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Highcharts Interactivity between plots - looking for code improvements

I have a set of interconnected charts with Highcharts and callback functions. Specifically, put together a scatter plot with an x-axis range selection, which connects to a bar chart that reflects the average y-value of the points selected, by category.
It uses the 'events' key when creating the chart to call a function that edits and redraws the bar chart.
Please click on this sandbox link to see the example that I have put together: https://codesandbox.io/s/youthful-browser-mid8x?file=/index.html
I would like to know if the code can be written any better with improvements. If anyone can please review and let me know. Thanks.

You don't need to call redraw after setData:
function update_chart2(xmin, xmax) {
...
chart2.series[0].setData(new_data);
// chart2.redraw(); - redraw is called in setData
}
You can update xAxis with plot-band options instead of removing and adding it.
events: {
selection: function (event) {
...
if (event.xAxis) {
xmin = event.xAxis[0].min;
xmax = event.xAxis[0].max;
this.xAxis[0].update(
{
plotBands: [
{
from: xmin,
to: xmax
}
]
},
false
);
}
update_chart2(Math.floor(xmin) + 1, Math.floor(xmax) + 1);
},
...
}
API Reference:
https://api.highcharts.com/class-reference/Highcharts.Series#setData
https://api.highcharts.com/class-reference/Highcharts.Axis#update

dc.js: extending line and area to end of chart

I'm trying to draw an area chart using dc.js, and the end date (i.e. far right) of the chart is based on the current date, not the last date in the dataset. In cases where there's a date gap between data points, I want the area to extend from one point to the next, not draw at 0.
Given this data:
var data = [
{domain: "foo.com", project: "pdp", repo: "myrepo", commit_date: "6/1/2014", lines_added: 100, lines_deleted: 50},
{domain: "foo.com", project: "pdp", repo: "myrepo", commit_date: "7/1/2014", lines_added: 100, lines_deleted: 50}
];
var ndx = crossfilter(data);
The chart's line/area currently ends at the "7/1/2014" data point, but I want it to stretch the entire length of the chart.
The relevant code for drawing the chart is:
var dateDim = ndx.dimension(function(d) {return d.commit_date;});
var minDate = dateDim.bottom(1)[0].commit_date;
var maxDate = new Date();
var domainGroup = dateDim.group().reduceSum(function(d) {return d.cumulative_lines;});
unshippedlineChart
.width(500).height(200)
.dimension(dateDim)
.group(domainGroup)
.renderArea(true)
.x(d3.time.scale().domain([minDate,maxDate]))
.brushOn(false)
.interpolate('step-after')
.yAxisLabel("Unshipped Value");
Full example is at http://jsfiddle.net/xayhkcvn/1/

You didn't actually ask a question :-), but I think you may be looking for ways to prefilter your data so that it gets extended to today, and to remove any zeros.
This stuff isn't built into dc.js, but there is some example code in the FAQ which may help. Specifically, there is a function remove_empty_bins which adapts a group to remove any zeros.
You could similarly define a function to add a final point (untested):
function duplicate_final_bin(source_group, key) {
return {
all:function () {
var ret = Array.prototype.slice.call(source_group.all()); // copy array
if(!ret.length) return ret;
ret.push({key: key, value: ret[ret.length-1].value});
return ret;
}
};
}
You can compose this with remove_empty_bins:
var super_group = duplicate_final_bin(remove_empty_bins(domainGroup), maxDate);
The idea is to create a wrapper object which dynamically adds or remove stuff from the (always changing) source_group.all() on demand. dc.js will call group.all() whenever it is redrawing, and these wrappers intercept that call and adapt the data the crossfilter group returns.

Smooth animation for newly added data points with flot

I need to animate a real time graph with flot so that each new data point will transition smooth into the data set etc.
I've made a plunker with the basic flow:
http://plnkr.co/edit/oPahmS?p=preview
But I would like to make it more like highcharts
http://www.highcharts.com/demo/dynamic-update
Does anyone know a plugin or a way to do this with flot?

I don't believe either of the flot animation plugins provide this ability. Instead, it can be done with a little bit of jquery animate magic.
addPointAnimate = function(){
var series = somePlot.getData()[0]; // first series
var lastX = series.data[series.data.length-1][0]; // last x value
var opts = somePlot.getOptions();
opts.xaxes[0].max += 1; // adjust xaxis to make room for new point
somePlot.setupGrid();
$('#placeholder').animate( { 1:1 }, {
duration: 1000,
step: function ( now, fx ) {
series.data.push([lastX+fx.pos, Math.sin(lastX+fx.pos)]); // for each step of animation, push on an intermediate value
somePlot.setData( [series] );
somePlot.draw(); // redraw with intermediate value
}
});
return true;
}
Here's a working fiddle.

updating a line graph in d3 is not working

i am trying to update a line graph and it is not throwing any error but it is also not updating the graph.
i am deleting a point and adding a new one with an incremented rate and incremented created_at date by a second(trying to follow http://bl.ocks.org/benjchristensen/1148374)
function redrawWithoutAnimation() {
for (var i in chart_data) {
linedata = chart_data[i];
//delete first element of array
linedata.points.reverse().shift();
//create a new point
rate = linedata.points[0].rate + 1;
created_at = linedata.points[0].created_at + 6000;
new_point = {};
new_point.rate = rate;
new_point.created_at = created_at;
linedata.points.push(new_point);
console.log(linedata);
}
// static update without animation
svg.selectAll("path")
.data([linedata.points]); // set the new data
line(linedata.points); // apply the new data values
}
redrawWithoutAnimation();
setInterval(function () {
redrawWithoutAnimation();
}, 8000);
here is my code
http://jsfiddle.net/yr2Nw/8/

