While generating a track with the help of dygraph library, I have set the legend: always (this display the legend with series name present on that particular track even without mouseover). But when I move to certain graph, the legend changes and shows the value of each series at that particular mouse pointer. I don't want the legend to change and it should just show the series name and not the values. I am using javascript to implement my app. Any way to do the same?
One trick that might be good enough is to supply a custom valueFormatter function for each axis which simply returns an empty string:
axes: {x: {valueFormatter: function (x) {return ''}},
y: {valueFormatter: function (y) {return ''}},
y2: {valueFormatter: function (y2) {return ''}}
}
This prevents the values from being shown, but still switches between line samples and ':' characters depending on the position of the mouse.
At the moment there's no easy way to do this. Your best bets are to either generate the legend yourself using dygraphs' API or to throw a transparent div over your chart which captures all the mouse events.
Well! it might be not a good way but I have found an alternative to do it. Declared a new boolean variable in dygraph.js which checks whether user wish to see x-y values on legend. Using this variable in function generateLegendHTML (defined in legend.js), i have made the control to always go in the first if loop. This makes the dygraph to always show static legend.
You can do the following -
Step 0 - Add a few necessary options and tags -
labelsDiv: document.getElementById("labels"),// in the dygraph options
<div id="labels"></div> <!-- Add this somewhere in your HTML-->
Step 1 - Declare a variable -
var defaultLabelHTML = undefined;
Step 2 - Use drawCallback option -
drawCallback: function(dygraph, is_initial){
if (is_initial)
{
defaultLabelHTML = document.getElementById("labels").innerHTML;
}
},
Step 3 - Use highlightCallback option -
function(e, x, pts, row)
{
document.getElementById("labels").innerHTML = defaultLabelHTML;
}
Related
I'm working with chart.js v2 and I am trying simulate the hover state of a segment on a doughnut graph when the chart loads so it appears there is a section alright highlighted.
I've been searching and combing the code for a day now and can't figure out a good way to do this.
Thanks in advance!
Setting a segment's hover style is a bit confusing because its not really documented anywhere. Nevertheless, I was able to figure it out a while back when I wanted to highlight a segment when it's legend label was hovered.
To do this, you need to use the pie chart .updateHoverStyle() prototype method and pass in the segment you want highlighted. The chart segments are stored in the _meta object in an array where each segment index matches the position of each value in your chart's data array.
Here is an example (assuming your chart instance is stored in a var called myPie.
// get the segment we want to highlight
var activeSegment = myPie.data.datasets[0]._meta[0].data[segmentIndexToHihlight];
// update the hover style
myPie.updateHoverStyle([activeSegment], null, true);
// render so we can see it
myPie.render();
You just need to define what segment you want to highlight and store it in a var called segmentIndexToHihlight and it should work.
Here is a codepen example demonstrating this. Note, I purposely did not highlight the segment on load (I wait 3 seconds) so that you can see the change occur.
I found another way to preselect a segment, basically you can simulate a click event on the point. You can find in the dataset model the position x and y. Here you can find my solution:
function simulateClick(x, y) {
const clickEvent = document.createEvent('MouseEvents');
clickEvent.initMouseEvent('click', true, true, window, 0, 0, 0, x, y,
false, false, false, false, 0, null);
document.elementFromPoint(x, y).dispatchEvent(clickEvent);
}
function initActivePoint(index) {
const activePoint = myChart.data.datasets[0]._meta[0].data[index];
simulateClick(activePoint._model.x, activePoint._model.y);
}
initActivePoint(0);
I will try to explain my problem as much accurate as possible. I am looking for a javascript chart library filling the two following conditions:
From an ajax request retrieving time series,
display dynamically data when changing the time window.
such as it is perfectly done on highstocks: http://www.highcharts.com/stock/demo/basic-line
And
plot an horizontal line corresponding to the mean,
changing when the user update the time window on the chart.
Actually it is possible to display an horizontal line. But they are fixed on the whole data and do not change accordingly when the time window is modified:
http://www.highcharts.com/stock/demo/yaxis-plotlines
I am quite new to the topic and would like to know if it'sp ossible to modify Highstock classes to have such a result. Or maybe some other js libraries exists?
