The Index lists all MATLAB LifeGenesis Help topics.
To learn how to use Help, choose Using Help from the Help menu.
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MATLAB LifeGenesis is based on the remarkable Life simulation rules developed by the mathematician John Horton Conway. (See History of Life.) MATLAB LifeGenesis includes both a Life simulator and a game based on Life that you can play against the computer.
Imagine that you are looking into a microscope and you see a grid pattern on a glass slide. Some of the squares on the grid are empty, and some contain live tiny organisms or cells. Some organisms seem to live a long time, while others die quickly.
On parts of the slide, new organisms spring to life. As new generations of cells live and die, they form patterns of shifting color.
This microscopic drama is based on a mathematical model following three simple rules, (see Rules of Life ) which determine, as each generation passes, who lives, who dies and where new life begins.
These rules are not meant to accurately model any particular life system. They are instead a mathematical abstraction which has fascinated game players for more than 20 years because of the wonderful patterns that emerge as enerations progress. From the chaos of a random distribution of cells eventually emerges unexpected symmetries or quirky behaviors.
For most players, the magic is that three simple rules of logic can yield such diversity and beauty.
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The object of the Game of Life is to remove all the red cells from the grid. The computer will try to remove all the blue squares. You and the computer take turns adding and deleting cells.
To Choose a Skill Level:
From the Game menu, choose Easy, Hard, or Very Hard.
To Add a Blue Cell:
Click the square where you want to add the cell.
To Delete a Red Cell:
Click the red cell you want to delete.
To Make the Computer Take its Turn:
Click the mouse anywhere in the window to compute a generation. The computer will take its turn (adding a red square and deleting a blue square) and the next generation will be computed.
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Each square on the Life grid can have up to eight neighboring squares; above, below, left, right, and four diagonal squares. It is the number of neighbors that each square has in one generation that determines its fate in the next. If a living cell is too crowded or too isolated, it dies. If an empty square has just the right conditions, it can spawn new life. Here, then, are the Facts of Life:
1. A living cell with fewer than two neighbors dies of isolation.
2. A living cell with more than three neighbors dies of overcrowding.
3. New life is generated in an empty square with exactly three neighbors.
These are the classic rules for Life. They are all applied simultaneously to determine each new generation. LifeGenesis extends this by allowing living cells to come in two varieties distinguished by their color. The only modification required to accommodate this is an addition to rule 3. In LifeGenesis, the new cell generated is the same color as the majority of its three neighbors.
Edge Effect
These Life rules make no mention of what happens when a pattern grows beyond the edge of the grid. In fact, the rules implicitly assume an infinite grid. Because there is no screen for infinitely sized screens, this option is not available, and patterns are subject to what is called the Edge Effect. Some implementations of Life wrap around to the other side of the grid. LifeGenesis uses the Columbus Rule; when patterns expand too far, they just fall off the edge of the world.
This edge effect means that patterns at the edges can have unusual behavior. This is only really interesting mathematically. It's still pretty to watch.
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This section contains helpful hints for playing LifeGenesis successfully.
To succeed at the Game of Life, you need to develop a feeling for how the patterns evolve. Spend some time exploring Life by drawing your own patterns, or studying and modifying the built-in ones.
As a human, you have two advantages over the computer. One is that you get to go first. New players especially have a hard time winning once the computer gets the upper hand, so make that first move count. The other is that you can identify patterns, while the computer doesn't even try to do that. As you gain experience, you will begin to notice familiar shapes that work.
If there are many cells on the grid, it can become very difficult to figure out all the possibilities. Try to keep the number of cells down.
Watch what the computer does on its turn. On the Very Hard skill level in particular, it can come up with some clever ideas.
This is useful for learning how to get out of tight spots, or how to destroy whole patterns with a single move. But remember, the computer has no long-term strategy and it will often keep making the same stupid mistakes.
The world first learned of John Conway's Life rules when they were presented in Martin Gardner's "Mathematical Games" column in the October 1970 issue of Scientific American. That and a follow-up article in February 1971 were enough to start amateur and not-so-amateur mathematicians scrambling to find new and interesting Life patterns and properties.
Remember that this was before the dawn of personal computers, so much of the early work was done by hand on paper and on Go boards. Early questions concerned topics like the eventual fate of various initial patterns. The famous "R Pentomino" is a five-cell pattern that finally settles down to an oscillator after 1,103 generations. Such long-lived patterns are called Methuselahs. A seven-celled Methuselah called Acorn lives for over 5,000 generations.
Other questions surrounded the theoretical existence of a Garden of Eden pattern, one that has no possible ancestor. Early proofs determined that such a pattern must exist within a grid 10,000,000,000 squares on each side. By 1974, two had been found, one of which has only 226 cells.
A newsletter devoted to Life research called Lifeline was published from March 1971 to September 1973. Articles on Life appeared in Byte magazine, IBM Research Reports, and even Time magazine (January 1974).
If you'd like to learn more about Life, a good place to start is Martin Gardner's "Wheels, Life and Other Mathematical Amusements" published in 1983 by W. H. Freeman and Company.