[Tex/LaTex] Align objective function in latex

alignspacing

I am writing the following optimization model:

\documentclass{article}
\usepackage[cmex10]{amsmath}

\DeclareMathOperator*{\Min}{min}

\begin{document}

\begin{align}
&Q_t(v_{t-1},a_{ti\omega}) = \notag \\ 
&\min_{\substack{g_t,~y_t,f_t,~\theta_t,~\\\Delta u^{up},~\Delta u^{dn},\\\Delta g^{up},~\Delta g^{dn},\\g_t^c,~y_t^c,~f_t^c,~\theta_t^c}} c^\top_{t}g_{t,i}+\sum_{i \in \mathcal{I}^T}(c^{U}_i \Delta g^{up}_{t,i}+c^{D}_i \Delta g^{dn}_{t,i})+ \notag \\
&\hspace{19mm}\sum_{i \in \mathcal{I}^H}(c^{U}_i \Delta u^{up}_{t,i}+c^{D}_i \Delta u^{dn}_{t,i})+\mathcal{Q}_{t+1}(v_t)
\end{align}
\end{document}

However, I wanted both parts of the objective function to be close. I do not want that vertical space between them. Is there a way around?

Best Answer

If you really want align, you can add or remove space when breaking a line. In this case, at the second line break, replacing \\ with \\[-2em] reduces the vertical spacing:

\documentclass{article}
\usepackage[cmex10]{amsmath}    
\DeclareMathOperator*{\Min}{min}
\begin{document}

\begin{align}
&Q_t(v_{t-1},a_{ti\omega}) = \notag \\ 
&\min_{\substack{...} c^\top_{t}g_{t,i}+\sum_{i \in \mathcal{I}^T}(c^{U}_i \Delta
g^{up}_{t,i}+c^{D}_i \Delta g^{dn}_{t,i})+ \notag \\[-2em] % here
&\hspace{19mm}\sum_{i \in \mathcal{I}^H}(c^{U}_i \Delta u^{up}_{t,i}+c^{D}_i \Delta u^{dn}_{t,i})+\mathcal{Q}_{t+1}(v_t)
\end{align}
\end{document}

This works in environments other than align, too, in case you want to switch.

Related Solutions

[Tex/LaTex] Latex align error

First of all, you're missing a matching \right delimiter to one of your \left delimiters.

Also, you cannot break \left and \right across lines inside align (or any math environment for that matter). You need to do this manually by using a fake opposing delimiter and introducing the necessary false heights to obtain equivalent delimiters. However, an easier alternative would be to use non-matching "big" operators:

enter image description here

\documentclass{article}
\usepackage{amsmath}% http://ctan.org/pkg/amsmath
\begin{document}
\begin{align}
  \rlap{$C(t,xxx,\tau,N,X)$}\hspace{2em} & \nonumber \\
    &= N\Phi\sum_{i=1}^{n}
      \Bigg[-(1+X_{\tau_{i}})P(t,T_{i})
        \Bigg(\frac{\ln\frac{P(t,T_{i-1})}{(1+X_{\tau_{i}}P(t,T_{i})}}{\Sigma(t,T_{i-1},T_{i})}-\frac{1}{2}\Sigma(t,T_{i-1},T_{i})\Bigg)\\
    &\phantom{{}={}} {}+P(t,T_{i-1})\Bigg[
      \Bigg(\frac{\ln\frac{P(t,T_{i-1})}{(1+X_{\tau_{i}})P(t,T_{i})}}{\Sigma(t,T_{i-1},T_{i})}-\frac{1}{2}\Sigma(t,T_{i-1},T_{i})\Bigg)\Bigg]\Bigg]
\end{align}
\end{document}

The use of \hspace in the first line is to make the equation fit within the text block width. Also note the use of \phantom{{}={}} to obtain the correct spacing for the second numbered equation.

[Tex/LaTex] Labeled linear program with labeled equations and wide objective function

I've taken some liberties in interpreting what you're trying to accomplish here. For example, I assume that you will manually create the tag names for the LP blocks. Also, I think my solution lacks a certain elegance: in particular, each such block has to be created separately. I don't really like that.

