我有以下代码:
\begin{align*}
\xi(z)=0
&\iff
\begin{pmatrix}
\pi_P \circ z \circ \iota_P & \pi_P \circ z \circ \iota_Q \\
\pi_Q \circ z \circ \iota_P & \pi_Q \circ z \circ \iota_Q
\end{pmatrix}
= 0 \\
&\iff
\begin{aligned}
\pi_P \circ z \circ \iota_P = 0 ,\\
\pi_P \circ z \circ \iota_Q = 0 ,\\
\pi_Q \circ z \circ \iota_P = 0, \\
\pi_Q \circ z \circ \iota_Q = 0.
\end{aligned}
\end{align*}
生成以下代码片段
我的问题是:我怎样才能对我自己后续的四个方程式进行编号\标记(用字母\名称或其他方式编号或标记)?
我需要任何帮助。提前致谢。
答案1
类似这样的吗?
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{align}
ξ(z)=0 \notag
&\iff
\begin{pmatrix}
\pi_P ∘ z ∘ \iota_P & \pi_P ∘ z ∘ \iota_Q \\
\pi_Q ∘ z ∘ \iota_P & \pi_Q ∘ z ∘ \iota_Q
\end{pmatrix}
= 0 \\[1ex]
&\iff
\begin{aligned}
\pi_P ∘ z ∘ \iota_P & = 0 , &\qquad & (a)\\
\pi_P ∘ z ∘ \iota_Q & = 0 , & & (b)\\
\pi_Q ∘ z ∘ \iota_P & = 0, & & (c)\\
\pi_Q ∘ z ∘ \iota_Q & = 0. & & (d)
\end{aligned}%
\end{align}
\end{document}
答案2
如果需要交叉引用子方程,则需要使用单对齐环境,“移动”第二个子\iff
方程块到中间,然后手动“缩进”下一行:
\documentclass{article}
\usepackage{amsmath}
\usepackage{unicode-math}
\begin{document}
\begin{align}\nonumber
ξ(z)=0
&\iff
\begin{pmatrix}
\pi_P ∘ z ∘ \iota_P & \pi_P ∘ z ∘ \iota_Q \\
\pi_Q ∘ z ∘ \iota_P & \pi_Q ∘ z ∘ \iota_Q
\end{pmatrix}
= 0 \\[1ex]
&\smash{\lower1.5\baselineskip\hbox{$\strut\iff\strut$}} \pi_P ∘ z ∘ \iota_P = 0\,,\tag{1a}\\
&\hphantom{\strut\iff\strut} \pi_P ∘ z ∘ \iota_Q = 0\,,\tag{1b}\\
&\hphantom{\strut\iff\strut} \pi_Q ∘ z ∘ \iota_P = 0\,, \tag{1c}\\
&\hphantom{\strut\iff\strut} \pi_Q ∘ z ∘ \iota_Q = 0\,.\tag{1d}
\end{align}
\end{document}
我必须使用texlive2022lualatex
包unicode-math
才能运行它,但结果应该是这样的: