Each label is unique, whereas a name may be inadvertently assigned more than once for different purposes.

Output values are labeled sequentially. If you remove or insert an output, Maple automatically renumbers all equation labels and updates the equation label references.

If you change the equation label format, Maple automatically updates all equation labels and equation label references.

You cannot apply equation labels to the following:

Images, plots, sketches, and spreadsheets

Error, warning, and information messages

By default, equation labels are displayed. If equation labels are not displayed, verify the following:

From the Tools menu, select Options. In the Options dialog, click the Display tab. Ensure the Show Equation Labels feature is selected.

From the Format menu, select Equation Labels. Ensure that Worksheet is selected.

See the following example.

Enter an expression and press Enter. Note that the equation label is displayed to the right of the answer in the worksheet.

In a new execution group, enter another expression that must reference the output of the previous execution group.

From the Insert menu, select Label. Alternately, use the shortcut keys Ctrl+L (Command+L, Macintosh). The Insert Label dialog is displayed. Enter the label number and click OK.

The label is displayed in the expression. Press Enter to obtain the result.

In 1-D math, you can also apply an equation label using the Convert To Label Reference feature.

1. Type the desired label number in parentheses. For example, (1).

2. Select this expression, and from the Format menu, select Convert To>Label Reference.

Note: Simply typing (1) will not be understood to be a label reference. You must follow the steps described here or above to apply an equation label.

Label formatting is useful when execution groups are placed in subsections.

From the Format menu, select Equation Labels, then Label Display. In the Format Labels dialog, select a Label Numbering Scheme. (Optional) Enter a label numbering prefix.

You can switch between the label name and its reference content, as shown below.

Place the cursor immediately before or after a label reference, then from the Format menu, select Equation Labels, and then Label Reference.

You can set equation labels to be visible or hidden in an execution group, a selected area, or the entire worksheet.

The Format>Equation Labels>Execution Group menu item controls equation label display in an execution group.

The Format>Equation Labels>Selection menu item controls equation label display in a selected region.

A selected region may contain displayed and invisible equation labels. By using the Selection menu item (toggle switch), all equation labels in the region will be set to the toggled setting of the first equation label in the region.

The Format>Equation Labels>Worksheet menu item controls equation label display in a worksheet.

When you save a worksheet, the settings are also saved.

The Display Equation Labels check box in the Options dialog controls equation label display in the entire Maple session or environment. It does not control what areas of the worksheet display equation labels.

Notes:

(1) Due to the different way in which these objects are stored and modified inside Maple, label references should be avoided when referring to modules, procedures, tables, and arrays (but not the recommended Array data structure). Assign names to these objects instead.

(2) References to Matrix and Vector objects may be lost after a restart. This means that the commands to generate the objects must be re-executed before the Matrix browser is available for inspecting the contents of a large Matrix.