Develop Reference

Is it possible to avoid the shrinking of Chart.js pie charts when accompanied by labels?

To get labels on Chart.js Pie and Doughnut charts, there are plugins to do so, like: chartjs-plugin-labels but after doing so I noticed a big problem for my UI design:
The size of the actual chart shrinks so that the labels fit within the canvas. It makes sense that the labels need to be able to fit within the canvas they're rendered on, and thus the shrinking of the chart. But sometimes I may use labels, and other times not, and I need my pie charts to render the same size regardless.
Is there a solution in the settings of either Chart.js (the label plugin I'm using is compatible with < 3.0, I'm using 2.9) or chartjs-plugin-labels to maintain consistent chart size, regardless of whether labels are applied?
I tried applying an empty label to every chart, but the size of the chart actually shrinks based on the specific size of the labels being rendered, so aside from being a hacky solution, it doesn't consistently solve the uniformity problem.
For example maybe a way to make charts start off taking 50% of the canvas?

Yes, this is fairly simple actually. The chartjs-plugin-labels.js file contains several lines which force the chart to become smaller when the label settings set the position to either "border" or "outside". Download the script to your own server, comment out the lines below, and everything should work as expected. CodePen demo
Comment/remove these lines:
if (this.options.position === 'border') {
offset = (lines.length - 1) * this.options.fontSize / 2;
}
if (label.options.position === 'outside') {
someOutside = true;
var padding = label.options.fontSize * 1.5 + label.options.outsidePadding;
if (padding > maxPadding) {
maxPadding = padding;
}
}
Here is the updated JS file you can use: https://pastebin.com/raw/gSffqqKu
Just download it as chartjs-plugin-labels.js and use it in your project instead of the original plugin file.

How to properly add padding to the plot area in a D3 line chart?

I have a line chart in D3 as seen here:
I am attempting to extend the x-axis to be the same size as the y-axis tick width. Currently I am setting the ranges as follows:
// set the ranges
var x = d3.scaleTime().range([20, width - 20]);
var y = d3.scaleLinear().range([height, 0]);
This achieves my desired effect of pushing the plot in from the left and right sides but does not extend the x-axis. I'm sure there has to be a way to add padding to the plot without changing the ranges but I can't seem to figure out how?

There's no easy way to add padding to a linear scale.
However, in your case, since your x axis is presenting categorical data (days of the week), you can use a d3.scalePoint and configure its outer padding with the padding function.

Chart.js horizontal line chart or modified horizontal bar chart

I am using chart.js to try to create a timeline of events relative to current date.
The horizontal bar chart is close but would like to show only the tips of the bars eg as points which would pretty much be a horizontal line chart.
I have shown my horizontal bar chart along with a mock-up of what it would look like as horizontal line chart.
Is this possible with chart.js ?

You first need to know that every information that you can edit about the chart is stored in the variable containing your chart (called myChart usually, but my2Bar in your fiddle).
If you want to globally change the graph, you will need to edit attributes in myChart.config.options.
If you want to change a specific chart, you will need to edit attributes in myChart.config.data.
In this case, you need to change a specific chart (which is the horizontal bar).
If you happen to check the logs of your graph, and go very deep in the config, you will finally see that bars in your chart are drawn using attributes stored in myChart.config.data.datasets[0]._meta[0].data[n]._model (n being the nth rectangle drawn, top to bottom).
Some attributes you can find there :
base : The X position where the rectangle is starting to be drawn (0 in your xAxe for instance).
x : The rectangle is being drawn until this X position.
height : The height of the drawn rectangle.
and so on ...
To edit these values, you just need to loop in your different rectangles (the n in the above path).
But you just can't do it manually on the config of your variable. If you do this, it won't work since your chart is responsive (on resize, it will redraw the chart using the former options).
What you must use are Chart.js plugins.
Plugins let you handle all the events that are triggered while creating, updating, rendering your graph.
Then, in your beforeRender event (triggered after the initialisation, but before the drawing), you need to loop in your different rectangles to edit the values to affect how they will be drawn :
beforeRender: function(chart) {
for (var i = 0; i < chart.config.data.datasets[0]._meta[0].data.length; i++) {
// Change both `3` values to change the height & width of the point
chart.config.data.datasets[0]._meta[0].data[i]._model["base"] = chart.config.data.datasets[0]._meta[0].data[i]._model["x"] + 3;
chart.config.data.datasets[0]._meta[0].data[i]._model["height"] = 3;
}
}
Here is a jsFiddle with the final result.
Unfortunately, I wasn't able to make round dots, instead of squared ones.
Update :
I have also made another jsFiddle where all the dots are linked together which makes it look like it is a horizontal line chart (can be improved of course, but it is a good start).

Highcharts SetExtremes Sourcewidth and height

I have a highcharts column chart(http://www.highcharts.com/docs/chart-and-series-types/column-chart) with almost morethan 13000 categories on x-axis i.e. i am using datehour axis and i have a bar at specific datehour. Let say i have to take pdf containing all the data, Is it possible? If so can i put extremes max value to 13000.
What is the max value that Highcharts support in case of SetExtremes, Source width and SourceHeight?
I can not fine these values on Highcharts website.
Thanks.

gRaphael line chart shade changes

I'm currently implementing a line chart in gRaphael which requires the x axis to move up the y-axis such that it lies on zero (which I have already accomplished by drawing my own axes).
However, I'm now encountering a problem when attempting to shade the area above/under the x-axis; gRaphael's shade function only shades from the bottom of the graph to Y-height (as opposed to being from 0 on the y-axis to the y-height). The result is the following:
http://i.stack.imgur.com/ZuPhw.png
I have found a couple of lines in g.line.js which look suspiciously like they would help, but I have no idea what the "L", "C", and "M" values mean (I assume they are to tell a part of the program to draw a line etc?)
Any help from anybody more informed than me would be greatly appreciated!

I solved this by overriding the g.line.js file and creating an offset to add to the Y values. The offset was calculated by considering the maximum and minimum values on the Y axis, the height of the SVG itself and the "gutter" - a value which adds padding to the SVG itself (so that values on the axes can be displayed better). The formula looks like this (and is, incidentally, identical to how the axes were moved to zero):
(height - 2*gutter)*(miny/(maxy-miny))