Big-Data-HPC-Platform/docs/ECLProgrammersGuide/PRG_Mods/PrG_NonRandom_Random.xml

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"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<sect1 id="Non-Random_RANDOM">
  <title><emphasis role="bold">Non-Random RANDOM</emphasis></title>

  <para>There are occasions when you need a random number, but once
  you've gotten it, you want that value to stay the same for the duration of
  the workunit. For example, the “problem” with this code is that it will
  OUTPUT three different values (this code is in
  NonRandomRandom.ECL):</para>

  <programlisting>INTEGER1 Rand1 := (RANDOM() % 25) + 1;
OUTPUT(Rand1);
OUTPUT(Rand1);
OUTPUT(Rand1);</programlisting>

  <para>To make the “random” value persistent throughout the workunit, you can
  simply add the STORED Workflow Service to the attribute definition, like
  this (this code is also in NonRandomRandom.ECL):</para>

  <programlisting>INTEGER1 Rand2 :<guimenu>=</guimenu> (RANDOM() % 25) + 1 : STORED('MyRandomValue');
OUTPUT(Rand2);
OUTPUT(Rand2);
OUTPUT(Rand2);</programlisting>

  <para>This will cause the “random” value to be calculated once, then used
  throughout the rest of the workunit.</para>

  <para>The GLOBAL Workflow Service would accomplish the same thing, but using
  STORED has the added advantage that the “random” value used for the workunit
  is displayed on the ECL Watch page for that workunit, allowing you to better
  debug your code by seeing exactly what “random” value was used for the
  job.</para>
</sect1>