title: neuralnet for multiple regression
body: <p>I have a data frame, <code>Data</code>, which has 10 columns. First 6 are input values and the next 4 columns are output values. </p>
  
  <pre><code>head(Data)
  x1        x2       x3       x4       x5      x6      y1       y2     y3       y4
  200       400      1.8     100       50      10     3884     3.9    5.98     1.91
  </code></pre>
  
  <p>I want to use neural network to predict the values of outputs by using <code>neuralnet</code> package. When I use the following code, I am getting an error as following:</p>
  
  <pre><code>model &lt;- neuralnet(Data[1:30,1:6], Data[1:30,7:10], data=Data, hidden=c(5,7), err.fct="ce", linear.output=FALSE)
  
  Error in varify.variables(data, formula, startweights, learningrate.limit,  : 
    (list) object cannot be coerced to type 'double'
  </code></pre>
  
  <p>Could you please tell me what's wrong with this code?</p>