invalid 'type' (character) of argument
<p>It is the error message on the topic. I am getting this error when I try to run naive.bayes classifier. Here is the summary of my train data:</p>

<pre><code>'data.frame':   7269 obs. of  193 variables:
 $ pid       : int  2 4 5 7 10 11 14 18 25 31 ...
 $ acquir    : int  0 0 0 0 1 1 0 0 0 0 ...
 $ addit     : int  0 0 0 0 2 2 0 0 0 0 ...
 $ agre      : int  0 0 0 0 0 0 0 0 0 0 ...
 $ agreement : int  0 0 0 0 0 0 0 0 0 0 ...
 $ also      : int  1 0 0 0 2 2 0 0 0 0 ...
 $ american  : int  0 0 0 0 0 0 0 0 0 0 ...
 $ announc   : int  0 0 0 0 0 0 0 0 0 0 ...
 $ annual    : int  0 0 0 0 0 0 0 0 2 0 ...
 $ approv    : int  0 3 0 0 0 0 0 0 0 0 ...
 $ april     : int  0 0 0 0 0 0 0 0 1 0 ...
 $ bank      : int  0 7 0 0 0 0 0 0 0 0 ...
 $ base      : int  0 0 0 0 0 0 0 0 0 0 ...
 .
 .
 $... all of them are integer, except the class column
 .
 .
 $ class     : Factor w/ 10 levels "acq","corn","crude",..: 1 1 4 4 9 1 4 3 1 4 ...
</code></pre>

<p>And this is the <code>naive.bayes()</code> line:</p>

<pre><code>model &lt;- naiveBayes(as.factor(class) ~ ., data = as.matrix(train), laplace = 3)
</code></pre>

<p>Can anyone tell me why it is happening?:</p>

<pre><code>Error in sum(x) : invalid 'type' (character) of argument
</code></pre>