I was motivated to make a diagram of IDL's operators by Mark Lentczner's [Periodic Table of the Operators](http://www.ozonehouse.com/mark/blog/code/PeriodicTable.html) in Perl. IDL doesn't have nearly as many operators as Perl, so the IDL Periodic Table is much sparser. I added some operators not listed in the [table of precedence](http://idlastro.gsfc.nasa.gov/idl_html_help/Operator_Precedence.html) in the online help. Order of precedence was determined empirically.
Here's the table along with the code and data to make it: [`mg_make_op_table.pro`](http://michaelgalloy.com/demos/table-of-operators/mg_make_op_table.pro) ([docs](http://michaelgalloy.com/demos/table-of-operators/mg_make_op_table.html)), [`mgffxmlsaloperators__define.pro`](http://michaelgalloy.com/demos/table-of-operators/mgffxmlsaxoperators__define.pro) ([docs](http://michaelgalloy.com/demos/table-of-operators/mgffxmlsaxoperators__define.html)), and [`operators.xml`](http://michaelgalloy.com/demos/table-of-operators/operators.xml). `MGffXMLSAXOperators` is an example of using IDL's SAX parser (and object-graphics).