toggleclass if more than 0

How to add a class if the number is greater than 0

$( document ).ready() 
   var points = parseFloat($('.main_price > .autocalc'));
if(autocalc > 0) {
    $('.buy').toggleClass('orange');
} else {
    return false;
}
   }

<h2 class="main_price"><span class="autocalc">259 c.</span></h2>
<div class="buy">BUY</div>