\int not coming out right

Question

I am trying to write this:

Using

$$p_{\Theta | X} = \frac{f_{\Theta}(\theta) p_{X|\Theta}(x\,|\,\theta)}{\int f_{\Theta}(\theta ') p_{X|\Theta}(x\,|\,\theta ') \, d\theta '}$$

However, what I get is this instead:

The integral sign does not come out right. Please help.

There are some intelligent people behind TeX and LaTeX. The behaviour you see is by design and what people usually want. Same for your other question. — Johannes_B, Jan 14 '20 at 04:19
@Mico, thank you! I have been wondering about the oddity of \,|\,. — J. Doe, Jan 14 '20 at 04:41
This is identical to your previous question on \sum, again what you show is the standard layout, not wrong, although other layouts could be chosen. — David Carlisle, Jan 14 '20 at 07:55

score 4 · Accepted Answer · answered Jan 14 '20 at 04:16

4

Add a \displaystyle command in front of the \int.

\documentclass{article}
\begin{document}
\[
f_{\Theta | X}(\theta | x) = \frac{f_{\Theta}(\theta) p_{X|\Theta}(x\,|\,\theta)}{\displaystyle\int f_{\Theta}(\theta ') p_{X|\Theta}(x\,|\,\theta ') \, d\theta '}
\]
\end{document}

Also, it's not related at all, but you should use \[...\] for display math mode, not $$...$$.

answered Jan 14 '20 at 04:16

Vincent

20,157

Thank you! That works. I am using Auto-LaTeX on Google Docs. Hence, $$...$$. – J. Doe Jan 14 '20 at 04:22
1

According to https://sites.google.com/site/autolatexequations/home, you can really use \[ ... \], don't you? "Only converts equations within $$ or \[ symbols, meaning you render only the equations you want to have rendered!" – ivankokan Jan 14 '20 at 04:30
1

@ivankokan, I didn't know that. Thank you! – J. Doe Jan 14 '20 at 06:19
Note that the scope of that \displaystyle affects the entire denominator not just the integral sign. – David Carlisle Jan 14 '20 at 07:56
I tried \[P_X\] and it did not work. $$P_X$$ works. Any idea? – J. Doe Jan 14 '20 at 07:58
1

@J.Doe in a latex document (as posted in examples on this site) if in some non tex system you need $$ for it to recognise the math fragment that may be the case but it's essentially off topic here. – David Carlisle Jan 14 '20 at 09:15
@J.Doe There is a drop-down selection in Auto-LaTeX Equations sidebar: Show Advanced Settings -> Select Delimiter Style. Although it seems that delimiters can be used exclusively, if you use both in your document, you can render both, e.g. select $$ ... $$ and click Render Equations, then select \[ ... \] and click Render Equations again. When it comes to Derendering, I found this comment on XXX website a bit confusing: "Same Delimiter Derendering - When you derender new equations now, they will have the same delimiters they were rendered with ($$...$$ or \[...\]) ." – ivankokan Jan 14 '20 at 09:51
@J.Doe I suggest you contact Auto-LaTeX and propose improvements. – ivankokan Jan 14 '20 at 09:51
@ivankokan, I will try your solution. I never got their Derendering working. – J. Doe Jan 14 '20 at 09:57
1

It works with \[...\] now. Derendering too. I guess previous attempts had complicated things it didn't like. – J. Doe Jan 14 '20 at 10:06

score 2 · Answer 2 · answered Apr 04 '20 at 14:15

You can try a pkg nccmath, here is a command \medint is useful

\documentclass{article}
\usepackage{nccmath}
\begin{document}
\[
f_{\Theta | X}(\theta | x) = \frac{f_{\Theta}(\theta) p_{X|\Theta}(x\,|\,\theta)}%
{\medint\int f_{\Theta}(\theta ') p_{X|\Theta}(x\,|\,\theta ') \, d\theta '}
\]
\end{document}

score 1 · Answer 3 · answered Apr 04 '20 at 20:45

Just only an addendum for the previous nice answers:

Using empheq to obtain the boxed formula with color;
Using \mid instead of \,|\, (as suggested by user @Mico) that it generates equal left and right blank space;
and...this link to choose your preferite background color called http://latexcolor.com/.

\documentclass[12pt,notitlepage]{book}
    \usepackage{mathtools,amssymb}
    \usepackage{empheq}
    \usepackage[x11names]{xcolor}
    \definecolor{lightgray}{rgb}{0.83, 0.83, 0.83}
    \begin{document}
    \begin{empheq}[box=\fcolorbox{lightgray}{lightgray}]{align}
    f_{\Theta \mid X}&=\frac{f_{\Theta}(\theta) p_{X\mid\Theta}(x\mid\theta)}{\displaystyle \int f_{\Theta}(\theta') p_{X|\Theta}(x\mid\theta') \, d\theta'}
    \end{empheq}
    \end{document}

\int not coming out right

3 Answers3