System

There are three important characteristics of systems:

1. Systems are made of parts, or elements:

A system consists of individual components or elements that work together to achieve a common purpose or goal. These elements can be physical entities, such as objects or organisms, or abstract entities, such as ideas or concepts. Each element has its own properties and characteristics, which contribute to the overall functioning of the system.

2. These elements are in interaction:

The elements within a system interact with one another. Interactions can take various forms, such as communication, exchange of information, energy transfer, or influence.

3. The interactions between elements result in new features of the whole: 

When the elements of a system interact with one another, they create emergent properties or features that are not present in the individual elements alone. These emergent properties are the result of the collective behavior and interactions of the elements within the system. It represent flow of information and materials.

• Interaction happens when A impacts B, at the same time B also impacts A.
• Positive feedback loops: the larger population, more birth occuring
• Negative feedback loop: stabilize positive feedback. Example: the larger population. reducing food supply.

Car and Human body as a whole is System

System Output

Environment for every patch of cell becomes difficult -> capture the compute environemnt in an output once every so many number of steps by writing the value of every single cell to an output file and visualize it in other form.

Aggregration:

• Individual : single agent, single patch -> where this agent been overtime, which agent infected. Able to check wheter the simulation model works as the concept model.
• Global : all agent, all environment -> all infected agent per day, recorded recovered number per day. Indicates of patches location as row and columns and infected level.

Three ways to collect information:

1. User interface: works well while developing your model and want to show it to your student, but when run the model again, previous number simulation is gone.
2. Output file: stor output in word and csv to make a visualization better. Creating an outoput file in code to store it in local file. This output can be printed.
3. Behaviour space: able to store experiments with many number of times.