[Resolved] variable for loops?

[lazzerous]

ok, lets say I have a multi-dimensional array such as this:

$optionsets[0][0] = "DC";
$optionsets[1][0] = "D";
$optionsets[2][0] = "A";
$optionsets[3][0] = "9";
$optionsets[3][1] = "15";
$optionsets[3][2] = "21";
$optionsets[3][3] = "25";
$optionsets[3][4] = "31";
$optionsets[3][5] = "37";
$optionsets[3][6] = "51";
$optionsets[4][0] = "P";
$optionsets[4][1] = "S";
$optionsets[5][0] = "5";
$optionsets[5][1] = "6";
$optionsets[5][2] = "S";
$optionsets[6][0] = "E";
$optionsets[6][1] = "C";

However, the number of option sets, along with the number of elements within each option set is completely dynamic.

With this in mind, how could I show all possible combinations of the elements, while always keeping them in order, and always showing a value for each option set?

if the number of option sets were static, i could just put a for loop within a for loop within a for loop, etc:

for ($i=0; $i<sizeof($optionsets[0]); $i++)
	{
	for ($j=0; $j<sizeof($optionsets[1]); $j++)
		{
		for ($k=0; $k<sizeof($optionsets[2]); $k++)
			{
			echo $optionsets[0][$i];
			echo $optionsets[1][$j];
			echo $optionsets[2][$k];
			echo "<br>\n";
			}
		}
	}

How can I do this without knowing the number of option sets?

I know I can just do a bunch of for loops within each other with if statements to see if that deep of an option set exists, but that's serverly sloppy and processer intensive.

Anyone have a better idea?

Thanks much in advance for any insight... I could really use it

Thank you,
-=Lazzerous=-

[AstroTeg]

You'll want to test it, but maybe the isset() function will work...

if(isset($myarray[$a][$b][$c]) == true)
{
// there's data here!
}

[lazzerous]

let's review...

"I know I can just do a bunch of for loops within each other with if statements to see if that deep of an option set exists, but that's serverly sloppy and processer intensive."

Now, does anyone have any other logical ideas?

[AstroTeg]

do you not know what $a and $b will be?

If you do, I'm saying you can execute that one line in 1 pass - just set $a, $b, $c (or whatever) to the value you want to test. So, if you know the values - bang! You're done. If you don't know the values, then you need to implement a search algorithm.

[lazzerous]

I'm not sure that you're understanding what I'm trying to accomplish here....

given this array:
$ar[0][0] = "A";
$ar[0][1] = "B";
$ar[1][0] = "C";
$ar[1][1] = "D";

I want this outputted:

AC
AD
BC
BD

meaning that I want all possible combinations of the elements echo'd out...

The problem I run into is that The number of option sets is dynamic.

Along with that, I dont want to hard code a hundred for loops all within each other, all with if statements to see if the array goes that deep.

Code like that is sloppy, difficult to update, and processor intensive.

There has to be an easier, more scalable way to do this.

[AstroTeg]

Can you redesign your arrays?

I'm thinking you're going to be stuck using for() loops. Or you create a class and put the data in objects. Then build your own function to put the objects together in the combination you prefer - although I believe you're still going to be coming pretty close to doing for() loops anyways. Having a class object would somewhat hide the mess though.

Although looking at your first code example, you're not nesting your for()s all that well. You might do this to make it a little easier:

for($a = 0; $a < count($optionsets); $a++)
  for($b = 0; $b < count($optionsets[$a]); $b++)
    echo $optionsets[$a][$b];

[AstroTeg]

Actually, for what you're doing, the above code probably won't do it.

I'm leaning towards rethinking your array setup. Is there a reason you have it configured as it is?

[lazzerous]

No real reason of the structure of the array. have a better idea?

The reasoning behind my code is this:

I'm designing a 'part builder' where the user will select some of the options from the option sets (drop down boxes), and then hit a button to generate all possible remaining combinations.
Before I can do that, I first have to figure out the logic behind generating all possible combinations - i can add in limiters later.

