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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeSep 6th 2017
   • (edited Sep 6th 2017)
   • PermaLink
   Author: Urs
   Format: MarkdownItexRemind me, what do I need to type to make integral signs scale to a size appropriate for their integrands? I tried \left\int big integrand \right. but that doesn''t work. Here is an example that I would like to come out with larger integral symbols: $$ \begin{aligned} \underset{\epsilon \to 0^+}{\lim} \int \frac{e^{-i k_\mu (x-y)^\mu}}{ k_\mu k^\mu + m^2 + i k_0 \epsilon /2 } d^{p+1} k & = \underset{\epsilon \to 0^+}{\lim} \int \int \frac{ e^{-i k_0 x^0} e^{- i \vec k \cdot (\vec x - \vec y)} }{ - (k_0 - i \epsilon )^2 + E_\epsilon(\vec k)^2 } d k_0 d^p \vec k \\ & = \underset{\epsilon \to 0^+}{\lim} \int \frac{ e^{-i k_0 (x-y)^0} e^{- i \vec k \cdot (\vec x - \vec y)} }{ ( E_\epsilon(\vec k) + (k_0 - i \epsilon) ) ( E_\epsilon(\vec k) - (k_0 - i \epsilon) ) } d k_0 d^p \vec k \\ & = \left\{ \array{ 2\pi i \int \frac{ e^{-i E(\vec k) (x-y)^2 e^{-i \vec k \cdot (\vec x - \vec y)}} } { 2 E(\vec k) } - \frac{ e^{ + i E(\vec k)(x-y)^2} e^{-i \vec k \cdot (\vec x - \vec y)} }{ 2 E(\vec k) } & \vert & x^0 \gt 0 \\ 0 & \vert & x^0 \lt 0 } \right. \\ & = \cdots \end{aligned} $$

   Remind me, what do I need to type to make integral signs scale to a size appropriate for their integrands?

   I tried

    \left\int big integrand \right.
   

   but that doesn”t work.

   Here is an example that I would like to come out with larger integral symbols:

   $$\begin{aligned} \underset{\epsilon \to 0^+}{\lim} \int \frac{e^{-i k_\mu (x-y)^\mu}}{ k_\mu k^\mu + m^2 + i k_0 \epsilon /2 } d^{p+1} k & = \underset{\epsilon \to 0^+}{\lim} \int \int \frac{ e^{-i k_0 x^0} e^{- i \vec k \cdot (\vec x - \vec y)} }{ - (k_0 - i \epsilon )^2 + E_\epsilon(\vec k)^2 } d k_0 d^p \vec k \\ & = \underset{\epsilon \to 0^+}{\lim} \int \frac{ e^{-i k_0 (x-y)^0} e^{- i \vec k \cdot (\vec x - \vec y)} }{ ( E_\epsilon(\vec k) + (k_0 - i \epsilon) ) ( E_\epsilon(\vec k) - (k_0 - i \epsilon) ) } d k_0 d^p \vec k \\ & = \left\{ \array{ 2\pi i \int \frac{ e^{-i E(\vec k) (x-y)^2 e^{-i \vec k \cdot (\vec x - \vec y)}} } { 2 E(\vec k) } - \frac{ e^{ + i E(\vec k)(x-y)^2} e^{-i \vec k \cdot (\vec x - \vec y)} }{ 2 E(\vec k) } & \vert & x^0 \gt 0 \\ 0 & \vert & x^0 \lt 0 } \right. \\ & = \cdots \end{aligned}$$
2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeSep 6th 2017
   • (edited Sep 6th 2017)
   • PermaLink
   Author: Urs
   Format: MarkdownItexHm, now that I have sent this message here, I see that here on the nForum the integral signs _do_ scale appropriately. But on the $n$Lab they do not, see the present content of the _[[Sandbox]]_.

   Hm, now that I have sent this message here, I see that here on the nForum the integral signs do scale appropriately. But on the $n$Lab they do not, see the present content of the Sandbox.

3. • CommentRowNumber3.
   • CommentAuthorDavid_Corfield
   • CommentTimeSep 6th 2017
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexJacques Distler's [list](https://golem.ph.utexas.edu/~distler/blog/itex2MMLcommands.html) allows for size variation as follows: $ \displaystyle \int$, $\textstyle \int$, $\textsize \int$, $\scriptsize \int$, $\scriptscriptsize \int$.

   Jacques Distler’s list allows for size variation as follows: $\displaystyle \int$, $\textstyle \int$, $\textsize \int$, $\scriptsize \int$, $\scriptscriptsize \int$.

4. • CommentRowNumber4.
   • CommentAuthorMike Shulman
   • CommentTimeSep 6th 2017
   • PermaLink
   Author: Mike Shulman
   Format: MarkdownItexMaybe the problem is the `aligned` environment putting all its arguments in textstyle?

   Maybe the problem is the aligned environment putting all its arguments in textstyle?

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeSep 6th 2017
   • PermaLink
   Author: Urs
   Format: MarkdownItex@David, thanks, but it would be useful to have it scale automatically. @Mike, maybe. But in #1 above I also used the `aligned` environment.

   @David, thanks, but it would be useful to have it scale automatically.

   @Mike, maybe. But in #1 above I also used the aligned environment.

6. • CommentRowNumber6.
   • CommentAuthorMike Shulman
   • CommentTimeSep 6th 2017
   • PermaLink
   Author: Mike Shulman
   Format: MarkdownItexWell certainly there is a difference between the forum and the lab, I was just suggesting what might be causing the lab to behave oddly.

   Well certainly there is a difference between the forum and the lab, I was just suggesting what might be causing the lab to behave oddly.

7. • CommentRowNumber7.
   • CommentAuthorUrs
   • CommentTimeSep 6th 2017
   • (edited Sep 6th 2017)
   • PermaLink
   Author: Urs
   Format: MarkdownItexSure, thanks. So we might want to check if the "aligned"-environment behaviour for the $n$Lab could be tweaked. Maybe Adeel knows something about this.

   Sure, thanks. So we might want to check if the “aligned”-environment behaviour for the $n$Lab could be tweaked. Maybe Adeel knows something about this.