Equation.
18. Click on OK. A number appears in your document at the right of your bracket.
19. Type the right bracket to finish out the equation number.

The advantage of using the tab method (as just described) is that you can define a paragraph style that already has the two tab stops set. You can then format any paragraph with the style, and simply type your information. You can take it one step further and also save the brackets and sequence field as an AutoText entry. In this way you could very quickly enter your sequence numbers.

When you add new equations in the middle of your document, it is very possible that not all of your subsequent equations will automatically increment. If you want to make sure that all the sequence numbers are correct, you can select the entire document and press F9 to update the fields.