title: Julia: Finding the elementwise maximum and minimum of a jagged array
body: <p>I have a jagged array of arrays. Like such below and I want to find the element-wise maximum and minimum, like shown below.</p>
  
  <pre><code>julia&gt; srand(0);
  julia&gt; triarr = [[rand(0:99, 2) for i in 1:j] for j in 1:3]
  3-element Array{Array{Array{Int64,1},1},1}:
  Array{Int64,1}[[40, 6]]                    
  Array{Int64,1}[[29, 77], [44, 74]]         
  Array{Int64,1}[[64, 23], [55, 8], [35, 37]]
  julia&gt; min.(vcat(triarr...)...)
  2-element Array{Int64,1}:
  29
  6
  julia&gt; max.(vcat(triarr...)...)
  2-element Array{Int64,1}:  
  64
  77
  </code></pre>
  
  <p>This works and looks clever but takes a lot of time for larger arrays. Is there an idiomatic Julia way of doing this?</p>