title: PHP - Get Array value by Index instead of Key
body: <p><br>
  I've got a multidimensional array returned by an API call. The values into this array are stored with a key like this : </p>
  
  <pre><code>Array(["BTC_XRP"] =&gt; 1)
  </code></pre>
  
  <p>I can get the values of the Array by getting them using the keys (like BTC_XRP), but what if I need to get the value using the Index?<br>
  For example, how do I get each value of the Array using a for loop if I can't get the values by the Index?<br>
  Since the Array is composed by something like 100 values, I need to echo every one using a for loop, but this gives me this error : </p>
  
  <blockquote>
    <p>Notice: Undefined offset: 0</p>
  </blockquote>
  
  <p>Is it possible to get to a value using the Index instead of the Key?<br>
  Furthermore, I'd like to get the Key by the Index. If I want to get the Key of the first value, I'd like to get it using the 0 Index.<br>
  Thanks!</p>