title: Convert data frame row into new data frame column R
body: <p>I have a data frame, cul7_expr, with one row and 22 columns. I want to create a new data frame containing one column with all the numerical values from cul7_expr and another column with all the column names (TCGA.BC...). The new data frame would have 2 columns and 22 rows. However, when I try to take the row of cul7_expr, a warning pops up and the data frame is empty. </p>
  
  <p>Sample data (cul7_expr): </p>
  
  <pre><code>df &lt;- structure(list(TCGA.BC.A10Q.11A=819.3685,TCGA.BC.A10Q.01A=2757.486, 
  TCGA.DD.A1EB.11A=698.5818,TCGA.DD.A1EB.01A=1625.094,TCGA.DD.A1EG.11A=409.9332,
  TCGA.DD.A1EG.01A=2221.012,TCGA.DD.A1EH.11A=391.0916,TCGA.DD.A1EH.01A=2122.782, 
  TCGA.DD.A1EI.11A=717.2073,TCGA.DD.A1EI.01A=768.7468,TCGA.DD.A3A6.11A=464.6395,
  TCGA.DD.A3A6.01A=1175.928,TCGA.DD.A3A8.11A=934.9738,TCGA.DD.A3A8.01A=931.8955,
  TCGA.ES.A2HT.11A=599.736,TCGA.ES.A2HT.01A=894.8324,TCGA.FV.A23B.11A=970.1805,
  TCGA.FV.A23B.01A=3018.075,TCGA.FV.A3I0.11A=337.222,TCGA.FV.A3I0.01A=3895.477,
  TCGA.FV.A3R2.11A=912.8499,TCGA.FV.A3R2.01A=2226.921), 
  .Names=c("TCGA.BC.A10Q.11A","TCGA.BC.A10Q.01A","TCGA.DD.A1EB.11A",
  "TCGA.DD.A1EB.01A","TCGA.DD.A1EG.11A","TCGA.DD.A1EG.01A","TCGA.DD.A1EH.11A",
  "TCGA.DD.A1EH.01A","TCGA.DD.A1EI.11A","TCGA.DD.A1EI.01A","TCGA.DD.A3A6.11A", 
  "TCGA.DD.A3A6.01A","TCGA.DD.A3A8.11A","TCGA.DD.A3A8.01A","TCGA.ES.A2HT.11A", 
  "TCGA.ES.A2HT.01A","TCGA.FV.A23B.11A","TCGA.FV.A23B.01A","TCGA.FV.A3I0.11A",
  "TCGA.FV.A3I0.01A","TCGA.FV.A3R2.11A","TCGA.FV.A3R2.01A"),row.names = c(NA, -1L), 
  class = c("data.table","data.frame"))
  </code></pre>