duplicate and activate Variant

Creates a copy of an existing variant (SSD file) within an SSP model and assigns it a new name.

A variant in SSP represents a specific configuration of a system (stored as an SSD file). By duplicating a variant, users can create an alternative configuration without modifying the original one. This is particularly useful for scenario testing, parameter studies, or creating multiple versions of a system with different inputs, parameters, or components.

Notes:

  • The duplicate is a deep copy of the variant — all systems, components, and parameter values are copied.

  • The duplicate can be modified independently of the original (e.g., by adding components, changing parameter values).

  • Duplicated variants must be explicitly added back to the model using model.add(variant).

  • The active variant of a model can be switched using model.activeVariantName = "VariantName".

Syntax:

variant_copy = model.variants['Variant-Name'].duplicate(new_name)
Parameters:

  • new_name (str): Name for the duplicated variant.

Returns:

  • (SSD): A new SSD object representing the duplicated variant.

Example usage:

from OMSimulator import SSD, SSP, Settings, CRef

Settings.suppressPath = True

# Create a new SSP model with a default variant
model = SSP(temp_dir="./tmp-duplicateVariant2/")
model.addResource("../resources/Modelica.Blocks.Math.Add.fmu")
model.addComponent(CRef("default", "Add1"), "resources/Modelica.Blocks.Math.Add.fmu")

# Set parameter values in default variant
model.setValue(CRef("default", "Add1", "u1"), 10.0)
model.setValue(CRef("default", "Add1", "u2"), 20.0)
model.setValue(CRef("default", "Add1", "k1"), 30.0)

# Duplicate the default variant as "Variant-B"
variantB = model.variants["default"].duplicate("Variant-B")
model.add(variantB)

# Modify parameter values in Variant-B
variantB.setValue(CRef("default", "Add1", "u1"), 100.0)
variantB.setValue(CRef("default", "Add1", "u2"), 200.0)

# Export SSP with both variants
model.export("duplicateVariant2.ssp")

# Load the model again and duplicate Variant-B as Variant-C
model2 = SSP("duplicateVariant2.ssp")
variantC = model2.variants["Variant-B"].duplicate("Variant-C")
model2.add(variantC)

# Modify Variant-C independently
variantC.setValue(CRef("default", "Add1", "u1"), -100.0)
variantC.addComponent(CRef("default", "Add2"), "resources/Modelica.Blocks.Math.Add.fmu")

# Switch active variant to Variant-C
model2.activeVariantName = "Variant-C"

# Add new component only to Variant-C
model2.addComponent(CRef("default", "Add3"), "resources/Modelica.Blocks.Math.Add.fmu")
variantC.setValue(CRef("default", "Add3", "u1"), -200.0)
variantC.setValue(CRef("default", "Add3", "k1"), -30.0)

# Print the structure of the model
model2.list()