Variables

User variables of a running code are exposed by the Project class through its variables collection. The Variable class provides an interface to monitor and modify these variables.

Listing variables

To list all user variables available in a project:

for variable in project.variables:
    print(variable.name, variable.type_name)

Reading and writing values

To read from or write to a specific variable by name:

# Read the current value and write back an updated value
value = project.variables["speed_ref"].read()
project.variables["speed_ref"].write(value + 25.0)

Waiting for variable conditions

To block script execution until a user variable reaches a specific threshold or condition:

dc_voltage = project.variables["Vdc"]

# Poll every 100 ms without a timeout until the condition is met
cockpit.wait_until(lambda: dc_voltage.read() >= 750.0, timeout=None, interval=0.1)

API Reference

class imperix.VariableCollection(cockpit: Cockpit, *, project_id: int | None = None, mac: str | None = None)

Variables belonging to a project. Accessed via project.variables.

list(*, timeout: float | None | UseDefaultTimeout = UseDefaultTimeout.TOKEN) → list[Variable]

Returns a list of the variables belonging to a project.

Parameters:

timeout – Maximum time to wait for a response in seconds.

Returns:

A list of Variable instances.

Raises:

InvalidStateError – If the project has no linked target.

class imperix.Variable(_collection: VariableCollection, name: str, type_name: str)

Represents a user variable.

name

Variable name shown by Cockpit.

Type:

str

type_name

Data type (float, int32, or uint32).

Type:

str

read(*, timeout: float | None | UseDefaultTimeout = UseDefaultTimeout.TOKEN) → Any

Reads the variable value.

Parameters:

timeout – Maximum time to wait for a response in seconds.

Returns:

Current variable value. The Python type depends on the user variable type.

Raises:
write(value: Any, *, timeout: float | None | UseDefaultTimeout = UseDefaultTimeout.TOKEN) → None

Write a value to the variable.

Parameters:

  • value – The value to write.

  • timeout – Maximum time to wait for a response in seconds.

Raises: