How Can I Generate Weighted Random Numbers in PHP?

Weighted Random Number Generation in PHP

This question explores the challenge of generating random numbers while assigning different probabilities to specific ranges. In PHP, the mt_rand() function provides a way to generate random integers, but it doesn't allow for weighted results.

To overcome this limitation, you can use the concept of weighted probabilities. This approach involves creating an associative array where the keys represent the desired outcomes, and the values represent their respective weights. The total weight of all outcomes should sum up to the maximum weight possible.

To generate a random result based on the provided weights, you'll need to calculate a random value between 1 and the total weight using the mt_rand() function. Then, iterate through the weighted array and subtract the weight of each outcome from the random value. The first outcome where the random value becomes negative or zero is selected as the weighted random result.

The provided PHP function getRandomWeightedElement() implements this approach, allowing you to specify an associative array of weighted outcomes and return the corresponding random key. Note that the weights should be integers, and non-integer weights may require custom adaptations of this function.

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