# fleqn not left aligning two equations

I've looked at multiple similar queries but can't find a question with this specific issue. I've set the document class to fleqn which worked for other equations in my document, but not for equations 21 & 22 (see the image and code below).

I tried modifying the parameters to amsmath with fleqn which has the same effect. Also tried using  with no luck.

\documentclass[fleqn]{llncs}
...
\begin{align}
SC1 \mathlarger{\sum\limits_{j \in J}} x_{kjw} + s_{jkw}^{1} - s_{jkw}^{2} = d_{zjkw} ~~ \forall z \in Z, j \in J, k \in K, w \in W \\
SC2 \mathlarger{\sum\limits_{k \in K}} x_{kjwz_1} + s_{zjkw}^{3} - s_{zjkw}^{4} = 1 \\
SC3 \mathlarger{\sum\limits_{k \in K}} x_{kjwZ} + s_{zjkw}^{5} - s_{zjkw}^{6} = 1 \\
SC4 \mathlarger{\sum\limits_{k \in K}} [x_{ijkw} + x_{i(j+1)kw}] + s_{ijw}^{7} - s_{ijw}^{8} = 0,~ \forall i \in I, j \in J, w \in W
\end{align}

• you don't have any alignment points (&) specified in your alignment (normally just before the =) also why the \mathlarger which gives the expression a rather odd appearance as it's just round the summation? – David Carlisle Nov 7 '17 at 10:01
• That's it fixed now - thanks! imgur.com/x71f82D Simply put more senior researchers in my field have their equations in that fashion and I want to follow suit. Thanks for your assistance, David! Please put this as an answer so I can give you credit! – Ken Reid Nov 7 '17 at 10:11
• the summations still look like a poke in the eye set with \mathlarger but I removed that comment from the answer... – David Carlisle Nov 7 '17 at 10:16

You don't have any alignment points (&) specified in your alignment (normally just before the =)

For left alignment you need an alignment point, but in this case you can use gather, because there is no really good alignment point except the far left of all formulas.

Instead of the amazing \mathlarger{\sum\limits_{j\in J}} it's better to have a proper definition (so you can later redefine \lsum to be just \sum).

\documentclass[fleqn]{llncs}
\usepackage{relsize}
\usepackage{amsmath}

\makeatletter
\newcommand{\lsum}{\DOTSB\mathop{\mathlarger{\sum}}\slimits@}
\makeatother

\begin{document}

\paragraph{Ugly}
\begin{align}
SC1 \mathlarger{\sum\limits_{j \in J}} x_{kjw} + s_{jkw}^{1} - s_{jkw}^{2} = d_{zjkw} ~~ \forall z \in Z, j \in J, k \in K, w \in W \\
SC2 \mathlarger{\sum\limits_{k \in K}} x_{kjwz_1} + s_{zjkw}^{3} - s_{zjkw}^{4} = 1 \\
SC3 \mathlarger{\sum\limits_{k \in K}} x_{kjwZ} + s_{zjkw}^{5} - s_{zjkw}^{6} = 1 \\
SC4 \mathlarger{\sum\limits_{k \in K}} [x_{ijkw} + x_{i(j+1)kw}] + s_{ijw}^{7} - s_{ijw}^{8} = 0,~ \forall i \in I, j \in J, w \in W
\end{align}

\begin{gather}
\text{SC1}\,
\lsum_{j \in J} x_{kjw} + s_{jkw}^{1} - s_{jkw}^{2} = d_{zjkw}
\quad \forall z \in Z, j \in J, k \in K, w \in W \\
\text{SC2}\,
\lsum_{k \in K} x_{kjwz_1} + s_{zjkw}^{3} - s_{zjkw}^{4} = 1 \\
\text{SC3}\,
\lsum_{k \in K} x_{kjwZ} + s_{zjkw}^{5} - s_{zjkw}^{6} = 1 \\
\text{SC4}\,
\lsum_{k \in K} [x_{ijkw} + x_{i(j+1)kw}] + s_{ijw}^{7} - s_{ijw}^{8} = 0,
\quad \forall i \in I, j \in J, w \in W
\end{gather}

\paragraph{Good}
\begin{gather}
\text{SC1}\,
\sum_{j \in J} x_{kjw} + s_{jkw}^{1} - s_{jkw}^{2} = d_{zjkw}
\quad \forall z \in Z, j \in J, k \in K, w \in W \\
\text{SC2}\,
\sum_{k \in K} x_{kjwz_1} + s_{zjkw}^{3} - s_{zjkw}^{4} = 1 \\
\text{SC3}\,
\sum_{k \in K} x_{kjwZ} + s_{zjkw}^{5} - s_{zjkw}^{6} = 1 \\
\text{SC4}\,
\sum_{k \in K} [x_{ijkw} + x_{i(j+1)kw}] + s_{ijw}^{7} - s_{ijw}^{8} = 0,
\quad \forall i \in I, j \in J, w \in W
\end{gather}

\end{document}