Simulistics Ltd

Simulistics Ltd

Simulistics develops and distributes Simile, modelling and simulation software for complex dynamic systems in the earth, environmental and life sciences. We use unique logic-based declarative modelling technology to represent the interactions in these systems in a clearly structured, visually intuitive way. Using Simile makes modelling a more productive task for scientific investigators. Models can be prepared more quickly, shared more easily and maintained more efficiently. Quicker than writing C++ or Fortran code, More expressive than other visual modelling software, Better structured than a spreadsheet.

Company details

2B Pentland Park, Loanhead , Midlothian , United Kingdom EH20 9PA United Kingdom

More Office Locations Locations Served

Business Type:
Software vendor
Industry Type:
Environmental Science and Research
Market Focus:
Globally (various continents)
Year Founded:


System Dynamics and object-based modelling and simulation software

Simile has a System Dynamics heart, like many other visual modelling and simulation software tools. However, with Simile, you also benefit from the following features:

  • Object-based representation, for handling disaggregation and individual-based modelling
  • Auto-generated C++ model code, for fast execution
  • Plug-and-play modules, supporting modular modelling, any part of a model can be extracted and used separately
  • Plug-in displays, allowing you to create graphics specific to your field
  • Declarative model representation, making it easy to manipulate the model in complex ways

Simulistics is a spin-out company from the University of Edinburgh. Formed to enable continued development of Simile. We work in close collaboration with several of our customers on research projects in the earth, environmental and life sciences. The understanding we have gained from this work of how models are created and used by a scientific community inspires the development of our general-purpose modelling software.

Simile is distributed through our e-commerce channel,, which also provides documentation, a discussion forum & supporting material.

We have seen steady growth in customer numbers all over the globe since launching our web site in April 2002. Simulistics was founded in November 2001, and the founders now run the company as members of the board of directors.

Simile was originally developed by researchers in the Institute of Ecology and Resource Management at the University of Edinburgh. As the popularity of Simile grew, continuing development of the software and supporting the growing number of users became too big a task, and was incompatible with the academic status. The team of developers has therefore left the University, and now operates as an independent company. Any profits from the company’s operations are shared with the University of Edinburgh, in proportion to its investment.

Visual models

Simile is a visual modelling environment, allowing you to draw the elements of your model, and the relationships between them. Using simple mouse actions, you can re-arrange the elements, annotate the diagram or add graphics. The key to creating the model is to add influences between related variables. This provides the model with a clear and self-documenting structure.

System Dynamics notation

System Dynamics notation is an intuitive and insightful way to express concepts about rates of change. By analogy with water tanks and pipes, the compartment/flow notation allows complex differential equations to be formulated and solved without any special mathematical skills.

Powerful equation language

Once the chains of influence in the model have been drawn, you can express the mathematical form of the relationships using Simile’s powerful equation language. This provides a comprehensive range of mathematical expressions as well as built-in constructs for handling arrays.


Simile is unique in providing a marriage of System Dynamics notation with object-based constructs. Crucially, this allows complex models to be expressed concisely and thus greatly extends the range of behaviours and systems that can be modelled.

Run simulations

Working with models is a two-step process: firstly, you describe your system using the graphical and mathematical tools provided; secondly, you simulate its behaviour over a period of time. Simile converts your description into fast efficient C++ code in order to simulate its behaviour. The C++ code can be useful in its own right, for example it can be incorporated into other programs.

Display results as graphs, tables or animations

Simile provides a range of tools for visualising the behaviour of the system, using graphs, tables or animations. You can design additional display tools using the templates provided, if necessary, or export your results to another program for analysis.

Declarative models

One of the most exciting possibilities about modelling in Simile is that models are stored as a set of declarations about the model structure, much like a blueprint for its design. This opens the door to thinking of a wide variety of ways in which the computer can assist the modelling process, beyond merely simulating the behaviour of the system.