function validate()
{
    if (!isNaturalNumber(document.form1.p, "for the Principal amount"))
    {
        return false;
    }

    if (!isValueInRange(document.form1.r, 1, 100, "for the Rate of interest"))
    {
        return false;
    }

    if (document.form1.freq.options[document.form1.freq.selectedIndex].value == "All")
    {
        alert('Installment Frequency must be selected');
        document.form1.freq.focus();
        return false;
    }

    if (!isValueInRange(document.form1.y, 1, 100, "for the Number of year"))
    {
        return false;
    }

    return true;
}

function calc()
{
    var p = document.form1.p.value;
    var r = document.form1.r.value / 100;
    var y = document.form1.y.value;
    var div;
    var s = document.form1.freq.options[document.form1.freq.selectedIndex].value;
    var roi = r / 12;
    t1 = 12 * y;
    document.form1.n.value = round(t1, 0);
    e1 = Math.pow((roi * s + 1), t1 / s);
    e2 = (Math.pow((1 + roi * s), t1 / s) - 1) * 12;
    emi = p * r * (e1 / e2);
    document.form1.emi.value = round(emi, 0);
}

function clean()
{
    document.form1.p.value = "";
    document.form1.r.value = "";
    document.form1.y.value = "";
    document.form1.n.value = "";
    document.form1.emi.value = "";
    document.form1.freq.value = "All";
}