# How to increase the spacing between equations in “gather”?

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?

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See also this question. – Lev Bishop Sep 9 '10 at 15:46

This can be achieved by increasing the length \jot which amsmath uses between lines in multi-line formulas. Either write

\setlength{\jot}{value}


or

\addtolength{\jot}{value}


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.

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This assigment of \jot works only inside document text but not in preambule. How can I do this inside some my sty-package or, at least in a preambule? – maximav Nov 19 '13 at 7:51

Not sure if this is exactly what you're after, but the mathtools manual mentions, in relation to a new environment it provides, that the distance between lines in gather and other multiline environments is set by a dimension called \jot. By changing this length, e.g. \setlength{\jot}{2ex}, you can set it for the entire document.

Said environment is called spreadlines by the way, and changes this setting locally. This example is copied from the manual:

\begin{spreadlines}{20pt}
Large spaces between the lines.
\begin{gather}
a=b\\
c=d
\end{gather}
Back to normal spacing.
\begin{gather}
a=b\\
c=d
\end{gather}

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The traditional way (inherited from plain tex) is to do

\openup 2ex
\begin{gather*}
a = b \\
c = d \\
e = f
\end{gather*}


Although it's more traditional to use units of \jot rather than ex.

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