Loop through array and remove duplicates

Question

I have the following array for tire sizes:

    Array
    (
        [0] => 155
        [1] => 70
        [2] => 13
    )

    Array
    (
        [0] => 155
        [1] => 80
        [2] => 13
    )

    Array
    (
        [0] => 165
        [1] => 65
        [2] => 14
    )

    Array
    (
        [0] => 175
        [1] => 65
        [2] => 14
    )

    Array
    (
        [0] => 175
        [1] => 70
        [2] => 13
    )

    Array
    (
        [0] => 175
        [1] => 70
        [2] => 14
    )

and so on. Now I am creating a drop down so people can select the tire size they are searching for. so here is my PHP code:

include 'database.php';
$result = $mysqli->query('SELECT DISTINCT SKU_SIZE FROM SKU_DATA WHERE SKU_BRANDNAME = "'.$brand.'" ORDER  BY SKU_SIZE');

while( $row = $result->fetch_assoc()){
    $sku_size = $row['SKU_SIZE'];
    $chars = preg_split('/[^\d]/', $sku_size, -1, PREG_SPLIT_NO_EMPTY);

    echo "<option>".$chars[0]."</option>";

}

Now that code is just showing the first number in each array, for the very first drop down they select.

Right now it is showing 155, 155, 165, 175, 175 - and what I want it to do is just show the unique values so it would just show 155, 165, 175.

Update: Thanks! I got that part working. One quick question.. the order is not quite right, not sure what I am doing wrong. Here is a preview:

enter image description here

Jeff Lambert · Accepted Answer · 2011-10-04 14:31:42Z

2

Create an array and check to see if each value is in the array before outputting it. If it is not in the array, add it in before outputting.

include 'database.php';
$result = $mysqli->query(
    'SELECT DISTINCT SKU_SIZE 
    FROM SKU_DATA WHERE SKU_BRANDNAME = "'.$brand.'" 
    ORDER  BY SKU_SIZE'
);

$seen = array();

while( $row = $result->fetch_assoc()){
    $sku_size = $row['SKU_SIZE'];
    $chars = preg_split('/[^\d]/', $sku_size, -1, PREG_SPLIT_NO_EMPTY);

    if(in_array($chars[0], $seen))
        continue;

    $seen[] = $chars[0];
    echo "<option>".$chars[0]."</option>";

}

answered Oct 4, 2011 at 14:31

Jeff Lambert

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2 Comments

Sonny Over a year ago

I like this solution best because there isn't a second loop required.

Jeff Lambert Over a year ago

Depending on what the OP wants to do with the rest of his script, it may make good sense to have two loops, although he did not specify it in his post. This is true especially if he wants to use the results of the query again later on.

Luke · Accepted Answer · 2011-10-04 14:33:58Z

2

You can remove any duplicate unique items from an array using the array_unique() function.

EG:

$arrays = array(1,2,3) + array(1,2,3);

print_r(array_unique($arrays));

// Will print just: Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 )

answered Oct 4, 2011 at 14:33

Luke

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Comments

jancha · Accepted Answer · 2011-10-04 14:54:46Z

1

use this:

while( $row = $result->fetch_assoc()){
    $sku_size = $row['SKU_SIZE'];
    $chars = preg_split('/[^\d]/', $sku_size, -1, PREG_SPLIT_NO_EMPTY);

    $sizes[$chars[0]] = true;
}

ksort($sizes, SORT_NUMERIC);

foreach ($sizes as $size => $tmp){
    echo "<option value=\"$size\">$size</option>";
}

edited Oct 4, 2011 at 14:54

answered Oct 4, 2011 at 14:31

jancha

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3 Comments

Drew Over a year ago

Perfect, thank you! If you don't mind, I just updated my answer can you see what's going on with the ordering?

Luke Over a year ago

To make the order correct, change the line to foreach (sort($sizes, SORT_NUMERIC) as $size => $tmp){

jancha Over a year ago

added sorting to code. p.s. you have to use ksort in my case, as sizes are keys.

OpenGG · Accepted Answer · 2011-10-04 14:31:29Z

1

Use a temporary array to store the numbers that have been echoed then.

answered Oct 4, 2011 at 14:31

OpenGG

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Comments

Sjoerd · Accepted Answer · 2011-10-04 14:33:03Z

1

Make a new array with just the first value

$diameter = array();
foreach ($tires as $tire) {
    $diameter[] = $tire[0];
}

Then, use array_unique() to remove the duplicates, or only add them to $diameter if they are not already in there.

Then use that $diameter array to create the dropdown.

This has the advantage that you can also sort the $diameter array.

answered Oct 4, 2011 at 14:33

Sjoerd

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