LaTex Indexing Tips–Fix Ascending Sub-Entries

1. If you are creating an index in LaTex where there will sub-entries, keep in mind that the order of the sub-entries must be descending so that they display properly.  So the syntax is 

\index{c!b!a}

or 

\index{Civil War!Battles!Gettysburg}

and not the other way around.

2. To create the index you must:

a. Run LaTex (or XeLaTex, or PDFLaTex or whatever engine you prefer)

b. Run makeindex (from the command line if your LaTex front-end doesn’t support it)

c. Run LaTex again. 

While these two points are pretty basic, I did not find them displayed clearly while rummaging around in the documentation.

Finally, if like me you indexed a long document putting the sub-entries in the wrong order, I can post a Python script that will fix things. Thanks to Tizen on Fiverr.com!