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Symbols and Symbol Sets
1 - Symbols
Symbols have the following three attributes:
- a symbol (lowercase, no spaces or hyphens..)
- an associated text (free text)
- (internally) a unique identifier
Using symbols to ensure consistency in representation across Processes
The options in a Select question might involve concepts which have relevance not only in a single Process but across the whole Project.
You can ensure that you represent such concepts consistently across Projects by defining symbols at the Project level and choosing to use them within the Process as option values.
Using Symbols to compute with
Symbols can be used as the value of options in a select question select question
When the user responds to a select question, the resulting value is a set of symbols.
Using Symbols for translating system terms
2 - Reasoning with Sets
Reasoning with Sets in Processes
Let us create an example to show reasoning with sets.
Suppose you are creating a nutrition App, and you are interested in people’s diet.
Asking the user for their eaten_regularly set
Suppose you create a Process and ask the user the following multi-select question:
Let us give the value name eaten_regularly to this select question.
So the response value of this question will be the set of symbols associated with the options selected by the user.
Asking the user for their finds_expensive set
Suppose you ask a second question multi-select question with the same options (and importantly, the same associated symbols).
Let us give the value name finds_expensive to this select question.
And now compute
Maybe now you want to calculate: which foods are eaten even though considered expensive?
This will be the intersection of the two sets
How do we do this?
Defining and updating a set variable
Reasoning with symbols sets defined at Project level
We can also define symbols and sets project-wide, and reason with them.
For example, we could define Project Symbols for each of the foods, and define Project Symbol Sets with various combinations.
Here is an example of a set called foods containing symbols for the foods above
Within a Process, we can choose to associate Project-level symbols with options:
So when we are doing set calculations, we can make use of sets defined at the Project-level: