# Create a Derivation

To create a field or axis derivation:

Right-click the field or axis where you want to add the derivation and select either

**Derivations > Add Field Derivation**or**Derivations > Add Axis Derivation**(depending on whether you want to create a field or axis derivation).By default, the new field will be inserted to the right of the column or below the row/wafer you clicked on, but you can move it afterwards by dragging and dropping the field to a new position on the axis.

You can also change the default positioning of new derivations from the Options settings (

**Edit > Options > Totals**). See Options for more information.The

**Define Derivation**window displays.Enter the following details:

Field Description **Derivation Label**Enter a name for the new field. This will be displayed in the table. **Calculation Order**(Optional) Set the order of evaluation for this new field. If you have multiple derivations in your table, this determines the order in which they are evaluated.

For example, if you have a derivation in the row axis, and another one in the column axis, then the cell where the two derivations intersect can only display the results of one, so you need to tell the application which one to display.

The calculation order is also an important consideration if you are calculating percentages of fields and also using totals.

Fields with a lower number are evaluated first. Either enter a number or:

- Click
**Order Last**to set this derivation to be the evaluated last out of all currently defined derivations. SuperCROSS populates the**Calculation Order**field automatically. - Click
**Clear Order**to clear the**Calculation Order**field.

You can change the calculation order from the right-click menu after you create your derivation. Right-click a derivation and select

**Calculate First**or**Calculate Last**.**Decimal Places**Set the number of decimal places used for the derivation. You can choose from two options:

- Leave the
**Standard**check box selected. The derivation will use the number of decimal places defined for the table. - Clear the
**Standard**check box and enter a value between**-9**and**9**to set a specific number of decimal places for this field. A positive number means that the value is subjected to integer rounding.

**Derivation**Use this field to build the calculation. You can either type in the calculation or use the buttons at the bottom to add field values and mathematical operators/functions.

- To use a field value in the calculation, you must use the value identifiers (V1, V2, V3, etc). You can also add the field to the calculation by selecting it in the
**Values**list and clicking**Add to Expression**. - If you select two or more values from the list (use
**Ctrl-Click**or**Shift-Click**) and click**Add to Expression**, SuperCROSS will automatically add them as a sum. - To add mathematical operators, you can either type them in or click the buttons.
You can add mathematical and statistical functions by selecting them from the list and clicking

**Add**. For more information about the available mathematical and statistical functions, see Statistical and Mathematical Functions for Derivations.

**Check**When you have finished building your calculation, you can click **Check**to confirm that the syntax is mathematically correct.**Add Reference**(Optionally) Click

**Add Reference**to define a reference to a derivation calculation.The

**Define Reference**dialog displays. The options are different depending on whether you are adding the reference to a field derivation or an axis derivation.**Option****Field Derivation****Axis Derivation****Use Reference**Select either

**Standard**or**Block Percentage**:**Standard**- a total formula is used. When added to the table the field derivation displays as normal text data results.**Block Percentage**- a percentage formula is used. When added to table the field derivation displays as percentage data results.

Select whether to reference a derivation in a row, column, wafer, or cell (cell is the intersection of all reference items). **Values**Select a value from the list. Select a value from the list. **Field Reference Setting**Click to select the field to reference. n/a When you have finished defining the reference, click

**Add to Derivation**to add it to your derivation calculation.**Footnote**(Optionally) Enter some explanatory text to be displayed as a footnote. The footnote will appear at the bottom of the table whenever the derivation appears in the table.

Derivation footnotes display above any standard footnotes.

- Click
- Click
**OK**. SuperCROSS adds your derivation to the table.

If you save your table, then your derivations will also be saved.

Field derivations also become part of the recode of the respective field, and will be saved if you save the recodes.

If you want to modify the derivation after creating it, right-click it and select **Derivations > Edit**.

You can also delete the derivation: right-click it and select **Derivations > Delete**.