title: How to concatenate numeric columns in R?
body: <p>I have three columns of x, y, and z coordinates in a dataframe in R that I would like to concatenate into one xyz value, like below. I have tried 'paste' with 'collapse'="" and sep="" but am having trouble, I think it's something to do with text vs. numeric variables.</p>
  
  <pre><code>I have:
  x y z 
  1 2 3 
  2 3 2 
  3 1 4 
  4 2 1 
  
  I want:
  x y z xyz
  1 2 3 123
  2 3 2 232
  3 1 4 314
  4 2 1 421
  </code></pre>
  
  <p>There has to be some extremely easy/simple way to do this in R but I have been Googling and looking through Stack Overflow off-and-on for the past couple days and nothing has come to my attention. All I need is the xyz column to be unique so I can run fixed-effects regressions, (x ranges from 1:4, y from 1:4 and z 1:10) so I have 160 possible combinations. Currently I am using different exponents on the x, y, and z values and then multiplying them to get unique values--surely there's a better way! Thanks</p>