title: Optimisation in R
body: <p>I'm new to R and I have a problem with optimisation.</p>
  
  <pre><code>d &lt;- c(0, 9.017, -9.017, 0, 9.017, 0, -8.579, -7.849, 0, 0, -7.849, 
      -9.017, 0, -7.849, -7.849, 0, 0, 0, 8.579, 1.168, 8.579, 8.579, 
      -7.849, 0.729, 8.579, 9.017, 0, -0.438)
  
  x &lt;- c(0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 
      1, 1, 0, 1, 1, 1, 0, 1)
  
  log.like&lt;-function (sigma){ 
      theta = pnorm(d,mean=0,sd=sigma) 
      logl = sum(log((theta ^ x) * ((1-theta)^(1-x))))
      -logl
  }
  
  optim(0,fn=log.like,method="L-BFGS-B",lower=0,upper=1)
  </code></pre>
  
  <p>It gives me the following error:</p>
  
  <pre><code> Error in optim(0, fn = log.like, method = "L-BFGS-B", lower = 0, upper = 1) : 
    L-BFGS-B needs finite values of 'fn'
  </code></pre>