title: Setting data used by a line graph using EPPlus
body: <p>I am trying to add a simple line graph in excel automatically by using EPPlus. I have and know the range of cells that contain the data that I want to use. I want the graph to look like the following:</p>
  
  <p><img src="https://i.stack.imgur.com/ywkVW.png" alt="enter image description here"></p>
  
  <p>The <code>Before</code> and <code>After</code> columns go on for a lot more than what is shown.</p>
  
  <p>I am using this code to create the graph and position it, but I am not sure how to set the data that the graph uses:</p>
  
  <pre><code>ExcelChart ec = ws.Drawings.AddChart("Line Time Graph", OfficeOpenXml.Drawing.Chart.eChartType.Line);
  ec.Title.Text = "Benchmarks";
  ec.SetPosition(_times.Count + 2, 0, 1, 0);
  </code></pre>
  
  <p>It might have something to do with <code>ec.Series.Add</code> but I am not sure how to properly use it. If you could point me in the right direction that would be great.</p>