#LyX 2.4 created this file. For more info see https://www.lyx.org/
-\lyxformat 614
+\lyxformat 616
\begin_document
\begin_header
\save_transient_properties true
\use_default_options false
\begin_modules
subequations
+logicalmkup
\end_modules
\maintain_unincluded_children no
\language english
\html_be_strict false
\docbook_table_output 0
\docbook_mathml_prefix 1
+\author -584632292 "Richard Kimberly Heck"
\author -563046850 "Jean-Marc LASGOUTTES"
\author 177693 "x"
\author 5863208 "ab"
\end_inset
+\change_inserted -584632292 1686503213
+
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted -584632292 1686503316
+As is obvious,
+ commands defined in the preamble do not display `nicely' in LyX itself.
+ Most such commands can be defined in LyX using `math macros',
+ however,
+ which we are about to explain,
+ and these do display nicely.
+\change_unchanged
+
\end_layout
\begin_layout Subsection
\end_inset
+\change_inserted -584632292 1686503329
+
+\end_layout
+
+\begin_layout Subsection
+
+\change_inserted -584632292 1686503341
+Math Macros for External Commands
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted -584632292 1686503466
+Sometimes,
+ you may need to use a LaTeX package which defines a math command that is not natively supported in LyX.
+ This is easy enough to do:
+ Just include the package in the preamble and type out the command in math.
+ As with commands defined in the preamble,
+ however,
+ the display in LyX will not be `nice'.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted -584632292 1686503786
+As of LyX 2.4,
+ this problem has been solved.
+ Just define a math macro with empty LaTeX slot!
+ The LyX part will be used for display,
+ but no corresponding LaTeX will be output.
+ For example,
+ the
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -584632292 1686503714
+godelnum.sty
+\change_unchanged
+
+\end_layout
+
+\end_inset
+
+ package defines a Godelnum macro that puts a single argument into corner quotes.
+ To get a nice LyX display of this macro,
+ just do:
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted -584632292 1686503742
+\begin_inset FormulaMacro
+\newcommand{\Godelnum}[1]{}
+{\ulcorner#1\urcorner}
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted -584632292 1686503753
+The same trick,
+ of course,
+ can be used for commands defined in the preamble.
+\change_unchanged
+
\end_layout
\begin_layout Section