How can I create a specified amount of random values that all equal up to a specified number in PHP?

Question

For example, say I enter \'10\' for the amount of values, and \'10000\' as a total amount.

The script would need to randomize 10 different numbers that all equal up

Answer 1

I believe the answer provided by @JoeBlow is largely correct, but only if the 'randomness' desired requires uniform distribution. In a comment on that answer, @Artefacto said this:

It may be simple but it does not generate uniformly distributed numbers... 
Itis biased in favor of numbers of size 1000/10 (for a sum of 1000 and 10 numbers).

This begs the question which was mentioned previously regarding the desired distribution of these numbers. JoeBlow's method does ensure a that element 1 has the same chance at being number x as element 2, which means that it must be biased towards numbers of size Max/n. Whether the OP wanted a more likely shot at a single element approaching Max or wanted a uniform distribution was not made clear in the question. [Apologies - I am not sure from a terminology perspective whether that makes a 'uniform distribution', so I refer to it in layman's terms only]

In all, it is incorrect to say that a 'random' list of elements is necessarily uniformly distributed. The missing element, as stated in other comments above, is the desired distribution.

To demonstrate this, I propose the following solution, which contains sequential random numbers of a random distribution pattern. Such a solution would be useful if the first element should have an equal chance at any number between 0-N, with each subsequent number having an equal chance at any number between 0-[Remaining Total]:

[Pseudo code]:
Create Array of size N
Create Integer of size Max
Loop through each element of N Except the last one
    N(i) = RandomBetween (0, Max)
    Max = Max - N(i)
End Loop
N(N) = Max

It may be necessary to take these elements and randomize their order after they have been created, depending on how they will be used [otherwise, the average size of each element decreases with each iteration].