Here's the general idea: create two adjacent boxes centered on the baseline with one containing a dummy equation to create the label for the entire block. Spacing after the boxes is a bit wonky. So, I add ~ after the last flalign environment. (Short coming: you also have to manually adjust the width of the first parbox to get the label to be positioned correctly.)

You seemed to want the first line to somehow align with the LP. I've got two solutions to that. The first puts the first line into a box of zero width. (Short coming: you have to re-enter math mode within this box.) The second puts this first line in its own flalign environment. (Short coming: you have to adjust the vertical spacing between the two environments.)

\documentclass{article}
\usepackage{amsmath,calc}
\newlength{\LPlhbox}
\begin{document}


\settowidth{\LPlhbox}{(P.1)}%
\noindent%
\parbox{\LPlhbox}{\begin{align}
               \tag{P.1}\label{My first LP Block}
               \end{align}}%
\hspace*{\fill}%
\begin{minipage}{\linewidth-2cm}
    \begin{flalign}\notag
     & \makebox[0pt][l]{$\displaystyle{}\max \sum\limits_{v \in V} x_v + \sum\limits_{e \in E} y_e + 10000\gamma$} \\
    \label{this line can be referenced}
     & \text{s.t.} & x_v + x_w   & \geq  0                 && \forall \{v,w\} \in E && \\
     &             & y_3         & \geq 0                  && \forall e\in E        && \\
     &             & (\delta(U)) & \geq \frac{1}{2}(|U|-1) && \forall U \subseteq V
    \end{flalign}~
\end{minipage}

\settowidth{\LPlhbox}{(P.2)}%
\noindent%
\parbox{\LPlhbox}{\begin{align}
               \tag{P.2}\label{My second LP Block}
               \end{align}}%
\hspace*{\fill}%
\begin{minipage}{\linewidth-2cm}
   \begin{flalign}\notag
     \max \sum\limits_{v \in V} x_v + \sum\limits_{e \in E} y_e + 10000\gamma &&
   \end{flalign}
    \vspace{-1.5\baselineskip}
   \begin{flalign}
    & \text{s.t.} & x_v + x_w   & \geq  0                 && \forall \{v,w\} \in E && \\
    &             & y_3         & \geq 0                  && \forall e\in E        && \\
    &             & (\delta(U)) & \geq \frac{1}{2}(|U|-1) && \forall U \subseteq V
   \end{flalign}~
\end{minipage}

Notice that we can reference line~\ref{this line can be referenced}
and both block~\ref{My first LP Block} and block~\ref{My second LP Block}
\end{document}

What would be nice is if there were a commands \lefttag and \righttag to temporarily override document defaults.

You can also easily create a command to do the work of the left-hand box.

\newcommand{\LPblocktag}[2]{\settowidth{\LPlhbox}{(#1)}%
                            \parbox{\LPlhbox}{\begin{align}\tag{#1}#2\end{align}}%
                            \hspace*{\fill}}

I've written the second argument as I have because I don't want to assume you'll be referencing every such block.

So the first block above can be written as

\noindent%
\LPblocktag{P.3}{\label{My third LP Block}}%
\begin{minipage}{\linewidth-2cm}
    \begin{flalign}\notag
     & \makebox[0pt][l]{$\displaystyle{}\max \sum\limits_{v \in V} x_v + \sum\limits_{e \in E} y_e + 10000\gamma$} \\
    \label{this line can be referenced}
     & \text{s.t.} & x_v + x_w   & \geq  0                 && \forall \{v,w\} \in E && \\
     &             & y_3         & \geq 0                  && \forall e\in E        && \\
     &             & (\delta(U)) & \geq \frac{1}{2}(|U|-1) && \forall U \subseteq V
    \end{flalign}~
\end{minipage}

I can reference \ref{My third LP Block}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Latex align error

[Tex/LaTex] Labeled linear program with labeled equations and wide objective function

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