Working fiddle: http://jsfiddle.net/reblace/GsaGb/1
There's a few issues here...
First, you were updating all the chart_data in the for loop, but outside the loop, you were only trying to update the line still stored in the linedata variable after loop execution. You should try to avoid having variables with greater scope than they need. It can lead to bugs like this one:
svg.selectAll("path").data([linedata.points]);
line(linedata.points);
You should instead use D3's data joining to rejoin the new data to all the paths at once declaratively like so:
linesGroup.selectAll("path")
.data(chart_data)
.attr("d", function(d){ return line(d.points); });
What that code's doing is it's selecting the paths and then joining each of them to the chart_data elements and then binding the appropriate line generator to the "d" attribute for the appropriate path.
Then, you need to update your x axis and y axis otherwise the plot will just shoot off the drawn area. This code is updating the domains and then rebinding the axes to the dom elements so they redraw:
xAxis.scale().domain([
d3.min(chart_data, function (c) { return d3.min(c.points, function (v) { return v.created_at; }); }),
d3.max(chart_data, function (c) { return d3.max(c.points, function (v) { return v.created_at; }); })
]);
yAxis.scale().domain([
0,
d3.max(chart_data, function (c) { return d3.max(c.points, function (v) { return v.rate; }); })
]);
svg.select(".x.axis").call(xAxis);
svg.select(".y.axis").call(yAxis);
There were a few other bugs I fixed them in the Fiddle. For example, you need to calculate the time for the new point based on the last element in the array, not the first, otherwise the line can't interpolate properly since its no longer a continuous function... and this is a bit more concise way to do your line updates:
for (var i=0; i<chart_data.length; i++) {
linedata = chart_data[i];
//delete first element of array
var removedPoint = linedata.points.shift();
//create a new point
var lastpoint = linedata.points[linedata.points.length-1];
var new_point = {
rate: removedPoint.rate,
created_at: lastpoint.created_at + 6000
};
linedata.points.push(new_point);
}
Also note that you shouldn't use the for(var in) loop for Arrays, that's for iterating over the properties in an object.
There's still some issues, but I think this should help get you over the hurdle you were stuck on. Anyways, it looks cool in action!

Fine fenac.. You facing so many problems since your data is not in good format for your requirements..
as per http://bl.ocks.org/benjchristensen/1148374 The x-axis data must be (data[] (data array))
Your data is something like this
[objects,object,object] where each object holds one element of xaxis value.. so the pushing and shifting is not possible..
try to change the format of the data (linedata.points) to an array (data[]) and try it out sure it works..
You just need to put all the values in linedata.points into an array data[] and use this data[] to animate your line..
Since yours the multiline.. you need to create 2D array and must pass them accordingly...
Cheers..
I updated your jsfiddle
setInterval(function () {
console.log(linedata.points);
var v = linedata.points.shift(); // remove the first element of the array
linedata.points.push(v); // add a new element to the array (we're just taking the number we just shifted off the front and appending to the end)
redrawWithoutAnimation();
}, 3000);
http://jsfiddle.net/yr2Nw/9/
But still it wont works till you do that work...
Personal Suggestion: First Try with single line graph then go with looping for multiline...

Create a custom lines in EXTJS Line Chart

I need to add a vertical line and a text on my Line chart near to a specified point on chart (specified by data, not coordinates). I tried to use CompositeSprites, but it doesn't show on screen completely. I'm new to ExtJS drawing.

You should put the logic that adds the vertical line inside of the chart's refresh event listener, that way, if the data changes the line position will be updated to reflect the new data.
Here's an example of how you could do it, assuming you can get a reference to the chart container (e.g. "myPanel"):
var myChart = myPanel.down('chart'),
myChart.on('refresh', function(myChart) {
// First, get a reference to the record that you want to position your
// vertical line at. I used a "findRecord" call below but you can use
// any of the datastore query methods to locate the record based on
// some logic: findBy (returns index #), getAt, getById, query, queryBy
var myRecord = myChart.store.findRecord(/*[someField]*/, /*[someValue]*/),
// a reference to the series (line) on the chart that shows the record
mySeries = myChart.series.first(),
// get the chart point that represents the data
myPoint = Ext.each(mySeries.items, function(point) {
return myRecord.id === point.storeItem.id;
}),
// the horizontal position of the point
xCoord = point.point[0],
// check for any previously drawn vertical line
myLine = myChart.surface.items.findBy(function(item) {
item.id === 'vert'
});
// if there is no previously drawn line add it to the "surface"
if (!myLine) {
myChart.surface.add({
id: 'vert', // an id so that we can find it again later
type: 'rect',
width: 4,
height: myChart.surface.height, // the same height as the chart
fill: 'black',
opacity: 0.5, // some transparency might be good
x: xCoord,
y: 0 // start the line at the top of the chart
});
// if we already had a line just reposition it's x coordinate
} else {
myLine.setAttributes({
translate: {
x: xCoord,
y: 0
}
// I think the chart gets drawn right after the refresh event so
// this can be false, I haven't tested it though
}, false);
}
});
If you are using the MVC pattern your event handler would look a little different (you wouldn't use myChart.on()).