During my research I noticed different sum signs:
The first one is mine and is created by $\sum_{i=1}^n$. The second one is from a paper. Any idea how to write it in LaTeX?
[Tex/LaTex] Different Sum signs
math-mode
Related Solutions
alignat is your friend:
\begin{alignat*}{2}
\sum a &\le &\sum b &\le \sum c \\
\log \sum a &\le{} &\log \sum b &\le \log \sum c
\end{alignat*}
produces:
I needed to add two extra alignment characters between the columns, and a {} to make the \le a binary operator. The number of &'s should be 2n-1 where n is the argument given (2 in the case above).
Although now that I read the question again I realize I didn't answer it. It seems that you want the \sum term to be centered...
The only way I can think of doing it is a bit ugly:
\newlength{\yuckkyhack}
\settowidth{\yuckkyhack}{$\displaystyle\log \sum b$}
\begin{alignat*}{2}
\sum a &{}\le{} &\makebox[\yuckkyhack]{$\displaystyle\sum b$} {}&\le \sum c \\
\log \sum a &\le{} &\log \sum b &\le \log \sum c
\end{alignat*}
which gives the desired result (I think):
but requires manual selection of the largest bit of text, and use of a length...any ideas for improvement?
The reason is the different height of the subscripts, t is smaller than k. One way to fix this (not beautiful, I know) is to put an invisible k below the first sum via \vphantom:
\begin{equation}
\Delta K_T^i = \sum_{\vphantom{k}t=1}^{T}\sum_{k=1}^{m}{\Delta K_t^{i,k}} = \sum_{t=1}^{T} {\Delta K_t^k}
\end{equation}
Best Answer
Adapting my answer here, Standard AMS-Sum Operator using MnSymbols?, for
mathptmx, you can use either font's sum operator (\summathptmx and\Xsumcomputer modern), while retaining the underlyingmathptmxmath font.If one uncomments the two lines in the MWE related to
fonttable, one will see the computer-modern math extension font table, showing the text and displaystyle sum signs at slots 80 and 88, which are reflected in my\DeclareMathSymboldeclarations.