Probability of an action happening in PHP.

[PhpNewb314]

I wonder how I can execute an action which has x% chance of happening, for instance a 31% chance of happening. How would I do that? I was thinking of using rand() to generate a number between 1 and 100 and if it is <= 50 (or whatever the percentage is, since that is going to vary based on the rank of the individual and hopefully fluctuate within ranks) then it is successful and if it is >50 then it isn't successful. 

 

 

This is just a preliminary idea and is definitely going to get more complex since I need to vary the percentage depending on rank and even slight fluctuation within rank (it is a game) but I was wondering about the best way to do this aspect of it. Is this the best way or is there a more efficient (or more elegant) way?

 

Thanks for any advice!

[.josh]

that's how you do it, yes.

 

function probability($p) {
  return $p >= rand(1,100);
}

if ( probability(31) )
  echo 'true';
else 
  echo 'false';

[PhpNewb314]

that's how you do it, yes.

 

function probability($p) {
  return $p >= rand(1,100);
}

if ( probability(31) )
  echo 'true';
else 
  echo 'false';

I thought that was probably the best way. Thank-you for confirming this, Josh!