WooCommerce 'Create variations from all attributes' randomisation fix

gistfile1.txt

<?php

/*
*  array_cartesian
*
*  This function will fix a frustrating issue in the WooCommerce plugin
*  When adding a product using variations, you will most likely use the 'Create variations from all attributes' function
*  The issue with this function is that it will create the variations in a random order
*  This is frustrating for your clients to edit
*
*  The solution is to add the following code to your functions.php file which will modify a function used
*  by WooCommerce which does the same functionality, but will keep the expected variation order.
*  Origional issue posted here: http://ideas.woothemes.com/forums/133476-woocommerce/suggestions/2650776-be-able-to-sort-variations-of-variable-products-in
*
*  @type	function
*  @date	25/10/2015
*  @since	n/a
*
*  @param	$input (array)
*  @return	$input (array)
*/


if ( ! function_exists( 'array_cartesian' ) ) {
	
	function array_cartesian( $input ) {
		
		// vars
		$i = 0;
		$max = 1;
		$keys = array_keys($input);
		$item = array();
		$limits = array();
		$variations = array();
		
		// populate item
		foreach( $keys as $k ) {
			
			// reset array keys
			$input[ $k ] = array_values($input[ $k ]);
			
			
			// set item value
			$item[ $k ] = $input[ $k ][0];
			
			
			// set limit default
			$limits[ $k ] = count($input[$k]);
			
			
			// increase max
			$max = $max * count($input[$k]);
			
		}
		
		
		// loop
		while( $i < $max ) {
			
			// vars
			$i++;
			$index = $i-1;
			$variation = $item;
			
			
			// calculate
			foreach( array_reverse($limits) as $k => $limit ) {
				
				// bail early if 0
				if( $index == 0 ) break;
				
				
				// vars
				$floor = floor( $index / $limit );
				
				
				// update index
				$index = $index - ($floor * $limit);
				
				
				// set $variation
				$variation[ $k ] = $input[ $k ][ $index ];
				
				
				// update index for new looping
				$index = $floor;
				
			}
			
			
			// append
			$variations[] = $variation;
			
		}
		
		
		// return
		return $variations;
		
	}
	
}

?>

Great solution, I raised a core ticket in WooCommerce for this to be integrated.. fingers crossed!

woocommerce/woocommerce#9515

Update - changed logic to a much simpler and easy to understand solution!

Hi there I am trying to get all makes and models of cars to sort automatically by alphabetically. Will this work for that issue. Currently I have to drag and drop after they are created. Where do I add the above code?

This works great except for sorting sizes with numbers above 10. I have a product with many sizes such as 1' x 3', 2' x 3', 3' x'5 ,8' x 10', 11' x 14'.

This bit of code puts 11' x 14' right after 1' x 3'. It is like it only sort by the first digit. How can I change it to put 11 at the end where it should go?