title: Extract only values with a decimal point in between from strings
body: <p>I have a dataframe with strings such as:</p>
  
  <pre><code>id &lt;- c(1,2)
  x &lt;- c("...14.....5.......................395.00.........................14.........1..",
     "......114.99....................124.99................")
  df &lt;- data.frame(id,x)
  df$x &lt;- as.character(df$x)
  </code></pre>
  
  <p>How can I extract only values with a decimal point in between such as 395.00, 114.99 and 124.99 and not 14, 5, or 1 for each row, and put them in a new column separated by a comma?</p>
  
  <p>The ideal result would be:</p>
  
  <pre><code>  id            x2
    1         395.00
    2  114.99,124.99
  </code></pre>
  
  <p>The amount of periods separating the values are random.</p>