amsmathequationsspacing
Is there a way to consistently increase the vertical spacing between equation lines in a gather (or gather*) environment from amsmath?
Specifically, I want to produce something like
\begin{gather*}
a = b \\[2ex]
c = d \\[2ex]
e = f
\end{gather*}
without having to write [2ex] at the end of each equation line.
I can think of some hacks that redefine \\ to automatically add the spacing, but is there some cleaner/better way to achieve this?
The SwapAboveDisplaySkipcommand from mathtools (mentioned by @Gustavo Mezzetti in his comment) doesn't work with multline, nor equation.
The \useshortskip from nccmath (to be used just before the environment, contrary to the mathtools solution, which has to be used at the beginning of the environment) works:
\documentclass[12pt]{article}
\usepackage[english]{babel}
\usepackage{mathtools, nccmath}
\begin{document}
\setlength\parindent{0pt}
Using \textit{equation}:
\begin{equation}
x = 1
\end{equation}
Spacing is OK.
\smallskip
(Using \textit{align}):\useshortskip
\begin{align}
x = 1
\end{align}
Spacing is OK.
\bigskip
(Using \textit{multline}):\useshortskip
\begin{multline}
x =a + b + c + d\\ + f +e +g + h
\end{multline}
Spacing is OK.
\end{document}
You can use the \useshortskip command from nccmath (just before the equation) or \SwapAboveDisplaySkip (at the very beginning of an amsmath environment):
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{mathtools, nccmath}
\begin{document}
In the first place, consider the relationship:
\begin{equation}\textit{A first equation} \end{equation}
where x is ... and y is ...
This is a new paragraph which ends with the following equation:\useshortskip
\begin{equation}\textit{Another equation} \end{equation}
This is another paragraph which ends with an AmSmath environment:
\begin{gather}\SwapAboveDisplaySkip\textit{Another equation} \end{gather}
And this is the last paragraph, followed by some equations which are not part of it.
\begin{equation}\textit{Still another equation}.\end{equation}
The end.
\end{document}
To reduce the spacing above and below an equation, we can patch an internal command of nccmath, but the following text must not start a new paragraph:
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{mathtools, nccmath}
\usepackage{xpatch}
\xpatchcmd{\NCC@ignorepar}{%
\abovedisplayskip\abovedisplayshortskip}
{%
\abovedisplayskip\abovedisplayshortskip%
\belowdisplayskip\belowdisplayshortskip}
{}{}
\begin{document}
In the first place, consider the relationship:
\begin{equation}\textit{A first equation} \end{equation}
where x is ... and y is ...
This is a new paragraph which ends with the following equation:\useshortskip
\begin{equation}\textit{Another equation}\text{(spacing with \texttt{\textbackslash useshortskips})}\end{equation}
And this is the last paragraph, followed by some equations which are not part of it.
\begin{equation}\textit{Still another equation}.\end{equation}
The end of this very exhaustive test.
\end{document}
Best Answer
This can be achieved by increasing the length
\jotwhich amsmath uses between lines in multi-line formulas. Either writeor
to increase the spacing. It's very similar to Increase spacing in split environment, since it's the same technique though another environment is meant.