答案1
可以进行两项调整:
(1)垂直线分离,
(2)水平标签空间。
% !TeX TS-program = pdflatex
\documentclass[12pt,a4paper]{article}
\usepackage{amsmath}
\usepackage{proof}
\begin{document}
\noindent Original setup \\
\infer[(\implies I)]
{
(q \land r \land ¬s ) \implies ( u \lor r )
}
{
\infer[(\lor I r)]
{
\\u \lor r
}
{
\infer[(\land E_{2} r)]
{
r
}
{
q \land r
}
}
}
\vspace*{50pt}
\noindent Increase the line separation \\
\setlength{\inferLineSkip}{6pt} % increase the lines skip added <<<<<<
\infer[(\implies I)]
{
(q \land r \land ¬s ) \implies ( u \lor r )
}
{
\infer[(\lor I r)]
{
\\u \lor r
}
{
\infer[(\land E_{2} r)]
{
r
}
{
q \land r
}
}
}
\vspace*{50pt}
\noindent And also increase the labels separation \\
\setlength{\inferLabelSkip}{20pt} % <<<<<<< added
\infer[(\implies I)]
{
(q \land r \land ¬s ) \quad \implies \quad ( u \lor r ) %changed <<<<<<<<<<<<
}
{
\infer[(\lor I r)]
{
\\u \lor r
}
{
\infer[(\land E_{2} r)]
{
r
}
{
q \land r
}
}
}
\end{document
答案2
和bussproofs
:
\documentclass{article}
\usepackage{bussproofs}
\begin{document}
\begin{prooftree}
\AxiomC{$q\land r\mathstrut$} \RightLabel{$(\land E_2r)$}
\UnaryInfC{$rr\mathstrut$} \RightLabel{$(\lor Ir)$}
\UnaryInfC{$u\lor r\mathstrut$} \RightLabel{($\Rightarrow I$)}
\UnaryInfC{$(q\land r\land \lnot s)\Rightarrow(u\lor r)$}
\end{prooftree}
\end{document}