Javascript array argument doesn't work

Question

I had a javascript code to generate values for a table in HTML after sorting the values. At first I manually entered the array of values at the start of the javascript code. It was like: names=[tom,jerry,mickey,mouse]; grades=[10,20,30,40]; then sort them and write values in table. It worked perfect.

grades=[10,20,30,40];
var swapped;
        do {
            swapped = false;
            for (var i=0; i < grades.length-1; i++) {
                if (grades[i] > grades[i+1]) {
                    var temp = grades[i];
                    grades[i] = grades[i+1];
                    grades[i+1] = temp;
                    swapped = true;
                }
            }
        } while (swapped);
    for(j=0;j<grades.length-1;j++)
    myTable.rows[j].cells[1].innerHTML = grades[i-1];
    }

But now I have to convert it to a function. I tried like this:

function table(names,grades){
var swapped;
    do {
        swapped = false;
        for (var i=0; i < grades.length-1; i++) {
            if (grades[i] > grades[i+1]) {
                var temp = grades[i];
                grades[i] = grades[i+1];
                grades[i+1] = temp;
                swapped = true;
            }
        }
    } while (swapped);
for(j=0;j<grades.length-1;j++)
myTable.rows[j].cells[1].innerHTML = grades[i-1];
}

But it does not work. I tried calling it like:

table([tom,jerry,mickey,mouse],[10,20,30,40]);

But it doesn't work. The table is empty. What is the problem?

Thanks.

I haven't seen a do..while loop in ages. Your question brings back memories of my repeat..until days of Pascal... psst! any error messages / can you provide a jsfiddle.net ? — Glareo Pensy
– Glareo Pensy, Commented Feb 12, 2014 at 2:22
The bottom part is working good, so dont mind the sorting and writing the table part. The only problem is that when i manually writed the array at the start, it worked but now even though i call the function with same array, it dont. — yigitserin
– yigitserin, Commented Feb 12, 2014 at 2:39
@user3179249: Could you please edit your post and show us how exactly you are calling the function (from where? when?). Maybe also create a jsfiddle.net that demonstrates the problem. — Bergi
– Bergi, Commented Feb 12, 2014 at 2:57

Bergi · Accepted Answer · 2014-02-12 02:49:51Z

1

Table is empty. What is the problem?

We don't know, especially as you just said "that part was working good".

The problem is that even after calling the function like this, arrays dont have the same value as before.

Sure, you have swapped the values in them :-) If you do not want to modify the originally passed arrays, you will have to copy them before. You can use the slice method for this:

function table(names,grades,table){
    var swapped;
    names = names.slice();
    grades = grades.slice();
    do {
        swapped = false;
        for (var i=0; i < grades.length-1; i++) {
            if (grades[i] > grades[i+1]) {
                var temp = grades[i];
                grades[i] = grades[i+1];
                grades[i+1] = temp;
                swapped = true;
            }
        }
    } while (swapped);
    for (var j=0; j<grades.length; j++)
//       ^^^                     ^^
        table.rows[j].cells[1].innerHTML = grades[j];
//                                               ^^^
}

table(["tom","jerry","mickey","mouse"], [10,20,30,40], myTable);

Notice I also fixed the output-loop and made table an extra parameter.

edited Feb 12, 2014 at 2:49

answered Feb 12, 2014 at 2:42

Bergi

671k162 gold badges1k silver badges1.5k bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

That guy Over a year ago

I'm not going to lie, I haven't seen a do while loop in so long that the output loop seemed like a broken mess of code to me. +1 for pointing out the i issue. That was probably the actual problem.

Bergi Over a year ago

There's nothing wrong with the do-while loop here - the bubblesort is working fine :-)

That guy Over a year ago

It's working right, yes. I was just confused me for a second, I haven't seen do-while since I was just learning loops in JavaScript. It's an excellent example of how/why to use one though.

Collectives™ on Stack Overflow

Javascript array argument doesn't work

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related