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Decision Tree form - Completing the Decision tab (Basic format)

Record the if.. then.. logic of the decision tree in this array, which has three columns. The unlabeled columns are known as the comparison, action, and next value columns.

This help topic describes the basic format of the Decision tab. If you encounter a Decision tab that contains Evaluate Parameter or Evaluate property name, see Completing the Decision tab (Advanced format).

At run time, the system evaluates the if portion of the array, starting at the top row, and continues as described here until it reaches a Return statement. If the system processes all rows but does not reach a Return statement, it returns the Otherwise value.

If the Redirect this Rule? box on the Results tab is selected, this circumstance-qualified rule is redirected and this tab appears blank.

Understanding the rows

Each text box may contain a value, a comparison operation for two values, followed by an outcome. The comparison may be between two properties or between a property and a constant value.

Click a field to make controls for that row or field visible:

Field

Description

if / if value is

Enter a comparison using one of the six comparison operators <, >, =, !=, >= or <=.

The value may be a constant or a Single Value property reference.

This field is not visible if the action field is set to Otherwise.

(action)

Select an action from the selection list. The action you choose determines which branch of this decision tree the system follows at run time when the condition to its left is reached and evaluates to true. Select a keyword:

Keyword

Effect
Return

Causes this branch of the decision tree to end processing when reached. If the system finds a Return row to be true, the value in the right column of this row becomes the result of the decision tree evaluation.
Continue

Causes the next row of the decision tree to be nested within this branch, The system reflects the nesting by indenting the next row on the form display and changing the arrow to to point down to that indented row. The context for the continue statement is the same as for the current statement.
Call Decision Tree

Causes the system to evaluate another decision tree, identified in the next field.

This choice may not be present in all cases, depending on settings on the Results tab.

If, at run time, this decision table evaluates in a backward-chaining context (the AllowMissingProperties parameter to the method is true), the system evaluates the called decision tree in the same way.
Call Map Value

Causes the system to evaluate a map value, identified in the next field.

This choice may not be present in all cases, depending on settings on the Results tab.

If, at run time, this decision table evaluates in a backward-chaining context (the AllowMissingProperties parameter to the method is true), the system evaluates the called map value in the same way.
Call Decision Table

Causes the system to evaluate a decision table, identified in the next field.

This choice may not be present in all cases, depending on settings on the Results tab.

If, at run time, this decision table evaluates in a backward-chaining context (the AllowMissingProperties parameter to the method is true), the system evaluates the called decision table in the same way.
Otherwise

Select Otherwise only as the bottom, final choice in a set of alternatives, marking the final choice. The value in the right column of this row becomes the result of this decision tree evaluation.

(next value)

Identify a target based on the action value.

If you selected Return as the action and the Results tab is not blank, select one of the values listed on the Results tab.

Otherwise, enter a value or expression here that allows evaluation of the decision tree to continue. You can reference a property on any page, but be sure to enter any page you reference on the Pages & Classes tab. Enter a value that depends on the action value keyword:

  • Return or Otherwise — Enter an expression for the result of this decision tree when this row is the final one evaluated.
  • Call Decision Tree — Select another decision tree. The result of that rule becomes the result of this rule. (This choice may not be present in all cases, depending on settings on the Results tab.)
  • Call Map Value — Select a map value. The result of that rule becomes the result of this rule. (This choice may not be present in all cases, depending on settings on the Results tab.)
  • Call Decision Table — Select a decision table. The result of that rule becomes the result of this rule. (This choice may not be present in all cases, depending on settings on the Results tab.)

This input field does not appear when the action value is Continue.

Click the Open icon to open a referenced decision tree, map value, or decision table.
Expand icon

Click to access an optional array of properties and values. Click the Collapse icon to hide this array. (This choice may not be present in all cases, depending on settings on the Results tab.)

When the decision tree evaluates and this row is the source of the results, the system also recomputes the value of the target properties identified in this array. Order is significant.
Property Optional. Identify a property reference to be set.
Value Enter a value for that property.
Otherwise
Return

Optional. Enter an expression defining a value to return when the decision tree evaluation does not return another value. When the Allowed Results list on the Results tab is not blank, this field is required and limited to one of the constant values listed on that tab.

If this field is blank and no other return value is computed, the system returns the null value.

About Decision Trees

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