Time Scale sometimes chops off last time unit

[tannerlinsley]

The lower screenshot is just a few pixels thinner than the first, which resulted in the chop.

VS

[etimberg]

That shouldn't be possible. Because then the last tick is < data end. Did you set the max property?

[tannerlinsley]

Nope. The only property set is the parser
On Sat, Apr 16, 2016 at 9:38 PM Evert Timberg notifications@github.com
wrote:

That shouldn't be possible. Because then the last tick is < data end. Did
you set the max property?

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#2277 (comment)

[tannerlinsley]

Very funky still. You can see the date's i'm pulling in, and the cut off. Maybe it's one whole tick that is getting cut off?

[etimberg]

I feel like this is a math rounding error. That leads to the last tick not showing

Edit: guessing that this is the problem
https://github.com/nnnick/Chart.js/blob/master/src/scales/scale.time.js#L261-L263

What I'm thinking happens is that the part that is passed to Math.ceil is supposed to be an integer, but is actually slightly smaller, then it won't wound far enough

[g13013]

Any new on this issue ?

[etimberg]

I know the problem but I don't know yet how to fix it. Essentially what happens is that initially the scale is in a unit like 'hours'. But then, the unit moves up to something like 'days'. When that happens, the tick is moved to the start of the new unit but the size of the scale in the underlying unit is not increased.

For instance, in the line-time-point-data.html sample file

1. Starting point is initially '5PM'
2. Shrinking the graph far enough leads to unit becoming 'days'
3. The old and new graphs are still exactly 5 days wide, but that's the problem. The new graph is actually larger because the first tick was rounded to the start of the day and the last tick was rounded to the end of the day. So we need to up the width in scale units by that differential amount

[g13013]

Thank you @etimberg for your quick answer

I temporarily fixed the problem by adding some entries with 0 value to the dataset, for 'day' unit I had to add 7 entries, and for the 'week' unit 1. I hope this will help.