title: Merge 2 Object Array Data Series That Share the Same [0] Index
body: <p>So let's say that you have 2 series of data.  (Both object arrays, in your choice of a serialized JSON string, or the actual objects).</p>
  
  <p>For Instance:</p>
  
  <pre><code>string str1 = @"{""datapoints"":[[""02/28/2019"",146800.0],[""02/27/2019"",147700.0],[""02/26/2019"",153900.0]]}";
  </code></pre>
  
  <p>Then, you have a second series that is very similar...</p>
  
  <pre><code>string str2 = @"{""datapoints"":[[""02/28/2019"",145600.0],[""02/27/2019"",143600.0],[""02/26/2019"",152200.0]]}";
  </code></pre>
  
  <p>Note: the object arrays inside are both a length of "2", and both contain the same "date" as the [0] index.</p>
  
  <p>How does one merge the 2 object arrays into 1, to yield the following output...</p>
  
  <pre><code>string str3 = @"{""datapoints"":[[""02/28/2019"",145600.0,145600.0],[""02/27/2019"",143600.0,143600.0],[""02/26/2019"",152200.0,152200.0]]}";
  </code></pre>
  
  <p>For clarity, I'm interested in using the [0] index once, and merging the [1] indexes together.  (the number values)</p>
  
  <p>Extra credit if this can be a loop, or can be done with any number of series.</p>