New to Expressions?
What are Expressions for?

Expressions offer a level of "light programming" that may be used to display dynamic content, driven by choices the End User makes while running an Experiment.
Use Expressions to:
- Perform simple computations in Worksheets.
- Generate default values and selection lists for Worksheets.
- Pull values from one Protocol’s Worksheet and populate cells in another Worksheet.
- Parameterize Tasks in Pipelines. Define patterns for filenames when automatically registering Files.
- Determine whether an Entity should transition to the next Workflow(s) in a Workflow Chain.
Example
Imagine that you need to retrieve a value from a LIMS cell. You could use the expression shown below to accomplish this. The items in bold are "parameters", the parts of the expression that you change to fit your needs as a modeler.
cell
(column: str, protocol: Optional[str] = None, generation: int = 0) → str
Parameters explained:
- column - the column containing the desired values.
- protocol - name of the Protocol containing the column. If protocol is None, the current Protocol is used.
- generation - where in the Entity-lineage to look for a value. 0 is "the uuid of the Entity in the current Protocol" -1 is the parent, -2 the grandparent, etc.
Read the docs
You can browse the entire Expressions API here:
Expressions API >
Expressions API >
Watch a demo

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