n Unix.
The expression <code>${i}</code> substitutes in the value of loop index variable <code>i</code>.
To run chains in parallel, put an ampersand (<code>&amp;</code>) at the end of the nested sampler command:</p>
<pre><code>&gt; for i in {1..4}
    do
      ./bernoulli sample data file=bernoulli.data.json \
      output file=output_${i}.csv &amp;
    done</code></pre>
<p>This pushes each process into the background which allows the loop to continue
without waiting for the current chain to finish.</p>
<p>