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

 

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
)