Change URL paramenters or Query Strings in JavaScript

function replaceQueryParam(param, newval, search) {
    var regex = new RegExp("([?;&])" + param + "[^&;]*[;&]?");
    var query = search.replace(regex, "$1").replace(/&$/, '');

    return (query.length > 2 ? query + "&" : "?") + (newval ? param + "=" + newval : '');
}

 var str = window.location.search
 str = replaceQueryParam('rows', 55, str)
 str = replaceQueryParam('cols', 'no', str)
 window.location = window.location.pathname + str