put a value using jquery code example
Example: assign input text value jquery
<?= $this->Form->input('number_six', array(
'label' => false,
'class' => 'form-control number_six',
'maxlength' => "1" ,
'oninput' => "this.value=this.value.replace(/[^0-9]/g,'');"
));?>
$(".number_six").val("");