title: R rms package error when using rcs()
body: <p>Been looking into Harrell's <code>rms</code> package for R and I am getting an error whenever I try to use the spline function <code>rcs()</code> inside a formula.  This happens with all datasets.  Is there some R setting I am missing?</p>
  
  <pre><code>library(rms)
  
  df = read.csv("http://www.ats.ucla.edu/stat/data/binary.csv")
  
  m = lrm(admit~ rcs(gre), df)
  
  
  Error in rcspline.eval(x, nk = nknots, inclx = TRUE, pc = pc, fractied = fractied) : 
    unused argument (fractied = fractied)
  </code></pre>
  
  <p>What is "fractied"?  I haven't been able to find a clear explanation.</p>
  
  <p>I'm using Windows 7, R version 3.1.0, rms version 4.2.0</p>