title: Quantile Mapping in R
body: <p>I am trying to bias correct PRECIS data for precipitation and temperature using different techniques for selecting the best one out of all.
  I am stuck up with an error while using '<code>qmap</code>' package in R. It helped in giving results for an area averaged (2D Netcdf) <code>dataset</code> in the form of a 2D plot which also showed improved correlation when validated with the observation <code>dataset</code>. 
  I am facing a problem when I am trying to run the same function over the entire 3D dataset. </p>
  
  <p>On running the following:</p>
  
  <pre><code>test=fitQmap(Observation_data,Model_data, method = 
  "PTF",transfun="scale",cost="RSS",wett.day=TRUE)
  </code></pre>
  
  <p>I am encountered with this error:</p>
  
  <pre><code> "Error in x[!nas] : object of type 'S4' is not subsettable"
  </code></pre>
  
  <p>Kindly help me out in getting rid of the error as I am a beginner in handling climate datests in R. Any help would be appreciated. </p>