Formulas

If you are not at all familiar with formulas, we suggest you take a look at getting started with formulas first. In this section, we’ll cover formulas more in depth. It will therefore be useful to do the guided tour before you start.

Formulas are the actions in the Berkeley Studio that the user does not directly see or interact with. They can be shown, for example through texts or questions, but by default they don’t. Aside from the most basic models, almost all models make use of formulas.

All formulas change variables. A variable can be anything. For example, in the Studio you can create a question called name that asks for the name of the user. The user can then enter ‘John’ and proceed. The variable name just got the value ‘John’! Formulas work the same way: you can create a formula called greetings that greets a user:

greeting the user
greeting the user

What this formula does is create a new variable called greetings. It assigns the value 'Greetings to you, ' + start.name + '!' to this variable. In this value, there are two pieces of text and another variable. Pieces of text always have to be entered within single quotes (’). So our variable greetings contains two texts: 'Greetings to you, ’ and ‘!’. In between the texts we put the variable name from the start node. Last but not least, the three elements are added together with the plus signs.

You can also do more advanced things. For example, imagine we also wanted to greet the user based on his or her gender. To do so, we first ask the gender of the user, then convert that into the right salutation and add that to the greeting. If you do not understand the (gender = 'Male') section to the right of the salutation-formula, please take a look at getting started with conditions.

greeting the user including gender
greeting the user including gender

It is important to understand what you can do with formulas. You can create and change numbers, texts, conditions and much more with them. For example, you can manipulate dates, assign scores to questions or add texts to user answers.

One important feature of formulas are functions. Functions are explained in detail in the next sections.