The reason why this needs to be capable if handling dynamic amounts of option sets, along with a dynamic number of options within each set, is that there will have to be about fourty part number generators.
It would be much easier to manage one script that just pulled info from the database.

Right now, since I'm still designing it, restructuring how the data is represented won't hurt anything.

What were you thinking would help with an array re-design?

btw - thanks for the help

[AstroTeg]

THAT was handy info! We have some options, but the first question would be this (kinda easy, but will determine how things flow):

From a user standpoint, is the expectation they click on a product and then are immediately presented a list of add-on items only available to that product? This would be a JavaScript solution (PHP dynamically builds the JavaScript)

Or when a user clicks on a product, they're taken to a 2nd page with all the add-on items available for that product? This would be a PHP solution.

Either way is very do-able. I think this design will go back to how you have the database designed. You'd want to pull out a list of all products and then a list of what add-on items belong to each product. I'm not sure if you have the database design etched out or not.

[lazzerous]

kind of....

the user will see a list of 5 to 15 dropdown boxes.

the user will select an option from some of the boxes.

Once they hit the 'Submit' button, it will auto-generate all possible remaining combinations, while not varying from the ones they have selected.

Could I pull the data from the db and populate js arrays/variables? sure.

I havent even created the db tables yet - wanted to get the logic down first, so everything can change, if necessary.

[AstroTeg]

I would think your database will need to know how a product is associated with its options (probably via a cross reference table / many-to-many join).

Sounds like a user will be able to identify the product's properties on the first page - which really just means they're specifying the query parameters to be used to produce the options for the 2nd page. So, using those parameters, you query the database for the rest of the items that still match. I'm not sure how many drop downs you will have for the 2nd page, but depending on how you setup your query, you can do some tricks with group by and order by to produce one query that generates all your drop downs (and or JavaScript code to flip drop down options when the user selects an item from a particular drop down).

Make sense? Its kind of difficult to say "this design is the way to go". You have a lot of elbow room right now which is really driven on how you want the site to flow and what the user experience should be and what data you're going to have to display. But from the looks of it, I'd say let your database queries do most of the work.

[lazzerous]

you're reading wayyyyy too much into this man

let's just go back to option sets, and options within those sets.

Our catalogue of items is set up differently than you'd think, and these numbers don't necessarily reflect items currently in our catalogue.

I have everything else covered - i just need to know how to go through a 2 (or is it 3...) dimensional arrayand show all possible combinations of the array while keeping all parent elements in the order they are placed within the multi-dim array.

know what I mean?

[jsim]

You can do this using a simple recursive function:

function show_options($index=0,$s='') {
  global $optionsets;

  if( $index > count($optionsets)-1 ) {
    echo $s."<br>\n";
    return;
  }

  for( $i=0; $i<count($optionsets[$index]); $i++ ) {
    show_options($index+1,$s.$optionsets[$index][$i]);
  }
}

show_options();

I don't test it but it seems to works ok.
Is that what you need?

[AstroTeg]

Hmm... A database would make life way easier...

$optionsets[0][0] = 'A';
$optionsets[0][1] = 'B';
$optionsets[1][0] = 'C';
$optionsets[1][1] = 'D';

for($a = 1; $a < count($optionsets); $a++)
  for($b = 0; $b < count($optionsets[$a]); $b++)
    for($c = 0; $c < count($optionsets); $c++)
      echo $optionsets[0][$c] . $optionsets[$a][$b];

So here you have the outer load $a starting at 1. This is going to define the row to start at for the 'C', 'D' part.

$b defines the actual elements 'C', 'D' by number.

$c is used because it appears you want to mate the first elements ('A', 'B') with all the other row's elements ('C', 'D'). So c$ loops through all the first row elements and pairs them up with the current row being worked on.

I haven't actually tested this so I'm not 100% sure this would work.

[lazzerous]

jsim - you hit the nail right on the freakin head man

THANK YOU!

-=Lazz=-