R programming regarding types conversion
<p>I am trying to convert the data types in order to correctly plot the data.</p>

<p>In my opinion, my codes are a little bit complex and are not effective.</p>

<p>Therefore, I would like to ask some advice for better codes.</p>

<p>Below are my codes.</p>

<pre><code>pos &lt;- as.matrix(read.delim("urc_pos",header=FALSE))
neg &lt;- as.matrix(read.delim("urc_neg",header=FALSE))
rownames(pos) &lt;- 1:nrow(pos)
pos_temp &lt;- cbind("pos",pos[,3:42])
pos_temp_temp &lt;- as.data.frame(pos_temp)
for(i in 2:41)
{
    pos_temp_temp[,i] &lt;- as.numeric(as.character(pos_temp_temp[,i]))
}
</code></pre>

<p>urc_pos and urc_neg are my datasets.</p>

<p>For example, when I typed "is.numeric(pos[3,3])", it returned false because it was a vector. Therefore converting its data type to numeric type is necessary. After then, I assigned the row numbers and added label "pos" at the first column.</p>

<p>And below are the codes that convert the vector types to numerical type.
I think that it is a little bit complex and is unfavorable. Because I think that unnecessary procedures including converting data types ( data.frame -> character-> numerical) are involved in the for loops. </p>

<pre><code>pos_temp_temp &lt;- as.data.frame(pos_temp)
for(i in 2:41)
{
    pos_temp_temp[,i] &lt;- as.numeric(as.character(pos_temp_temp[,i]))
}
</code></pre>

<p>Anyway, I got the what I intended. when I typed "is.numeric(pos_temp_temp[3,3])", it returned TRUE.</p>

<p>However, I want to get the better solutions for this problems. 
I am looking forward to your answer :D</p>