#LyX 2.3 created this file. For more info see http://www.lyx.org/ \lyxformat 544 \begin_document \begin_header \save_transient_properties true \origin /systemlyxdir/examples/ \textclass article \use_default_options true \begin_modules subequations \end_modules \maintain_unincluded_children false \language english \language_package default \inputencoding auto \fontencoding global \font_roman "default" "default" \font_sans "default" "default" \font_typewriter "default" "default" \font_math "auto" "auto" \font_default_family default \use_non_tex_fonts false \font_sc false \font_osf false \font_sf_scale 100 100 \font_tt_scale 100 100 \use_microtype false \use_dash_ligatures false \graphics default \default_output_format default \output_sync 0 \bibtex_command default \index_command default \paperfontsize default \spacing single \use_hyperref false \papersize default \use_geometry false \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 1 \use_package esint 1 \use_package mathdots 1 \use_package mathtools 1 \use_package mhchem 1 \use_package stackrel 1 \use_package stmaryrd 1 \use_package undertilde 1 \cite_engine basic \cite_engine_type default \biblio_style plain \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \justification true \use_refstyle 1 \index Index \shortcut idx \color #008000 \end_index \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \is_math_indent 0 \math_numbering_side default \quotes_style english \dynamic_quotes 0 \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 \use_minted 0 \end_header \begin_body \begin_layout Standard The \family typewriter subequations \family default environment is provided in LyX by the \family typewriter subequations \family default module (Document > Settings > Modules). It is helpful to group logically-linked equations. For example, the one-speed one-dimensional integro-differential equation with \begin_inset Formula $0\le x\le X$ \end_inset and \begin_inset Formula $-1\le\mu\le1$ \end_inset shown in Eq. \begin_inset space ~ \end_inset \begin_inset CommandInset ref LatexCommand ref reference "eq:odoglbe" \end_inset has associated boundary conditions shown in Eqs. \begin_inset space ~ \end_inset \begin_inset CommandInset ref LatexCommand ref reference "eq:rlbc" \end_inset and \begin_inset CommandInset ref LatexCommand ref reference "eq:vrbc" \end_inset . \begin_inset Flex Subequations status open \begin_layout Plain Layout \begin_inset Formula \begin{align} \mu\frac{d\psi\left(x,\mu\right)}{dx}+\Sigma_{t}\left(x\right)\psi\left(x,\mu\right) & =\intop_{-1}^{1}\frac{\Sigma_{s}\left(x,\mu'\to\mu\right)}{2}\psi\left(x,\mu'\right)d\mu'+\frac{Q\left(x,\mu\right)}{2},\label{eq:odoglbe}\\ \psi\left(0,\mu\right) & =\psi\left(0,-\mu\right)\,,\,0<\mu\le1,\label{eq:rlbc}\\ \psi\left(X,\mu\right) & =0\,,\,-1\le\mu<0.\label{eq:vrbc} \end{align} \end_inset \begin_inset CommandInset label LatexCommand label name "eq:odoglbeset_aligned" \end_inset \end_layout \end_inset \end_layout \begin_layout Standard In the previous case, the equations use the \family typewriter amsmath \family default \family typewriter align \family default environment; however, this is not necessary as shown in Eqs. \begin_inset space ~ \end_inset \begin_inset CommandInset ref LatexCommand ref reference "eq:odoglbenoa" \end_inset – \begin_inset CommandInset ref LatexCommand ref reference "eq:vrbcnoa" \end_inset . \begin_inset Flex Subequations status open \begin_layout Plain Layout \begin_inset Formula \begin{equation} \mu\frac{d\psi\left(x,\mu\right)}{dx}+\Sigma_{t}\left(x\right)\psi\left(x,\mu\right)=\intop_{-1}^{1}\frac{\Sigma_{s}\left(x,\mu'\to\mu\right)}{2}\psi\left(x,\mu'\right)d\mu'+\frac{Q\left(x,\mu\right)}{2},\label{eq:odoglbenoa} \end{equation} \end_inset \begin_inset Formula \begin{equation} \psi\left(0,\mu\right)=\psi\left(0,-\mu\right)\,,\,0<\mu\le1,\label{eq:rlbcnoa} \end{equation} \end_inset \begin_inset CommandInset label LatexCommand label name "eq:odoglbeset_individual" \end_inset \begin_inset Formula \begin{equation} \psi\left(X,\mu\right)=0\,,\,-1\le\mu<0.\label{eq:vrbcnoa} \end{equation} \end_inset \end_layout \end_inset \end_layout \begin_layout Standard As an alternative to cross-referencing each subequation directly, the group of subequations (i.e., Eq. \begin_inset space ~ \end_inset \begin_inset CommandInset ref LatexCommand ref reference "eq:odoglbeset_aligned" \end_inset and/or Eq. \begin_inset space ~ \end_inset \begin_inset CommandInset ref LatexCommand ref reference "eq:odoglbeset_individual" \end_inset ) can be referenced by placing a label within the subequation inset but outside the equation(s). \end_layout \end_body \end_document