title: Javascript pushing into array issue with parsing data from an object
body: <p>I am currently working on a project what requires me to use the US Census Bureau API. I have most of my code working on my portion of the project however, I am having a small issue that I do not understand. What I am trying to do is take a 113 objects, parse one property from each of those objects, and then place that property, all 113, into an array. Like I said, I almost have my code working. Below is what does work:</p>
  
  <pre><code>   for (var i = 0; i &lt;= response.features.length; i++){
        var dataPoint = response.features[i].properties.B19013_001E;
        console.log(dataPoint);
     }
  </code></pre>
  
  <p>The above code will print out all 113 points that I need to the console. (For those that are curious, the B19013_001E is median household income and that is the data that I want for basically a 113 different 'areas' within a county.)
  Now, the code does what I want but now when I make the array portion:</p>
  
  <pre><code>   var dataArray = [];
  
     for (var i = 0; i &lt;= response.features.length; i++){
        var dataPoint = response.features[i].properties.B19013_001E;
        dataArray.push(dataPoint);
     }
  
     console.log(dataArray);
  </code></pre>
  
  <p>When I console log my array, I only get this error message: 
  play.js:93 Uncaught TypeError: Cannot read property 'properties' of undefined</p>
  
  <p>What I don't understand is how come I can get all 113 points that I need individually to the console but I have an issue when I am putting them into the array? One thing that I thought of was that maybe one of the points is not present? But when I look at the console logging of 113 points I get nothing as null or undefined. Any help will be great and thank you!</p>