[Tex/LaTex] Complex nomenclature entries in LyX

Question

When I try to make a particularly complex nomenclature entry – in particular, inserting curly braces, and in specific, $E_{\left(A_i|B_I\right)}$ – the result simply doesn't appear in when the nomenclature entry later in the document. Everything else works fine – subscripts included, it's just the braces that seem to be broken.

Answer 1

Mico's suggestion to use \mid instead of | is not only for style but will fix your problem:

$E_{\left(A_i\mid B_I\right)}$

EDIT: as egreg notes, \left( and \right) do nothing as far as LaTeX is concerned here and in some cases they can add an unwanted space. I leave them here because that's what the OP has. Note that LyX renders the corresponding math differently (the left( and \right) parentheses are larger in LyX).

output:

Here is an MWE .lyx file:

#LyX 2.1 created this file. For more info see http://www.lyx.org/
\lyxformat 413
\begin_document
\begin_header
\textclass article
\use_default_options true
\maintain_unincluded_children false
\language english
\language_package default
\inputencoding auto
\fontencoding global
\font_roman default
\font_sans default
\font_typewriter default
\font_default_family default
\use_non_tex_fonts false
\font_sc false
\font_osf false
\font_sf_scale 100
\font_tt_scale 100
\graphics default
\default_output_format default
\output_sync 0
\bibtex_command default
\index_command makeindex -g
\paperfontsize default
\spacing single
\use_hyperref false
\papersize default
\use_geometry false
\use_amsmath 1
\use_esint 1
\use_mathdots 1
\use_mhchem 1
\cite_engine basic
\use_bibtopic false
\use_indices false
\paperorientation portrait
\suppress_date false
\use_refstyle 1
\index Index
\shortcut idx
\color #008000
\end_index
\secnumdepth 3
\tocdepth 3
\paragraph_separation indent
\paragraph_indentation default
\quotes_language english
\papercolumns 1
\papersides 1
\paperpagestyle default
\tracking_changes false
\output_changes false
\html_math_output 0
\html_css_as_file 0
\html_be_strict false
\end_header

\begin_body

\begin_layout Standard
\begin_inset CommandInset nomenclature
LatexCommand nomenclature
symbol "$E_{\\left(A_i\\mid B_I\\right)}$"
description "description..."

\end_inset


\end_layout

\begin_layout Standard
\begin_inset CommandInset nomencl_print
LatexCommand printnomenclature
set_width "auto"

\end_inset


\end_layout

\end_body
\end_document

And exported to LaTeX (pdflatex):

%% LyX 2.1.0dev created this file.  For more info, see http://www.lyx.org/.
%% Do not edit unless you really know what you are doing.
\documentclass[english]{article}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\usepackage{nomencl}
% the following is useful when we have the old nomencl.sty package
\providecommand{\printnomenclature}{\printglossary}
\providecommand{\makenomenclature}{\makeglossary}
\makenomenclature
\usepackage{babel}
\begin{document}
\nomenclature{$E_{\left(A_i\mid B_I\right)}$}{description...}

\settowidth{\nomlabelwidth}{$E_{\left(A_i\mid B_I\right)}$}
\printnomenclature{}
\end{document}