title: Does Mpi Scatter send data in any kind of order
body: <p>I saw this on internet</p>
  
  <blockquote>
    <p>MPI_Scatter takes an array of elements and distributes the elements in the order of process rank.</p>
  </blockquote>
  
  <p>But I could not find it on the documentation.</p>
  
  <p>I have an array and there are 4 processes. One process is root -> will scatter data among other 3 processes. The id-s are 0, 1, 2, 3.</p>
  
  <p>Question: Will <code>MPI_Scatter()</code> or <code>MPI_Scatterv()</code> send the data in order, guaranteed? </p>
  
  <p>Example 1: </p>
  
  <pre><code>0: [a, b, c, d, e]
  
  // after scatter
  
  1: [a, b]
  2: [c, d]
  3: [e]
  </code></pre>
  
  <p>Example 2:</p>
  
  <pre><code>0: [a, b]
  
  // after scatter
  
  1: [a]
  2: [b]
  3: [ ]
  </code></pre>
  
  <p>Also, does gather do the same thing? (preserve order)</p>