PHP CREATEFROMFORMAT Día de la semana
<?php
$date = DateTime::createFromFormat('Y-m-d', '2018-06-21');
echo $date->format('l'); # l for full week day name
?>
Matteoweb
<?php
$date = DateTime::createFromFormat('Y-m-d', '2018-06-21');
echo $date->format('l'); # l for full week day name
?>