This article may be too technical for most readers to understand.(August 2016) |
| Vensim | |
|---|---|
| Developers | Ventana Systems, Inc. |
| Initial release | 1990 |
| Stable release | Version 9.3.2 / July 2022 |
| Written in | C |
| Operating system | Windows and OS X applications, Linux and iOS libraries |
| Type | Simulation software |
| License | Proprietary |
| Website | vensim |
Vensim is a simulation software developed by Ventana Systems. It primarily supports continuous simulation (system dynamics), with some discrete event and agent-based modelling capabilities. It is available commercially and as a free "Personal Learning Edition".
Vensim provides a graphical modeling interface with stock and flow and causal loop diagrams, on top of a text-based system of equations in a declarative programming language. It includes a patented method for interactive tracing of behavior through causal links in model structure (the patent expired in 2012), [1] [2] [3] as well as a language extension for automating quality control experiments on models called Reality Check. [4]
The modeling language supports arrays (subscripts) and permits mapping among dimensions and aggregation. Built-in allocation functions satisfy constraints that are sometimes not met by conventional approaches like logit. [5] It supports discrete delays, queues and a variety of stochastic processes.
There are multiple paths for cross sectional and time-series data import and export, including text files, spreadsheets and ODBC. Models may be calibrated against data using optimization, Kalman Filtering [6] or Markov chain Monte Carlo methods. Sensitivity analysis options provide a variety of ways to test and sample models, including Monte Carlo simulation with Latin Hypercube sampling.
Vensim model files can be packaged and published in a customizable read-only format that can be executed by a freely available Model Reader. This allows sharing of interactive models with users who do not own the program and/or who the model author does not wish to have access to the model's code base. [7]
Vensim is general-purpose software, used in a wide variety of problem domains. Common or high-profile applications include: