Javascript using the ceiling function for value less than 1

Question

So, I have a list of items and I want to check how many pages I would need if I want to show , say, 10 items per page

ie

220 should give me 22 pages

134 should give me 14 pages

I am using the ceiling function to get the number of pages

var pages = parseInt(items)/10;
alert("pages " +pages);
alert(Math.ceil(pages));

The problem which I am having is if I have 7 items, I am expecting it to give me 1 page. However, I don't get any output. I have noticed that I only get an output if the value for pages from

var pages = parseInt(items)/10;

is greater than 1 , How do I fix this problem?

I just tried your code in Chrome's console with `items = 7` and it works fine - I get a second output of `1`. Can you replicate your problem in a [JSBin](http://jsbin.com)? — Bojangles, Oct 18 '13 at 22:41
Is `items` really a number? Try passing the radix parameter. — elclanrs, Oct 18 '13 at 22:41
Chrome, Firefox, doesn't matter - I tried the same code in Firebug and I still get `1` — Bojangles, Oct 18 '13 at 22:42
We need a demo to reproduce the issue, it seems to work fine. — elclanrs, Oct 18 '13 at 22:47
What does "I don't get any output" mean? Does the alert still *show*? Also, use `parseInt(items, 10)` just to make sure there is no radix fun going on. — user2864740, Oct 18 '13 at 22:48
@Bojangles I have just replicated my code in jsbin and I get 1 but not when I run it in firefox — littledevils326, Oct 18 '13 at 22:50
Then you need to show more code - `items` may not be what you think it is, or something else will be changing your output — Bojangles, Oct 18 '13 at 22:51

score 0 · Answer 1 · answered Oct 19 '13 at 00:14

I think your problem lies elsewhere. Consider the following Math.ceil operations:

> Math.ceil(220/10)
22
> Math.ceil(134/10)
14
> Math.ceil(7/10)
1

Then look at the operation that you might have handled -- a string version of a number:

> Math.ceil(parseInt("7")/10);
1
> Math.ceil(parseInt(" 7")/10);
1
> Math.ceil(parseInt(" 7 ")/10);
1

It would appear that Math.ceil is providing 1 as expected, unless your value of 7 is malformed.

Javascript using the ceiling function for value less than 1

1 Answers1