how to map column names to row minimum value : <p>I have the following data:</p>

<pre><code>df
     dc1  dc2  dc3   min_colname
[1,] 12.9 13.4 13.4
[2,]  6.1  6.5  6.5
[3,]  6.3  6.7  6.7
[4,] 21.0 21.4 21.4
[5,]  1.6  1.8  1.8
[6,]  3.3  3.7  3.7
[7,]  7.0  7.4  7.4
[8,]  3.2  3.6  3.6
[9,] 14.8 15.2 15.2
[10,]  7.9  8.3  8.3
</code></pre>

<p>I am trying to add one more column say <code>min_colname</code> which will have the min values of each row but mapped to column name....for example for row 1 min value is <code>12.9</code>..so the first item in min_colname should be <code>dc1</code> and not the actual obs value.....</p>
