Programs in Q(uick)BASIC

for Applied Probability & Stochastic Processes

Here is a list of currently available program listings for this class. Unless marked otherwise, programs are written in QuickBasic and can run under DOS through QBASIC. Programs contributed by students may have been slightly edited.
• Sample programs to use as starting points in your own projects (for Chapter 1, except when marked otherwise).
  1. YAHTZEE.BAS Counting four of a kind outcomes in the game of Yahtzee.
     Also available:
     • C code by Ping Kuo
     • Pascal code
     • Three executable (ZIP-compressed) compiled from virtualy identical versions (Time all three C versus Pascal versus BASIC and see how much performance can be gained from other languages - Slow CPU recommended)
     • Simulation of the same probability by Masha Bowen. (How accurate a simulation answer is?)
  2. Select random subsets from any set, by N. V. Fitton. This is a good starting point for beginers to learn how to implement user input, and how to select subsets at random.
  3. Simple simulation TOSSCOIN.BAS of a 1000 tosses of a fair coin, and related fair (or not) coin tosser HEADS.BAS
  4. A game of craps: compare theoretical answer (as found by the computer!) with computer simulated probability in a game of craps by Chris Lowell.
  5. A simple example of blind search - find a max of a function of one variable. (More complicated, but also more interesting is traveling salesman demo below.
  6. DBLINT.BAS Double integral by Monte Carlo method (Chapter 2)
  7. A set of routines for poker simulation ( describing and printing cards, fast card shuffling,, recognizing at least a pair in a hand; marked possible extensions).
  8. Simulation drivers.bas of n cars arriving at an intersection, answering how often none has to stop.
  9. Two nice programs by Sonal Naik:
     • Simulate generic discrete random variable
     • Compare exact and simulated probabilities in geometric distribution.
• The following programs are more advanced, and should be treated as ``demonstrations" rather than easy-to-modify templates.
  1. RANDTOUR.BAS Demonstration of blind search for traveling salesman example. There is also a more user-friendly executable Windows version (ZIP-compressed) which lets you fly over any number of destinations in the USA.
  2. SALESMAN by NV Fitton is a nice DOS graphics traveling salesman solved by brute force..
  3. The probability of heads in tossing one coin is 50%. As the simulation size increases, the simulated answer should converge to theoretical value. Find out how often in 2n tosses of a coin, you get 50% of heads. (The answer involves pi!)
  4. LIMTHS.BAS Graphical illustration of important results: Law of Large Numbers, Poisson approximation, and Central Limit Theorem for Binomial trials (Chapter 5)
  5. FISH.BAS Watch the black fish disappear. (Illustration for fish-transfer problem in the notes).We have also Fortan and C-versions thanks to Anurag Gupta and Asad Rana.
  6. FIREWALK.BAS Two dimensional Wiener process makes neat pictures. (Chapter 6, or 10)

Instructions

QBASIC ProgramName /RUN

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