title: Error in 1:N : NA/NaN argument
body: <p>I'm using this data:<a href="https://www.dropbox.com/s/m02z4ykirfc1838/data.txt?dl=0" rel="nofollow noreferrer">https://www.dropbox.com/s/m02z4ykirfc1838/data.txt?dl=0</a></p>
  
  <p>I'm trying to run the following model:</p>
  
  <pre><code>inputs&lt;- data.frame(data[,c(1,2,3,4,5)]) # seleciona coluna 2 do objeto data
  outputs &lt;- data.frame(data[,c(6,7)]) # seleciona colunas 3, 4 e 5 do objeto data
  N&lt;- dim(data)[19] # número de DMUs
  s &lt;- dim(inputs)[5] # número de inputs
  m &lt;- dim(outputs)[2] # número de outputs
  f.rhs &lt;- c(rep(0,1,N),1) # RHS
  f.dir &lt;- c(rep("&lt;=",1,N),"=") # direção das restrições
  aux &lt;- cbind(-1*inputs,outputs) # matriz com os coeficientes tecnológicos em (6)
  for (i in 1:N) {
  f.obj &lt;- c(0*rep(1,s),as.numeric(outputs[i,])) # coeficientes da função objetivo
  f.con &lt;- rbind(aux ,c(as.numeric(inputs[i,]), + rep(0,1,m))) # adiciona a restrição b
  T
  z=1
  results &lt;- lp("max",as.numeric(f.obj),f.con,f.dir,f.rhs,scale=1,compute.sens=TRUE) # resolve PPL
  multipliers &lt;- results$solution # multiplicadores
  efficiency &lt;- results$objval # indices de eficiência
  duals &lt;- results$duals # 
  if (i==1) {
   weights &lt;- multipliers
   effcrs &lt;- efficiency
   lambdas &lt;- duals [seq(1,N)]
  } else {
   weights &lt;- rbind(weights,multipliers)
   effcrs &lt;- rbind(effcrs , efficiency)
   lambdas &lt;- rbind(lambdas,duals[seq(1,N)])
  }
  } 
  </code></pre>
  
  <p>However, I get this error stuff:</p>
  
  <p>Error in 1:N : NA/NaN argument</p>
  
  <p>I really need a hand on it.</p>