title: Convert rcpp variables into standard C++ variables
body: <p>My input looks like this:</p>
  
  <pre><code>Rcpp::NumericMatrix data(dataMatrix);
  Rcpp::NumericVector xSize(dataXsize);
  Rcpp::NumericVector ySize(dataYsize);
  Rcpp::NumericVector tIndexes(testIndexes);
  Rcpp::NumericVector cIndexes(controlIndexes);
  </code></pre>
  
  <p>And the external library I'm trying to call has this signature</p>
  
  <pre><code>WilcoxonTest(float * _data, int _dataXsize, int _dataYsize, vector&lt;int&gt; * _testIndexes, vector&lt;int&gt; * _controlIndexes);
  </code></pre>
  
  <p>How can I convert the Rcpp data types into C++ standard data types?</p>
  
  <p>Note: </p>
  
  <pre><code> float * _data
  </code></pre>
  
  <p>Is a matrix of floating point values. The library assumes its something like this:</p>
  
  <pre><code> float * _data = new float[dataXsize * dataYsize];
  </code></pre>