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copied!<p>The details of my comment above:</p> <ul> <li>Fire up a Firefox with <a href="http://getfirebug.com/" rel="nofollow noreferrer">Firebug</a> :)</li> <li>Fill in the form with one pair of desired plate no. and so, and click submit ("Determine VLF")</li> <li>Click "Net" tab in Firebug and check the sent request to the server, like (sorry, Hungarian user interface - but you will get the point I hope):</li> </ul> <p><img src="https://i.stack.imgur.com/vojNE.png" alt="enter image description here"></p> <ul> <li>You can see that a POST request was sent, but the data can be reached via a GET request also, so just right click on the "POST vlfFees.do" and choose "Copy URL with all parameters" and you are done by getting the required URL.</li> <li>You can modify the URL with desired LPN and VIN in the URL simply (after <code>vehicleLicense</code> and <code>vehicleVin</code>),</li> <li>And just call the modified URL with <code>readHTMLTable</code> from <a href="http://cran.r-project.org/web/packages/XML/index.html" rel="nofollow noreferrer">XML</a> package which will provide you a nice data frame of the required dataset.</li> </ul> <p>So:</p> <pre><code>library(XML) datas <- readHTMLTable("http://www.dmv.ca.gov/wasapp/FeeCalculatorWeb/vlfFees.do?method=calculateVlf&su%C2%ADbmit=Determine%20VLF&vehicleLicense=5CWR968&vehicleTaxYear=2010&vehicleVin=11802") </code></pre> <p>And get the needed values of the table as @Rguy suggested above:</p> <pre><code>processed <- datas[[5]][[1]] paid <- datas[[5]][[2]] refund <- datas[[5]][[3]] </code></pre> <p>With this basic example you could easily write a loop the fetch all required data, but <strong>do not be greedy</strong> and do not loop without a sleep call (see: <code>Sys.sleep</code>). I would fetch only one plate per minute or so, which would definitely not bother the server much.</p>

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