How do i compute frequency of the numbers in the range,let's say 10-19,using rand number generator array with 50 int?
I have this code so far:
$arr = array_fill(0, 50, NULL);
for ($i = 0; $i < 50; $i ++) {
$arr[$i] = rand(10, 19);
}
but not sure if rand() assigned correctly .Thanks for any solution.
Cheat. Write them to a file.csv, bring it into Excel or LibreOffice then...
http://exceluser.com/formulas/countifs-frequency-distributions.htm
Remember that there many types of Random. Linear, Gaussian, Normal and a few more. I love random for this. Which one do you want?
I use netbeans ide. And wanted to use just a php.Thanks
Hmm... The write to file and read it back is using too many resources and is not optimal.
I am not clear about your question. Do you mean you want to...
1) create a random generated number between a and b (inclusive) for an array size of 50
2) count frequency of each number between a and b in the array
2.1) AFTER the array is generated, OR
2.2) DURING the array is generated
3) when counting, you CAN or CANNOT use other built-in function
By the way, from PHP documentation stated, mt_rand($min, $max) gives a better result than rand($min, $max). Just for your information.
Taywin,tahnks for the idea.Yes you outlined the steps as i needed.
Here's a quickie I knocked up. I got interested in why array_multisort wouldn't work with number-based keys, so got a bit carried away:
<?php
function generateFD($min,$max,$total,$sort='number',$order='ASC')
{
$r = [];
for($i=0;$i<$total;$i++)
$r[] = mt_rand($min,$max);
$counts = array_count_values($r);
//NUMBER SORT (DEFAULT)
if(strtoupper($sort) == 'NUMBER')
{
if(strtoupper($order) == 'ASC')
{
ksort($counts);
}else{
krsort($counts);
}
return $counts;
}
//FREQUENCY SORT
//Unfortunately simple asort won't sort the numbers after the frequencies
//and array_multisort on numeric keys don't work
//So this is a workaround
$tmp = [];
$keys = array_keys($counts);
$vals = array_values($counts);
foreach($counts as $k=>$v)
$tmp[] = [$k,$v];
if(strtoupper($order) == 'ASC')
{
//FREQ (Lowest frequency first)
array_multisort($vals, SORT_ASC, $keys, SORT_ASC, $tmp);
}else {
//FREQ (Highest frequency first)
array_multisort($vals, SORT_DESC, $keys, SORT_ASC, $tmp);
}
$counts = [];
foreach($tmp as $v)
$counts[$v[0]] = $v[1];
return $counts;
}
$freqASC = generateFD(19,30,50,'freq');
$freqDESC = generateFD(19,30,50,'freq','DESC');
$numberASC = generateFD(19,30,50);
$numberDESC = generateFD(19,30,50,'number','DESC');
?>
<style>
table{border-collapse: collapse;}
tr th, tr td{border: 1px solid black;}
</style>
<table>
<tr>
<th>Sort by Frequency Order by ASC</th>
<th>Sort by Frequency Order by DESC</th>
<th>Sort by Number Order by ASC</th>
<th>Sort by Number Order by DESC</th>
</tr>
<tr>
<td><pre><?php print_r($freqASC);?></pre></td>
<td><pre><?php print_r($freqDESC);?></pre></td>
<td><pre><?php print_r($numberASC);?></pre></td>
<td><pre><?php print_r($numberDESC);?></pre></td>
</tr>
</table>
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