assign input text value jquery

JavaScript
    $("button").click(function(){
  $("input:text").val("Glenn Quagmire");
 })   <?= $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("");
Source

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