title: how to read a matrix from text file in R
body: <p>I have a text file name "A.txt" . In there , I have the following data: </p>
  
  <pre><code>1 3 4 
  2 3 4 
  5 6 7 
  </code></pre>
  
  <p>I want to read it and save as A vector in R software . How can I do that ? </p>
  
  <p>Update : </p>
  
  <p>I have tried by the following code : </p>
  
  <pre><code>R&gt; dat &lt;- as.numeric(readLines('D:/Simplex/SimplexInitialTheoryWithRsoftware/src/A.txt'))
  R&gt;  dat.matrix &lt;- matrix(dat, nrow=??)
  </code></pre>
  
  <p>But I have the following error . </p>
  
  <p>Eror: unexpected ')' in "dat.matrix &lt;- matrix(dat, nrow=??)"</p>
  
  <p>I am very new in this software . Please help me </p>