How can I best generate a static array of random number on demand?

Question

An application I\'m working on requires a matrix of random numbers. The matrix can grow in any direction at any time, and isn\'t always full. (I\'ll probably end up re-imple

Answer 1

A pseudo-random number generator is essentially a function that deterministically calculates a successor for a given value.

You could invent a simple algorithm that calculates a value from its neighbours. If a neighbour doesn't have a value yet, calculate its value from its respective neighbours first.

Something like this:

• value_(0,0) = seed
• value_(x+1,0) = successor(value_(x,0))
• value_(x,y+1) = successor(value_(x,y))

Example with successor(n) = n+1 to calculate value_(2,4):

 \ x  0      1      2
y  +-------------------
 0 | 627    628    629
 1 |               630
 2 |               631
 3 |               632
 4 |               633

This example algorithm is obviously not very good, but you get the idea.