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This version was released on 2023-Feb-28

Welcome to the 2023.1 release of Modelon Impact. This release is only applicable for Modelon Impact cloud and on-premises, for desktop users see information available below.

The update contains new features, updated libraries and addresses some usability issues.

We would also like to promote our workspace migration guide. It describes the process of upgrading your Modelon Impact Workspaces to use the new release of the Modelon Libraries or how to keep using 2022.2 version of the libraries and upgrade at a later point.

Below includes a detailed list of updated and new features in Modelon Impact.

New Features🔗

  • The FMU export now allows the selection of the target platform. Decide if the FMU should work for Windows x64 or Linux x64 platform.
  • For the FMU export for co-simulation you can now also choose the new Radau5ODE solver. Use this solver if the model contains many events and/or if the model has stability problems with CVode.
  • Support for svg icons – use svg image as icon for your model .


  • The component Properties panel (right-side bar) displays now also the dimension and size for non-scalar parameters and variables. This facilitates the entry of appropriate expressions, since you can now see which dimension is required.
  • Impact now fully supports vectorized connections, vectorized connectors and components in the UI (Diagram View)
  • Faster compilation for small models

  • Improved diagnostics support

    • Run-time diagnostics
      • See start values when a non-linear equation system fails to solve
    • Compilation error messages
      • Improved duplicate variables error messages
      • Support for annotation 'missingInnerMessage'
      • Add error message for parameter that depends on non-parameter
    • Improved Local balance checker
      • Additional check for choices annotations
  • HTML-like characters are now handled correctly in OCT compiler log

Changes in JupyterLab user environment for Modelon Impact cloud :🔗

  • JupyterLab updated to 3.5.3
  • Dash updated to 2.7.1, jupyter_dash package removed
  • VS code updated (code-server 4.9.1)
  • Removed legacy single-notebook Jupyter plugins
  • jupyter_nbextensions_configurator
  • jupyter-contrib-nbextensions
  • ~/.ipython directory removed from default Python path for security reasons. When installing additional packages with pip--target < directory > make sure to use sys.path.append(< directory >) or similar in your scripts and notebooks.

Notes on updates for Modelon Impact Desktop🔗

A new version will be available containing ONLY updates of the OPTIMICA Compiler Toolkit and libraries. Of the above, following improvements are included:

  • Improved diagnostics support
  • Faster compilation for small models