> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ionworks.com/llms.txt
> Use this file to discover all available pages before exploring further.

# 2025 10 27

<Update label="October 27, 2025" description="Multi-dimensional interpolant editor, 2D data upload, and piecewise interpolation">
  ## Multi-dimensional interpolant editor

  The parameter interpolant editor now supports multi-dimensional x values, making it possible to view and edit parameters that depend on more than one variable — such as temperature and SOC — directly in Studio.

  [Find out more →](/build/interpolants)

  ## 2D interpolant data upload

  Users can now upload 2D interpolant data, with the backend automatically interpolating to a regular grid. This simplifies working with experimentally measured parameter surfaces.

  [Find out more →](/build/interpolants)

  ## Piecewise interpolation

  The pipeline adds piecewise interpolation with both 1D and 2D support, giving more flexibility when fitting parameters with distinct regions of behavior.

  [Find out more →](/build/interpolants#interpolation-algorithms)

  <AccordionGroup>
    <Accordion title="Studio">
      **Improvements**

      * Added MSMR validation plots for pipelines from the API.
      * Improved data fit UI with loading state and timeout handling.

      **Fixes**

      * Fixed error handling for model creation with duplicated names.
    </Accordion>

    <Accordion title="Pipeline">
      **Improvements**

      * Added design objective custom parameters for evaluating by SOC or concentration.
      * Added SOC-based initialization for lumped SPM using voltage.
      * Allow additional arguments in data fit for cost logging and initial guess override.
      * Improved MSMR diffusion tolerance handling in low dUdx regions.
      * Improved optimizer performance and parallel execution during data fitting.
    </Accordion>
  </AccordionGroup>
</Update>