a729a9e1d69997979c922c69f1cfb0f55cd5fe98
brianlee
  Sat Jun 25 07:49:13 2022 -0700
Expanding an example on trix.html, no RM

diff --git src/hg/htdocs/goldenPath/help/trix.html src/hg/htdocs/goldenPath/help/trix.html
index 464d4c7..08d18ec 100755
--- src/hg/htdocs/goldenPath/help/trix.html
+++ src/hg/htdocs/goldenPath/help/trix.html
@@ -1,44 +1,63 @@
 <!DOCTYPE html>
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 <h1>Trix Indices</h1> 
 <p>
 A Trix index consists of a pair of files that allow for fast look-up of free text associated with a 
 list of identifiers. The index is created from a single line-oriented text file using the program 
 <code>ixIxx</code>. Each line in the text file starts with an identifier, followed by free text 
 associated with the ID. For a more complete description of how to make a searchable track hub (or
 custom track), please visit the <a href="hubQuickStartSearch.html" target="_blank">Quick Start
 Guide to Searchable track hubs</a>.</p>
 <p>
 To complete the steps below you must first download the <code>ixIxx</code> utility. For more 
 information on downloading our command line utilities, see these 
 <a href="http://hgdownload.soe.ucsc.edu/downloads.html#source_downloads">instructions</a>.</p>
+<h3 id="ex1">Example 1</h3>
 <p>
 To create a Trix index, follow these steps:
 <ol>
   <li> 
   Prepare a text file that associates your IDs with free text:<br>
   <pre><code>    id1 this is text for id1
     id2 this is text for id2
     id3 this is text for id3</code></pre></li>
   <li>
   Run the <code>ixIxx</code> program on your text file.<br>
   <pre><code>    ixIxx input.txt myTrix.ix myTrix.ixx</code></pre></li>
 </ol>
+<h3 id="ex2">Example 2</h3>
+<ol>
+  <li>
+  If you have a bigBed track with unique gene names such as
+  <code>SIRT1, BRCA1, TP53</code> in the fourth name
+  column, and you built the bigBed using the option of
+  <code>-extraIndex=name</code> to index the name field you can create an
+  input.txt such as the following that associates the bigBed name with other
+  identifiers people might search for or with shorter spellings of the names:
+  <pre>
+    SIRT1 sirt1 sir sirt SIR SIRT Sirtuin SIR2-Like ENSG00000096717 NM_012238
+    BRCA1 brca1 brca brc BRC BRCA breast cancer 1 ENSG00000012048 NM_007300
+    TP53 tp53 tp5 TP5 Tumor Protein P53 ENSG00000141510 NM_001126112</pre></li>
+  <li>
+  You would then run the <code>ixIxx</code> program on your text file.<br>
+  <pre><code>    ixIxx input.txt myTrix.ix myTrix.ixx</code></pre></li>
+</ol>
+
 <h3 id="resources">Resources and examples</h3>
 <p>
 If you want to use your Trix index in a track hub, see the <code>searchTrix</code> setting in the 
 <a href="trackDb/trackDbHub.html#searchTrix">Track Database Definition Document</a>.</p>
 <p>
 Review our <a href="hubQuickStartSearch.html" target="_blank">Quick Start Guide to Searchable track hubs</a>
 for illustrated steps building a track hub.</p>
 <p>
 There are also tools available for taking genePred format to trix format, such as
 this <a href="https://genome-source.gi.ucsc.edu/gitlist/kent.git/blob/master/src/hg/utils/automation/gpToIx.pl"
 target="_blank">gpToIx.pl</a> perl script.</p>
 
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