SaltyCrane Blog — Notes on Python and web development on Ubuntu Linux

jQuery flot stacked bar chart example

Flot is a Javascript plotting library for jQuery. Here are my steps to create a simplified version of the stacked bar chart example from the flot examples page. For more information, see the API documentation.

  • Download and unpack:
    cd ~/src/jquery/flot_examples
    curl | tar xzf -
  • ~/src/jquery/flot_examples/stacked_bar_ex.html:
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "">
      <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
      <!--[if IE]><script language="javascript" type="text/javascript" src="flot/excanvas.min.js"></script><![endif]--> 
      <script type="text/javascript" src=""></script>
      <script type="text/javascript" src="flot/jquery.flot.js"></script>
      <script type="text/javascript" src="flot/jquery.flot.stack.js"></script>
      <title>Flot stacked bar example</title>
      <div id="placeholder" style="width:550px;height:200px;"></div>
      <script type="text/javascript" src="stacked_bar_ex.js"></script>
  • ~/src/jquery/flot_examples/stacked_bar_ex.js:
    $(function () {
        var css_id = "#placeholder";
        var data = [
            {label: 'foo', data: [[1,300], [2,300], [3,300], [4,300], [5,300]]},
            {label: 'bar', data: [[1,800], [2,600], [3,400], [4,200], [5,0]]},
            {label: 'baz', data: [[1,100], [2,200], [3,300], [4,400], [5,500]]},
        var options = {
            series: {stack: 0,
                     lines: {show: false, steps: false },
                     bars: {show: true, barWidth: 0.9, align: 'center',},},
            xaxis: {ticks: [[1,'One'], [2,'Two'], [3,'Three'], [4,'Four'], [5,'Five']]},
        $.plot($(css_id), data, options);
  • View ~/src/jquery/flot_examples/stacked_bar_ex.html in the browser:


#1 Colin Wren commented on :

Excellent Post!

I've just today been looking at Flot to create some charts for work and this really helped me grasp how to create a stack chart with custom labels on the x-axis.

Thanks so much

#2 Miloš Rašić commented on :

See how the plugin paints a blue line on the number far bar where he value for "bar" is 0? I'd call this undesirable behavior, or at least I wouldn't desire it in my graphs. Is there any way to fix this?

#3 Harpreet commented on :

yes you can hide the bar having zero by setting its x-axis data to null, in above case javascript code would be data[1].data[4][0]=null

#4 suresh commented on :

this example is very useful for us and understanding is easy by this.

#5 Joshua Lay commented on :

Thanks for this post. I found the examples in the package annoying as they displayed example graphs but without the code written out nicely to generate it.

#6 robert commented on :

Do you see how the colors in the legend go from top to bottom, whereas they stack on the graph from bottom to top? Is there any way to make the colors appear inverted in the legend so they match the visual order of the graph?

#7 phatneglo commented on :

thank you for keeping nice and simple

#8 Matt commented on :

Awesome! Great tutorial. One question, is there away to control the position of the legend? Mine is aligned to the left edge of the graph and is extending the entire width of the graph. I'd like to position it outside of the graph, just to the right of it

#9 Vipin commented on :

how do u set the steps/intervels for the axis like for the X axis i want the number 0,1,2... and for Y axis i want 0,5,10,15,...

also can i rotate the labled in the Y axis for eg: One, Two.... can i rotate them by 90 degree...

#10 Casey Wise commented on :

Stacks of thanks for posting and helping to destroy my flot learning curve! I needed to come up quick and working from examples is how I learn. You get a gold star.

#11 sean_rainey commented on :

Hi thanks for your help. But do you know how to do this without stacking? Thanks.

#12 Lewis commented on :

How to set input in array? Axis Y : 1,23,42,45 Axis X : 1 to 10

#13 madia commented on :

works like charm! thanks!

#14 Farooq commented on :

thanks! it help me a lot.

#15 Francois commented on :

To answer to two of the questions:

  • to change color just add item'color' : [your color] in the array data like

    var data = [ {label: 'foo', data: [[1,300], [2,300], [3,300], [4,300], [5,300]], color: 'red'}, {label: 'bar', data: [[1,800], [2,600], [3,400], [4,200], [5,0]], color: "rgba(255, 0, 0, 1)"}, {label: 'baz', data: [[1,100], [2,200], [3,300], [4,400], [5,500]], color: orange}, ];

  • to have the legend outside the graph just create another graph, the same in a div next to the graph div but with all option at false except the legend like:

//the option with legend set to false var options = { series: {stack: 0, lines: {show: false, steps: false }, bars: {show: true, barWidth: 0.9, align: 'center',},}, legend: { show: false }, xaxis: {ticks: [[1,'One'], [2,'Two'], [3,'Three'], [4,'Four'], [5,'Five']]}, };

//your true graph without legend $.plot($(css_id), data, options);

//the option with only legend
var options = { series: {stack: 0, lines: {show: false, steps: false }, bars: {show: false, barWidth: 0.9, align: 'center',},}, legend: { show: true, position: "ne", backgroundOpacity: 0.2 }, xaxis: { show: false}, yaxis: { show: false} };

//the graph with only the legend placed in the div you want (id=place+"Leg") $.plot($(css_id), data, options);

Then you control the position and the size of your legend outside the true graph with its div. Regards Francois