Highcharts - Stack Graph Display Average of all values - highcharts

Question

I am using highcharts for statistical data displaying. I want to display , on the stack label , the average of all the values .
Below is what i am doing but i cant seem to get it right :
yAxis: {
min: 0,
title: {
text: 'Task'
},
stackLabels: {
style: {
color: 'black'
},
enabled: true,
formatter: function() {
return (this.axis.series[1].yData[this.x]).toPrecision(2) + '%';
}
}
},
The above only takes the last value on the stack and shows the percentage. For instance , if the last value is 50 , the above displays 50% as the stack value . I want to take an average of all the values. Any help would be appreciated.

Answer 1

If you want to show any stack's percentage mean if your stacked column has two stack A-5 and B-10 , then the % of B in column is 66% and % of A is 33%. If you want to show that use following in formatter function ( refer This Fiddle Link)
formatter: function() {
return (this.axis.series[1].yData[this.x] / this.total * 100).toPrecision(2) + '%';
}
Updating as per OP 's comment Refer Working fiddle here
Use following code : Make your data in a variable and calculate the sum
var seriesData = [{
name: 'Incomplete',
data: [1, 3, 4, 7, 20]
}, {
name: 'Complete',
data: [3, 4, 4, 2, 5]
}];
var total = 0;
$.each(seriesData,function(item){
$.each(seriesData[item].data,function() {
total += this;
});
});
And then use following in stacklabel formatter :
formatter: function() {
return ( this.total/ total * 100).toPrecision(2) + '%';
}
series:seriesData
hope it helps :)

Answer 2

This doesn't seem to be as easy as it should be.
I would accomplish this by pre-processing the data to generate an array of averages, and then referencing that array from the stackLabels formatter function.
Example, build the averages (assumes array 'data' with sub array for each series data values):
var sum = 0;
var averages = [];
var dataLen = data.length;
$.each(data[0], function(x, point) {
sum = 0;
for(var i = 0; i < dataLen; i++) {
sum += data[i][x];
}
averages.push(sum/dataLen);
})
And then in the formatter:
yAxis : {
stackLabels: {
enabled: true,
formatter: function() {
return Highcharts.numberFormat(averages[this.x],2);
}
}
}
Example:
http://jsfiddle.net/jlbriggs/vatdrecb/
If I could find a way to get a reliable count of the points in each stack, you could just use
return this.total/countOfPoints;
in the formatter without needing to build an array, but I can't seem to reliably get that count.