title: Convert numbered to accentuated Pinyin?
body: <p>Given a source text like</p>
  
  <pre><code>nin2 hao3 ma
  </code></pre>
  
  <p>(which is a typical way to write ASCII Pinyin, without proper accentuated characters)
  and given a (UTF8) conversion table like</p>
  
  <pre><code>a1;ā
  e1;ē
  i1;ī
  o1;ō
  u1;ū
  ü1;ǖ
  A1;Ā
  E1;Ē
  ...
  </code></pre>
  
  <p>how would I convert the source text into</p>
  
  <pre><code>nín hǎo ma
  </code></pre>
  
  <p>?</p>
  
  <p>For what it's worth I'm using PHP, and this might be a regex I'm looking into?</p>