Issue in Displaying NaN values


I created a function and I encountered problem because I got a NaN values. And I want to resolve it…I don’t want to display NaN values. instead of NaN I just want it blank.

here is my code:

function doz(oText){
    var P27_max = document.getElementById("P27_max").value;
    var P27_max_convert = parseFloat(P27_max) + parseFloat(1);
    var P27_maxdoz = document.getElementById("P27_maxdoz").value = P27_max_convert;

    var P28_max = document.getElementById("P28_max").value;
    var P28_max_convert = parseFloat(P28_max) + parseFloat(2);
    var P28_maxdoz = document.getElementById("P28_maxdoz").value = P28_max_convert;

when I entered data in
P27_max so the P27_maxdoz was computed but the problem is the P28_max has also value ‘NaN’.

How can I eliminate or did not display NaN

Thank you

Give the following a try, i simplified the process of how it collects and stores the value as well as a check to see whether the conversion leads to a number otherwise it adds a blank value.

function doz(oText) {
    var value, convert, self,
        collect = {
            ['P27_max', 'P27_maxdoz', 1],
            ['P28_max', 'P28_maxdoz', 2]

    for (var i = 0, max = collect.length; i < max; i++) {
        // Caching
        self = collect[i];

        value           = document.getElementById(self[0]).value;
        convert         = parseFloat(value) + self[2];
        window[self[2]] = document.getElementById(self[1]).value = (!isNaN(convert) ? convert : '');

I resolved it using this code:

    var P45_min = document.getElementById("P45_min").value;
    var P45_min_convert = parseFloat(P45_min) + parseFloat(13);
    if( !isNaN(P45_min_convert) ){
    var P45_mindoz = document.getElementById("P45_mindoz").value = P45_min_convert;

Thank you