XMILE Conversion

Overview

Veydra supports importing system dynamics models from tools that export to the XMILE standard. XMILE (XML Interchange Language for System Dynamics) is an open standard that enables model portability across different system dynamics platforms.

Supported Tools: Stella Architect, Stella Professional, Vensim, and any software that exports valid XMILE format.

Supported File Formats

Extension	Description
`.xmile`	Standard XMILE XML format
`.stmx`	Stella model files
`.xml`	Generic XML with XMILE structure
`.mdl`	Vensim model definition files

Model Elements Converted

The XMILE parser extracts and converts:

Stocks - Accumulator variables with initial values
Flows - Rate variables connecting stocks
Auxiliaries - Helper variables and calculations
Modules - Submodels with their connections
Simulation Settings - Time units, start/stop times, and time step (DT)

Function Support

Common system dynamics functions are automatically translated:

XMILE Function	Description
`PULSE`	Generate pulse at specified time
`STEP`	Step function
`RAMP`	Linear ramp
`DELAY1`, `DELAY3`	First and third-order delays
`SMOOTH`, `SMOOTHI`	Exponential smoothing
`MIN`, `MAX`, `ABS`	Basic math functions
`IF THEN ELSE`	Conditional logic
`TIME`	Current simulation time

How to Import

From the Web App

Navigate to your project or create a new one
Click Import Model or use the Upload XMILE option
Select your .xmile, .stmx, .xml, or .mdl file
Provide a name for your model (optional - defaults to filename)
Click Upload

The conversion runs automatically and creates:

A new project (if needed)
A model in Design Mode ready for editing
A linked GitHub repository for version control

Via API

curl -X POST https://api.veydra.io/model/upload-xmile \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -F "file=@your_model.stmx" \
  -F "model_name=My System Dynamics Model" \
  -F "description=Imported from Stella"

Response:

{
  "model_id": 12345678,
  "project_id": 87654321,
  "repository_url": "https://github.com/veydra-models/model-12345678",
  "message": "XMILE file uploaded successfully. Conversion job started."
}

Conversion Process

+-------------------+     +------------------+     +-------------------+
|   Upload XMILE    | --> |   Parse & Validate   | --> |   Convert to VMS  |
|   (.stmx, .xml)   |     |   Extract elements   |     |   Python format   |
+-------------------+     +------------------+     +-------------------+
                                                            |
                                                            v
                          +------------------+     +-------------------+
                          |   Ready to Run   | <-- |   Create Model    |
                          |   in Playground  |     |   & Repository    |
                          +------------------+     +-------------------+

After Import

Once converted, your model:

Opens in Design Mode - Review and edit the model structure
Has a GitHub Repository - Version control is automatically set up
Can be Simulated - Switch to Run Mode to execute simulations
Supports Collaboration - Share and collaborate with team members

Troubleshooting

Invalid XMILE File Error

The file must contain valid XMILE XML with either:

A <xmile> root element, or
A <model> element

Ensure your source tool exports in XMILE format, not a proprietary binary format.

Unsupported Functions

If your model uses functions not in the supported list, they may need manual adjustment after import. The conversion will preserve the original equation text for review.

Complex Module Structures

Models with deeply nested modules are supported but may require verification after import. Check the stock-flow diagram in the Model Playground to confirm connections are correct.

XMILE Standard Reference

For technical details about the XMILE format, see the official OASIS specification: XMILE v1.0 Specification

Getting Started

Platform Features

Model Playground

Simulation Components

Tools

Integrations

Development

Overview

Supported File Formats

Model Elements Converted

Function Support

How to Import

From the Web App

Via API

Conversion Process

After Import

Troubleshooting

Invalid XMILE File Error

Unsupported Functions

Complex Module Structures

XMILE Standard Reference

​Overview

​Supported File Formats

​Model Elements Converted

​Function Support

​How to Import

​From the Web App

​Via API

​Conversion Process

​After Import

​Troubleshooting

​Invalid XMILE File Error

​Unsupported Functions

​Complex Module Structures

​XMILE Standard Reference

Overview

Supported File Formats

Model Elements Converted

Function Support

How to Import

From the Web App

Via API

Conversion Process

After Import

Troubleshooting

Invalid XMILE File Error

Unsupported Functions

Complex Module Structures

XMILE Standard Reference