Readers are guided through modeling things like world population growth, infectious disease, bungee jumping, baseball flight trajectories, celestial mechanics, and more while simultaneously developing a strong understanding of fundamental programming concepts like loops, vectors, and functions.
Clear and concise, with a focus on learning by doing, the author spares the reader abstract, theoretical complexities and gets right to hands-on examples that show how to produce useful models and simulations.
Simulation mimics a real-life process to determine or predict the response of the entire system. This helps to understand the dependency of each part of the system, their relations, and interactions. The process of simulating in real life can be costly. Therefore, we build a model to solve costly and complex ideas efficiently. Building a simulation model in an institution or organization increases profit.
Monte Carlo simulation is a mathematical technique that helps estimate the probability distribution of various event outcomes. Based on those probabilities, the risk analysis team decides whether they are ready to take the risk. This technique repeatedly takes random numbers between the minimum and maximum limit and predicts its outcome. Usually, the sampling is done on a large scale, so we get all the likely outcomes. Then we plot the probability distribution using which risk analysts calculate the risk probability.
A simulation is a representation of a real-world system. One can use mathematical or computational models of this system to study how it works, or what happens when parts of it are changed. Simulations are used in airports, restaurants, mechanics, government agencies, and many other systems where poor resource allocation can lead to congestion, customer dissatisfaction, and critical transportation delays.
In Python, you can use the simpy framework for event simulation. First, take a quick look at how a simulated process would run in Python. Below is a code snippet from a simulation of a security checkpoint system. The following three lines of code set up the environment, pass all necessary functions, and run the simulation:
The time this takes could be one minute, two minutes, or three minutes. You want each moviegoer to spend a different amount of time at the cashier. To do this, you use random.randint() to choose a random number between the given low and high values. Then, for each moviegoer, the simulation will wait for the chosen amount of time.
After a resource is used, it must be freed up for the next agent to use. You could do this explicitly with release(), but in the code above, you use a with statement instead. This shortcut tells the simulation to automatically release the resource once the process is complete. In other words, once the ticket is bought, the moviegoer will leave, and the cashier will automatically be ready to take the next customer.
When a cashier is freed up, the moviegoer will spend some time buying their ticket. env.process() tells the simulation to go to the Theater instance and run the purchase_ticket() process on this moviegoer. The moviegoer will repeat this request, use, release cycle to have their ticket checked:
Each moviegoer either will or will not want to buy food, which you can store as the Boolean values True or False. Then, use the random module to have the simulation randomly decide whether or not this particular moviegoer is going to proceed to the concession stand:
You also might want to start your simulation with a few moviegoers waiting at the theater. There will probably be a few people ready to go as soon as the doors open! The manager says to expect around 3 moviegoers in line ready to buy tickets as soon as the box office opens. You can tell the simulation to go ahead and move through this initial group like so:
You use range() to populate the theater with 3 moviegoers. Then, you use env.process() to tell the simulation to prepare to move them through the theater. The rest of the moviegoers will make it to the theater in their own time. So, the function should keep sending new customers into the theater as long as the simulation is running.
These variables are the parameters that you can change to see how the simulation changes. If a blockbuster movie has customers lining up around the block, how many cashiers should be working What if people are flying through the box office but getting stuck at concessions What value of num_servers will help ease the flow
run_theater(): This function controls the simulation. It uses the Theater class blueprint to create an instance of a theater, and then calls on go_to_movies() to generate and move people through the theater.
Introduction to Modeling and Simulation with MATLAB and Python is intended for students and professionals in science, social science, and engineering that wish to learn the principles of computer modeling, as well as basic programming skills. The book content focuses on meeting a set of basic modeling and simulation competencies that were developed as part of several National Science Foundation grants. Even though computer science students are much more expert programmers, they are not often given the opportunity to see how those skills are being applied to solve complex science and engineering problems and may also not be aware of the libraries used by scientists to create those models.
The book interleaves chapters on modeling concepts and related exercises with programming concepts and exercises. The authors start with an introduction to modeling and its importance to current practices in the sciences and engineering. They introduce each of the programming environments and the syntax used to represent variables and compute mathematical equations and functions. As students gain more programming expertise, the authors return to modeling concepts, providing starting code for a variety of exercises where students add additional code to solve the problem and provide an analysis of the outcomes. In this way, the book builds both modeling and programming expertise with a \"just-in-time\" approach so that by the end of the book, students can take on relatively simple modeling example on their own.
The book culminates with a set of final project exercise suggestions that incorporate both the modeling and programming skills provided in the rest of the volume. Those projects could be undertaken by individuals or small groups of students.
Modeling and simulation are invaluable tools for businesses and organizations. It can help accurately predict outcomes, identify weaknesses and strengths, and provide insights into how to improve a system. It can be used to understand interactions, quickly test changes, and evaluate processes, policies, and strategies. This can reduce costs and project duration, identify potential issues, and help make more informed decisions.
Python is increasingly popular for a variety of applications due to its high-level, general-purpose nature and its wide range of libraries and packages. It is particularly well suited for modeling and simulation. We can use these powerful tools in various disciplines, from engineering and science to economics and sociology. They are used to study the behavior of a system and its components and to predict the outcome of certain events.
A simple example would be simulating the growth of a population. In this example, you would create a virtual population and assign it a starting number of individuals. Then, you could define a set of rules for how the population grows over time, such as a fixed rate of growth, competition for resources, or environmental factors. Then run the simulation and observe the outcome. This will help you understand the dynamics of population growth and how different factors can affect it.
By combining powerful libraries and frameworks, simulations can be created quickly and accurately. This can give insights into the behavior of complex systems and provide valuable data for decision-making.
The first step in building a simulation model is to define the problem. This involves identifying the components of the system as well as the interactions between them. Once the components and interactions are identified, the model can be constructed. This includes specifying the parameters of the model, such as its time step, the initial conditions, and the rules of the system.
The process of designing a simulation model starts by understanding the problem and the system that needs to be simulated. This includes collecting data, creating a model, and selecting the appropriate simulation techniques and tools. The goal is to create a model that accurately reflects the system being simulated.
After designing the model, the simulation is then tested and run. This can be done using a computer program or software. Depending on the complexity of the model, a variety of experiments may be necessary to obtain the desired results. Experiments involve changing the values of parameters and running the simulation multiple times.
After running the simulation, the model may need to be optimized. This is done to ensure that the model is accurate and efficient. This involves making adjustments to parameters to improve the accuracy of the model and to ensure that the model is running as efficiently as possible.
After optimizing the model, the results of the simulation need to be analyzed. This can be done manually or with the help of software programs. The analysis involves examining the simulation results to determine what happened and why.
Running a simulation is relatively simple in Python. Now all that we need is a function that specifies the parameters of the model, as well as the equations and rules that define the behavior of the system. Once this is done, the simulation can be run by calling the function with different inputs.
Simulation modeling is a powerful tool for understanding and predicting the behavior of complex systems. It is used in a variety of industries to help solve difficult problems. This article discusses the basics of simulation modeling and how it can be used in Python. We have also looked at how to build a simulation model, optimize it, analyze the results, and improve it. Finally, we have discussed simple random statistics along with an example of modeling and simulation. 59ce067264