Define calculations

Use calculations to compute new information during the configuration process. Defined as arithmetic equations or formulas, they handle tasks such as cost estimation based on user input and calculating other dependent parameters.

For example, for a product made of metal, calculations can determine the area based on its length and width. Then, the pricing engine can use this calculated area to estimate the metal product cost.

Calculations are defined in the product knowledge base and compute the values of Dynamic Data Attributes (DDA) and Dynamic Symbolic Attributes (DSA) of the numeric type. However, you can perform assignments only on numeric DDAs.

Using basic BODMAS principles combined with arithmetic functions, calculations can handle anything from simple estimations to complex computations.

Create a calculation

1. Create a dynamic data attribute (DDA) of the numeric type.

2. Add the DDA to the product knowledge base.

3. Group the attributes in the product knowledge base.

4. In the knowledge base, go to the Calculations tab by following these steps:

   1. From the application left navigation area, select Products.
   2. Select a product.
   3. From the top navigation bar, select Knowledge Base.
   4. Select a knowledge base, then go to the Calculations tab.

5. Select to create a calculation.

6. On the Create New Calculation dialog, enter the following information:

   • Name—Enter a name for the calculation, for example the name of your dynamic attribute.
   • Arithmetic Expression—Enter an arithmetic expression including one or multiple numeric dynamic attributes. Use the $() syntax to add a dynamic attribute.

7. Create a knowledge base snapshot.

In the product configurator, users can't edit the value of the dynamic attribute, whose value is computed based on a calculation.

Calculation features

• Includes various checks such as cyclic dependency detection, cast exceptions, divide-by-zero exceptions, and unacceptable syntax validation.
• Includes several built-in functions from the Jexl library, such as substring() for strings and size() for various objects.
• Supports basic mathematical operators (+, -, *, /, %) and includes additional constants and custom functions.
• Allows nested function calls, for example, min(max(5, 2, pow(2, 3)), 20, 30).
• Unlike the conventional Java math library, we support dynamic variable lengths for custom functions. For example, you can calculate GCD, LCM, or AVG for multiple variables in a single function call, such as gcd(12, 24, 36, 40).

Calculation performance

All functions execute with an average duration of less than 0.1 ms.

We conducted the performance tests on a system with the following specifications:

• Processor: Core i5
• Memory: 8 GB RAM
• Operating system: Windows 10 Pro, 64-bit

We used a typical machine after startup, parameters, for example arrays, of up to 5 elements and relatively small integers and strings. Actual performance may vary based on specific use cases and system configurations.

Libraries

Constant library

The Math. prefix can use defined here functions, for example, Math.PIE, Math.E, or Math.EQ.

Standard constants

Conditional constants

Directional constants

Standard functions

Convergence functions

Statistical functions

Exponential functions

Trigonometric functions

Logarithmic functions

Casting functions

Check functions

Conditional functions

Special functions

Before you begin

• Keep special cases in mind when using these functions, such as NaN, +Infinity, -Infinity, and null, as they may return results like NaN, +Infinity, -Infinity, or other values depending on the case.

• Avoid passing one or more null arguments, as this typically results in NaN (or a default argument, if specified). We do not recommend providing NaN or null in arguments to prevent unexpected results.

• All function and constant names are case-sensitive and signature-sensitive. Follow the correct syntax and signatures to avoid errors.

• Functions with a single parameter of variable argument types (for example, Double..., String...) allow flexibility. You can pass either an array or variable arguments. For example, max(3,4,5) returns the same result as max([3,4,5]).

• Calculations are currently limited to the same knowledge base. You cannot access DAs from another product’s knowledge base or from parent/child attributes of a SalesItem. However, you can use Search Expressions to bridge this gap.

• Avoid using the SearchExpression method unless absolutely necessary. If you must use it, review the notes associated with it beforehand.

• The distinction between type and types keywords has been simplified for search expressions. Previously, type and types behaved differently, but now only the type keyword exists. It returns a collection of all object types, making the syntax more generic for various use cases. You can still retrieve a single type of object using the first keyword, as shown in the following table. When migrating legacy search expressions, update their syntax to align with this change.

  Old syntax	New syntax
  SalesItem.type.endsWith('Stamping')	SalesItem.type.first().endsWith('Stamping')
  SalesItem.types.ID	SalesItem.type.ID

Functions