Question

I want to sum all floats in an array

when I do this in the chrome console

$("tr.project_hours").find("td.number").map(function(i,v)
{return parseFloat($(v).attr("data-time"))
})

I get

[0, 0, 0, 0, 0, 0, 0]

This is what I want

But, in my code I have more $(“tr.project_hours”) and I want to sum them separately.
So, I do

$("tr.project_hours").each(function(){
    row = $(this).find('td.total')
    row.html(sumInputsIn($(this).find("td.number").map(function(i,v){
     return parseFloat($(v).attr("data-time"))})));
    })

(‘td.total’) is the column where the result should be displayed. The problem is that the last code returns this in the console

[0, 0, 0, 0, 0, 0, 0, prevObject: jQuery.fn.jQuery.init[7], context: <tr>]

So the result is the notorious NaN.

Why do I get the prevObject in my array? And how can I refactor to get rid of it?

Answer 1

This should carry out the expected result:

$("tr.project_hours").each(function(index, element) {
    var row = $(this).find('td.total');
    var total = 0;
    $(this).find("td.number").each(function (index, element) {
        total += parseFloat($(v).attr("data-time"));
    });
    row.html(total);
});

jQuery map performs for (item in array) which apparently does not filter by hasOwnProperty() if you are getting those keys. In this case you need to write the logic yourself I guess.