# Decrease vertical space between text and equation

I am a new user of LaTex, I have some struggle. I want to reduce the vertical space between text and equation. There is a big gap between the equation and the text "Linearization of motion equations". I don't know how to do it, I've searched on the internet but it doesn't work for me:

\setlength{\belowdisplayskip}{0pt}
\setlength{\belowdisplayshortskip}{0pt}
\setlength{\abovedisplayskip}{0pt}
\setlength{\abovedisplayshortskip}{0pt}


You will find down below my code:

\begin{align*}
m\dot{v} &= Y + mg\sin\varphi\cos\theta + m(pw - ru) \\
I_{XX}\dot{p} &= L + (I_{YY} - I_{ZZ})qr \\
I_{ZZ}\dot{r} &= N +(I_{XX}-I_{YY})pq \\
\end{align*}

Linearization of motion equations
\begin{align*}
u &= U_0 + u(t) & v &= 0 + v(t) \\
p &= 0 + p(t) & r &= 0 + r(t) \\
\theta &= \theta_0 + \theta (t) & \varphi &= 0 + \varphi (t)
\end{align*} Thank you for your help :)

• the spacing you show in your output looks non standard but you have provided no code to reproduce the problem and test answers. Please post a full small document that makes the output shown, we can not process just fragments Apr 29, 2020 at 22:49
• it might be due to \flushbottom forcing the page to be full by stretching space, but hard to guess. Apr 29, 2020 at 22:51
• Welcome to TeX.sx! Please add a minimal working example (MWE) that illustrates your problem. Snippets of code are not enough to reproduce your situation and find the issue-s without having to guess what more could be also implied in that result. It is indeed better a compilable code, starting with \documentclass{...} and ending with \end{document}  and the minimal code (and no more) needed to produce exactly that result. The process of reduction to a MWE often solve the problem by itself.
– Fran
Apr 29, 2020 at 22:51

Considering that first of all are very important also the comments, just I have used \intertext option.

\documentclass[a4paper,12pt]{article}
\usepackage{mathtools,amssymb}

\begin{document}

\begin{align*}
m\dot{v} &= Y + mg\sin\varphi\cos\theta + m(pw - ru) \\
I_{XX}\dot{p} &= L + (I_{YY} - I_{ZZ})qr \\
I_{ZZ}\dot{r} &= N +(I_{XX}-I_{YY})pq \\
\intertext{Linearization of motion equations}
u &= U_0 + u(t) & v &= 0 + v(t) \\
p &= 0 + p(t) & r &= 0 + r(t) \\
\theta &= \theta_0 + \theta (t) & \varphi &= 0 + \varphi (t)
\end{align*}

\end{document} • Thanks! But I don't want the equation above to be aligned with the equation down below (Linearization of motion equations). How can I break it? Apr 30, 2020 at 7:46
• @NineLoup you still have not fixed your question to show why you have the large spaces, it is hard to tell you what to change if you do not show how you generated the space. Apr 30, 2020 at 9:53
• @NineLoup I'm totally agree with the comment of the very nice user David Carlisle. With lot patience it is very hard to built a complete code only with the fragments, because there are many approaches to solve your question. After it is very important to be clear (also I make mistakes, often using the English language). For me it is not important the votes but to help the users and to add further knowledges. Apr 30, 2020 at 10:34