Is it possible to control the output of rand, for example if I just want rand to give me the output of the variable $roll1 with the value or number of 1 half the time out of the six possibilities when rand is ran or when the browser is refreshed, how does one accomplish that?
My code sucks but I am fighting to learn, I only get one every now and then, but it's not consistent, I want a 1 every time I refresh the page.
So If I refresh the page 6 times I should get a 1 out of the variable $roll1 three times, and the rest of the values for $roll1 should be random.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999开发者_开发百科/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
<title>loaded dice</title>
</head>
<body>
<h1>loaded dice</h1>
<h3>loaded dice</h3>
<?php
// loaded dice, should roll the number 1 half the time out of a total of 6.
// So if I refreshed my browser six times I should at least see three 1's for roll1.
$roll1 = rand(1, 6);
// Okay is it possible to divide rand by two or somehow set it up
// so that I get the the value 1 half the time?
// I am trying division here on the if clause in the hopes that I can just have
// 1 half the time, but it's not working,maybe some type of switch might work? :-(.
if ($roll1 == 3) {
$roll1 / 3;
}
if ($roll1 == 6) {
$roll1 / 6;
}
if ($roll1 == 1) {
$roll1 / 1;
}
// This parts works fine :-).
// Normal random roll, is okay.
$roll2 = rand(1, 6);
print <<<HERE
<p>Rolls normal roll:</p>
You rolled a $roll2.
<p>Rolls the number 1 half the time:</p>
<p>You rolled a $roll1.</p>
HERE;
// Notice how we used $roll1 and 2, alongside the HERE doc to echo out a given value.
?>
<p>
Please refresh this page in the browser to roll another die.
</p>
</body>
</html>
You could do something like this
if (rand(0,1))
{
$roll = rand(2,6);
}
else
{
$roll = 1;
}
You can't directly make rand() do that, but you can do something like this:
<?PHP
function roll(){
if(rand(0,1)) //this should evaluate true half the time.
return 1;
return rand(2,6); //the other half of the time we want this.
}
So if you want to guarantee that in the last 6 rolls their would always have been at least 3 ones, I think you would have to track the history of the rolls. Here is a way to do that:
<?php
if (array_key_exists('roll_history', $_GET)) {
$rollHistory = unserialize($_GET['roll_history']);
} else {
$rollHistory = array();
}
$oneCount = 0;
foreach($rollHistory as $roll) {
if ($roll == 1) {
$oneCount++;
}
}
if (6 - count($rollHistory) + $oneCount <= 3) {
$roll = 1;
} else {
if (rand(0,1)) {
$roll = rand(2,6);
} else {
$roll = 1;
}
}
$rollHistory[] = $roll;
if (count($rollHistory) > 5) {
array_shift($rollHistory);
}
echo '<p>Weighted Dice Role: ' . $roll . '</p>';
echo '<form action="' . $_SERVER['PHP_SELF'] . '" method="get" >';
echo '<input type="hidden" name="roll_history" value="' . htmlspecialchars(serialize($rollHistory)) . '" />';
echo '<input type="submit" value="Roll Again" name="roll_again" />';
echo '</form>';
Rather than call rand() twice, you can simply do a little extra math.
$roll = $x = rand(1,12)-6 ? $x : 1;
A slightly different solution. It isn't as elegant, but perhaps more conducive to loading the die more finely?
$i = rand(1, 9);
if($i<=3)
{
$num = 1;
}
else $num = $i-2;
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