Using a combination of the answer here:
Highchart, get total of visible series data after setExtremes
And an example of dynamic average using all visible series that I made for a previous question, here:
http://jsfiddle.net/jlbriggs/gweuLegq/
I put together this example, using the afterSetExtremes event, like this:
xAxis : {
events:{
afterSetExtremes:function() {
var ext = this.getExtremes();
getAverage(this.chart, ext.min, ext.max, show, width, avgColor, dashStyle);
}
}
},
Working example here:
http://jsfiddle.net/jlbriggs/c93543yL/
The idea is:
1) capture the afterSetExtremes event
2) get the resulting axis min and max
3) loop through the series data
4) if a point is between the min and max, increment the count, and add the
point's y value to the sum
5) calculate the average accordingly, check for existence of average series, if exists, update, if not, add
It could as easily use a plot line that you add/remove as needed instead of a series, but I like having it as a series so that it has a legend entry.
chart.xAxis.tickFormat(function(d) {
...
}
Is it possible to get array of "d" variables which will be passed to this callbacks before it even executed? I need to analyze this array first to know which values to show on chart and which I should hide.
Or maybe I could correct this array and pass it to tickValues.
NVD3 doesn't expose the D3 method for getting tick values from a scale/axis, but overwrites it with its own method that doesn't set the tick values...
From the source code, it looks like you should be able to get the tick values that are set automatically with
chart.xAxis.scale()
.ticks(Math.abs(chart.xAxis.scale().range()[1] - chart.xAxis.scale().range()[0]) / 100)
Note that this will only work for horizontal axes (i.e. x axes like in your case).
I have a scatter series with two points that have the same coordinates. Each point has different data associated with it (for example weight and height of different people - two different people can have exactly the same height and weight):
series: [ {
data: [{x:193.5, y:80.7, name:'danny'},
{x:193.7, y:90.7, name:'oren'},
{x:193.7, y:90.7, name:'josef'},
{x:195.5, y:80.3, name:'thomas'}]
}]
Full example at jsfiddle.
When viewing the tooltips of the chart, the tooltip of the second point shows:
Oren: 193.7,90.7
Making the data of josef inaccessible.
I would like to make the data of both josef and oren accessible, for example by putting them inside of the same tooltip.
Oren: 193.7,90.7
Josef: 193.7,90.7
How would you achieve this effect?
assume a very large data set - iteration over the entire series each time is not an option.
You could use the Tooltip formatter ( http://api.highcharts.com/highcharts#tooltip ) to manually format your tooltips.
In the formatter compare x and y value of all other points in the series(this.series) If the values are the same, add the name of these points to the tooltip.
Possible duplicate question to Bar chart in Javascript: stacked bars + grouped bars
I'm trying to create a stacked bar chart that lets you compare 2 values (dark and mid blue) to last week's data points (the secondary light blues 'behind').
Starting with multiBarChart() with .stacked(true) first I tried merging both weeks into a single array of 14 bars, where the x position could help group the bars. I tried to form my combined array of objects where .x properties' values are 0, 0.3, 1, 1.3, 2, 2.3, etc.
Unfortunately unlike lineChart() it doesn't use the x value for positioning.
Another idea is to exploit the group .stacked(false), providing 4 items (instead of 2) with the same x value. These then appear overlaid on top of each other instead of stacked.
Here the spacing looks good, but how do I stack these 2 by 2?
Hey I just developed grouped+stacked bar chart on d3.js. It is not NVD3 but it may help you.
Source
Demo
Let me just say up front that I am SO not an nvd3 expert. I'm barely past the getting-started stage myself.
That said, it looks like you're making this too hard on yourself.
I think you really want to send nvd3 two sets of data, with the x's matching between the two. (E.g., (1,y1a) corresponding to (1,y2a), then (2,y2a) with (2,y2b), etc.)
You can see this more clearly by the following:
Head to their Live Code page
Select the Group/Stacked Bar Chart.
Select the Data (JSON) tab.
Replace the first function with the following, and observe the resulting x values.:
function() {
return stream_layers(2,10,.1).map(function(data, i) {
alert( 'Stream '+i+': '+JSON.stringify(data));
return {
key: 'Stream' + i,
values: data
};
});
}
Best as I understand it, that's the model you're looking for.