title: How to read sizes of packed files inside zip archive using R
body: <p>The following code in R returns a data frame which includes filenames, unpacked length in bytes and the date (without extracting the files).  </p>
  
  <pre><code>unzip(path_to_zip, list  = T)
  </code></pre>
  
  <p>I am wondering how I can also extract the size of the packed (compressed) files or alternatively the compression ratio for each file. </p>
  
  <p>I am using Windows 7 machine.</p>
  
  <p>Thanks!</p>