title: Can I have a vector of vectors in R
body: <p>I want to produce all possible <code>w</code> when <code>s</code> range from -2 to 2 by 0.1, where 
  <code>w_min</code> and <code>w_max</code> are 5 x 1 vectors. But I don't know how to represent the result. I think I need a vector with each element as a vector, too, i.e., a vector of vectors.</p>
  
  <pre><code>s &lt;- seq(-2, 2, by = 0.1)
  
  result = c()
  
  for (i in 1:20) {
     w = s[i] * w_min + (1 - s[i]) * w_max
     ## what do I need to do here??
     }
  
  result
  </code></pre>