Topic: Math/Statistics - All possible combinations of a survey's answers :(

[shlomikalfa]

Hi,

I've this topic which deals with something similar but not exactly the same... As my question is a bit more difficult...

I'd like to know how to get all the possible answer results of a an online survey.

Ex:
Question1 - 1/2/3
Question2 - 1/2
Question3 - 1/2

All possible permutations of the above survey will be 3*2*2 (12) that i know...
What I need is to output all the possible results into a table...

Ex:
__________________
1,1,1  |  2,1,1  |  3,1,1 |
1,1,2  |  2,1,2  |  3,1,2 |
1,2,1  |  2,2,1  |  3,2,1 |
1,2,2  |  2,2,2  |  3,2,2 |
__________________|

I know i should use some recursive method for that... any idea ?!

Any help will be appreciated.

Thanks in advance,
SK.

[shlomikalfa]

no one ?!

[ignace]

post some more information regarding your database structure

[shlomikalfa]

Well... there isn't much more to it...

I have an obj with question in it: $all_question
Inside, it has the questions... each of them has several number of answers... (different count).

I want to be able to output all the possible combinations of $all_question.

I can't explain it any better than I already did i think ...

This is what i have so far:

$rules = 1; // At least 1 rule.

// First, calculate how many rules do we need to create.

foreach($all_question as $question) {

$rules *= $question->answer_count;

}

// Parse all rules.

$ruleArr = array();

$ruleArrStr = array();

$lastQ = count($all_question)-1;

$lastC = $lastQ;

for ($i = 0; $i < $rules; $i++){

// Set the array to work with.

for ($c = 0; $c < count($all_question); $c++){

$ruleArr[$i][$c] = 1;

}

$qn = 0;

$str = implode(', ', $ruleArr[$i]);

while(array_search($str, $ruleArrStr)!==false){

while($ruleArr[$i][$lastC] == $all_question[$lastC]->answer_count){

$lastC-=1;

if($lastC==0){break 2;}

}

$ruleArr[$i][$lastC] += 1;

$lastC = $lastQ;

$str = implode(', ', $ruleArr[$i]);

echo 'search: '.$str;

}

$ruleArrStr[$i] = implode(', ', $ruleArr[$i]);

}

echo "<br /><br />";

print_r($ruleArrStr);


It's not working ofc....

I'm trying to move backwards... like:
1,1,1,1
1,1,1,2
1,1,1,3
1,1,2,1
1,1,2,2
1,1,2,3
........

[kathas]

$n = count($all_question)-1;
$answers = array();
$answer = array_fill(0,$n,1);
$change = $n;

while ($change > 0 || $answer[$change]<$all_question[$change]->answer_count)
{

if ($answer[$change]<$all_question[$change]->answer_count)
{
$answer[$change]++;
$answers[] = implode($answer,',');
$change = $n;
}
else
{
$answer[$change]=1;
$change--;
}


}



I tested it with this output.
The first question has 3 answers
second has only 1
third 2
4th 3

Code: [Select]

Array
(
    [0] => 1,1,1,1
    [1] => 1,1,1,2
    [2] => 1,1,1,3
    [3] => 1,1,2,1
    [4] => 1,1,2,2
    [5] => 1,1,2,3
    [6] => 2,1,1,1
    [7] => 2,1,1,2
    [8] => 2,1,1,3
    [9] => 2,1,2,1
    [10] => 2,1,2,2
    [11] => 2,1,2,3
    [12] => 3,1,1,1
    [13] => 3,1,1,2
    [14] => 3,1,1,3
    [15] => 3,1,2,1
    [16] => 3,1,2,2
    [17] => 3,1,2,3
)