Wrap n number of divs into a parent div

WrapDivs.php

<?php 
$i=0;
$wrap_count = 4; // you can change this no of divs to wrap
foreach ($categories as $category) 
{ 
    $i+=1;
    if($i%$wrap_count==1)
        echo '<div class="row">';
?>
    <div class="col-lg-3 col-md-3">.....</div>
<?php 
    if($i%$wrap_count==0)
        echo '</div>';
} 

if($i%$wrap_count!=0)
    echo '</div>';
?>