title: Multi-layered comparison histogram
body: <p>I need to build a histogram using the d3.js library. The histogram should look like the one below. The main objective of this histogram is to compare two sets of results. The results that are shown in the diagram below represent data gathered over the same days of the month, but in two different months (say 1st - 6th of January (green) and February (blue)).</p>
  
  <p>The histogram that I currently have basically shows the correct data, just that it does not overlay them (or even show them side-by-side). Instead it shows them ordered by the date, the results representing January first (to the left), and the ones representing February second (to the right). What should I do in order to have them show side-by-side?</p>
  
  <p>Edit: I work in an Angular environment, and I use a prebuilt directive for showing the graph. The code for the directive is lcoated at <a href="https://github.com/fullscale/dangle/blob/master/dist/dangle.datehisto.js" rel="nofollow noreferrer">https://github.com/fullscale/dangle/blob/master/dist/dangle.datehisto.js</a></p>
  
  <p>Desired result:</p>
  
  <p><img src="https://i.stack.imgur.com/QE1Zh.png" alt="desired chart"></p>
  
  <p>Current result:</p>
  
  <p><img src="https://i.stack.imgur.com/fvXxi.png" alt="current chart"></p>