Graphics, Figures & Tables ⇒ Sum Limits above and below Operator instead of besides

[financialwar]

Code: Select all

\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}

The result is that {t=0} and {n} exists on the side of the Sum symbol instead of on direct top and bottom of the sum symbol.

How do I get it right?

[Stefan Kottwitz]

You could add \limits to change that:

Code: Select all

\sum\limits_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}

Here's an example for comparing different methods:

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\documentclass[10pt,a4paper]{article}
\usepackage{amsmath}
\begin{document}
\centering
$\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$
\[\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}\]
$\displaystyle\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$

$\sum\limits_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$
\end{document}

The first is inline math, then we see math in displayed style, the next one is inlined but switched to displayed style for the whole expression, the last one just tells \sum to use the limits above and below.

sum.png (11.72 KiB) Viewed 55876 times

Have a look at the excellent mathmode documentation to learn more about this.

Stefan

[localghost]

Due to missing information only some guesses.

• You are writing in in-line math mode.
  • add \limits after the \sum operator but before the limits.
  • add \displaystyle before the \sum operator.
  Note that this can disturb interline spacing.
• You are already writing in displayed math mode.
  • Remove the \nolimits command at all critical places in the concerned equations.
  • Remove the nolimits option from amsmath (or mathtools, or …)

And next time kindly prepare a proper minimal example to avoid guesswork.


Further reading:

• »Math mode«

Thorsten

[financialwar]

Code: Select all

$$\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$$

Code: Select all

$\displaystyle\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$

so basically these two are the same?

[Stefan Kottwitz]

Regarding size and limits, yes. But $...$ is for math within text, and $$...$$ is for displayed math, i.e. centered and within its own paragraph.

Stefan

[localghost]

Code: Select all

$$\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$$

Never use $$ … $$ for unnumbered displayed equations. Use \[ … \] instead.

[financialwar]

I see, thanks.

[financialwar]

Code: Select all

$$\sum_{t=0}^{n}\dfrac{CF_t}{(1+r)^t}$$

Never use $$ … $$ for unnumbered displayed equations. Use \[ … \] instead.

What do you mean by "unnumbered displayed equation"?

I thought $$ … $$ is the same as \[ … \].

Is there a good latex book for absolute beginner?

[localghost]

What do you mean by "unnumbered displayed equation"? […]

You know the difference between in-line and displayed equations? The latter ones can be automatically numbered by according environments (equation, align, …).

I thought $$ … $$ is the same as \[ … \]. […]

Both produce unnumbered displayed formulas. The first is TeX syntax, the latter is LaTeX syntax and thus preferable. Furthermore the TeX syntax causes some unwanted side effects. The below example demonstrates one of them.

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% TeX program = pdflatex
\documentclass[11pt,fleqn]{article}
\usepackage[T1]{fontenc}

\begin{document}
  \[ E=mc^2 \]
  $$ E=mc^2 $$
\end{document}

As you can see, equations written in TeX syntax are not affected by the fleqn (force left equations) option for the document class. For details see l2tabu.

[…] Is there a good latex book for absolute beginner?

Our topic »LaTeX Resources for Beginners« and the excellent »Math mode« document (which I already mentioned earlier).

[Stefan Kottwitz]

Is there a good latex book for absolute beginner?

I wrote the LaTeX Beginner's Guide, available in print and as ebook, also in Kindle format. There's free information available on the internet, but not always up to date, and if you prefer to tackle it hands on with a step-by-step guide, this book may help you.

Stefan