Allow linear (continuous) type in bar charts x axis

[joanapaulaso]

Feature Proposal

Allow linear (continuous) type in vertical bar charts x axis, by which intervals would be automatically filled, so continuous ploted data can make sense. As for now, data is treated only as categorical, also I gess temporal, on the x axis.

Feature Use Case

A lot of data traditionally ploted on bar charts use continuous data type on both x and y axes... So it would be great if Chart.js had support for this kind of data. Check out "mass spectrum" plots as exemples.

[kurkle]

'category' in only the default, you are free to use other scale types.

[joanapaulaso]

scales: { x: { type: 'linear', }, y: { type: 'linear', } }

In my data, there is a gap between 285.1301 and 430.0905 (x axis). Would you be kind and tell me why isn't it filling the axis as a continuous data type, instead of reproducing the gap from the data? What I am doing wrong? Thanks in advance.

[kurkle]

I don't probably get what you are after. Area chart instead of bar?

[etimberg]

@joanapaulaso if you wanted more bars, you'd need to add the data manually. Our view has generally been not to modify the data array passed into the chart and just display it directly. Are you able to create a fiddle with what you're looking for?

Another idea would be to use an area chart but with a stepped interpolation so a value was held until the next was available.

[joanapaulaso]

Oh, I get it. I was looking for that in bar charts, @kurkle and @etimberg, because they are traditionally used to show mass spectrum data (which I work with). If I do that in Excel, i. e., and configure the x axis as a date type, it will give me exactly what I need (the chart on the left). On the right side is what I get for treating data as text or number ~ which is the same that I get with Chart.js... I'm sorry I can't reproduce any of this in fiddle. But I hope the image makes it clear. Any chance or way this can be implemented?

And here is the data used in both charts in the figure:

x	y
67.019	8
68.9983	26
69.0347	26
70.0062	8
71.0139	21
72.9932	11
79.9906	11
82.0061	64
91.019	194
92.0268	258
93.0346	20
95.0139	977
97.0294	15
106.0061	50
121.0296	54
123.0088	124
136.0166	80
151.0402	12

[etimberg]

This is close to the left picture. https://jsfiddle.net/ob0xc5u7/

[joanapaulaso]

Wonderful! That's it! Thank you so much!