You don't need to know anything about genetic algorithms to use PerfectTablePlan. This page is just included in case you are interested.
It isn't possible to try every combination of guests and seats, because there are so many. Even just 25 guests can be assigned to 25 seats in 15, 511, 210, 043, 330, 985, 984, 000, 000 different ways. An efficient approach is required to search though the possible layouts to find a good solution in a reasonable time. PerfectTablePlan does this using a genetic algorithm.
A genetic algorithm works by mimicking the Darwinian process of natural selection over successive generations:
This process continues until a satisfactory solution is reached. In PerfectTablePlan you can choose to stop:
Because of the way a genetic algorithm works, it cannot be guaranteed to give a mathematically optimal answer - sometimes you can spot ways to improve the layout score with simple drag and drop. But if PerfectTablePlan were to use an approach that was guaranteed to give a mathematically optimal answer, it might take years to run. The PerfectTablePlan genetic algorithm will usually get close to an optimal solution very quickly.
The number of combinations for seating n guests in n seats is n! ( n factorial). This means that the difficulty of the problem rises very rapidly with the number of guests. For example:
25! = 150, 511, 210, 043, 330, 985, 984, 000, 000
50! = 3, 041, 409, 320, 171, 337, 804, 361, 260, 816, 606, 476, 884, 437, 764, 156, 896, 051, 200, 000, 000, 000
100! = 93, 326, 215, 443, 944, 152, 681, 699, 238, 856, 266, 700, 490, 715, 968, 264, 381, 621, 468, 592, 963, 895, 217, 599, 993, 229, 915, 608, 941, 463, 976, 156, 518, 286, 253, 697, 920, 827, 223, 758, 251, 185, 210, 916, 864, 000, 000, 000, 000, 000, 000, 000, 000
1000! has 2,568 digits. So don't be surprised if PerfectTablePlan takes a while to do an automatic layout for 1000+ guests!
More information on genetic algorithms:
