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1. • CommentRowNumber1.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexjust testing latex code since there's no way to preview in the nLab editor Please get a preview button and a way to debug latex code it literally happens everytime I try to edit $$ \array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j } $$

   just testing latex code since there’s no way to preview in the nLab editor Please get a preview button and a way to debug latex code it literally happens everytime I try to edit

   $$\array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j }$$
2. • CommentRowNumber2.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexsubject to the following relations, called the **simplicial relations** or **[[simplicial identities]]**: $$ \array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j } $$ $$ \sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 < i } \right. $$ whenever $i, j$ are chosen so that the maps are defined. That is, in $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n $$ we implicitly require $0 \leq i, j \leq n$.

   subject to the following relations, called the simplicial relations or simplicial identities:

   $$\array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j }$$ $$\sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 < i } \right.$$

   whenever $i, j$ are chosen so that the maps are defined. That is, in

   $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n$$

   we implicitly require $0 \leq i, j \leq n$.

3. • CommentRowNumber3.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexsubject to the following relations, called the **simplicial relations** or **[[simplicial identities]]**: $$ \array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j } $$ $$ \sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 \leq i } \right. $$ whenever $i, j$ are chosen so that the maps are defined. That is, in $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n $$ we implicitly require $0 \leq i, j \leq n$.

   subject to the following relations, called the simplicial relations or simplicial identities:

   $$\array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j }$$ $$\sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 \leq i } \right.$$

   whenever $i, j$ are chosen so that the maps are defined. That is, in

   $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n$$

   we implicitly require $0 \leq i, j \leq n$.

4. • CommentRowNumber4.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexsubject to the following relations, called the **simplicial relations** or **[[simplicial identities]]**: $$ \array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j } $$ $$ \sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 \lt i } \right. $$ whenever $i, j$ are chosen so that the maps are defined. That is, in $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n $$ we implicitly require $0 \leq i, j \leq n$.

   subject to the following relations, called the simplicial relations or simplicial identities:

   $$\array{ \delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n & \qquad i \leq j \\ \sigma_j^n \circ \sigma_i^{n+1} = \sigma_i^n \circ \sigma_{j+1}^{n+1} & \qquad i \leq j }$$ $$\sigma_j^n \circ \delta_i^{n+1} = \left\lbrace \array{ \delta_i^n \circ \sigma_{j-1}^{n-1} & \qquad i \lt j \\ Id_n & \qquad i = j \;or\; i = j+1 \\ \delta^n_{i-1} \circ \sigma_{j}^{n-1} & \qquad j+1 \lt i } \right.$$

   whenever $i, j$ are chosen so that the maps are defined. That is, in

   $$\delta_i^{n+1} \circ \delta_j^n = \delta_{j+1}^{n+1}\circ \delta_i^n$$

   we implicitly require $0 \leq i, j \leq n$.

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItexFor testing code, better to use the $n$Lab entry _[[Sandbox]]_, i.e. * [ncatlab.org/nlab/show/Sandbox](https://ncatlab.org/nlab/show/Sandbox) because the parser and rendering here on the $n$Forums differs somewhat from that on the $n$Lab. Also, when you test in the Sandbox you avoid flooding the nForum with noise.

   For testing code, better to use the $n$Lab entry Sandbox, i.e.

   • ncatlab.org/nlab/show/Sandbox

   because the parser and rendering here on the $n$Forums differs somewhat from that on the $n$Lab.

   Also, when you test in the Sandbox you avoid flooding the nForum with noise.

6. • CommentRowNumber6.
   • CommentAuthorRodMcGuire
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: RodMcGuire
   Format: MarkdownItexumm there is a preview button in nForum so there is no need to actually `add your comment` after a test. The syntax in nForum appears to be a subset of nLab's so anything that works here should work there.

   umm there is a preview button in nForum so there is no need to actually add your comment after a test.

   The syntax in nForum appears to be a subset of nLab’s so anything that works here should work there.

7. • CommentRowNumber7.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItex@RodMcGuire The nforum preview button doesn't work for latex commands.

   @RodMcGuire The nforum preview button doesn’t work for latex commands.

8. • CommentRowNumber8.
   • CommentAuthorUrs
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItex> The syntax in nForum appears to be a subset of nLab’s so anything that works here should work there. I am fairly certain that there are some small differences in rendering, resulting from the fact, I think, that the rendering engine for published $n$Lab pages got updated in the past, but not synced with that for the $n$Forum (nor with that for pages in the $n$Lab history, for that matter). But yeah, in any case, the Sandbox is the [[Sandbox]] and this sandbox here is not a Sandbox.

   The syntax in nForum appears to be a subset of nLab’s so anything that works here should work there.

   I am fairly certain that there are some small differences in rendering, resulting from the fact, I think, that the rendering engine for published $n$Lab pages got updated in the past, but not synced with that for the $n$Forum (nor with that for pages in the $n$Lab history, for that matter).

   But yeah, in any case, the Sandbox is the Sandbox and this sandbox here is not a Sandbox.

9. • CommentRowNumber9.
   • CommentAuthorMike Shulman
   • CommentTimeJul 3rd 2020
   • PermaLink
   Author: Mike Shulman
   Format: MarkdownItexAlso, the nForum preview button does work for LaTeX for me. What browser are you using?

   Also, the nForum preview button does work for LaTeX for me. What browser are you using?

10. • CommentRowNumber10.
    • CommentAuthorRichard Williamson
    • CommentTimeJul 3rd 2020
    • (edited Jul 3rd 2020)
    • PermaLink
    Author: Richard Williamson
    Format: MarkdownItexI think maybe Yuxi meant things like \begin{theorem}. I don't have anything against trying to add preview functionality to the nLab in the long run, but it is non-trivial. In the meantime, it can be emphasised that editing several times after an initial edit to correct errors is fine and is actually the philosophy of the original Instiki software.

    I think maybe Yuxi meant things like \begin{theorem}. I don’t have anything against trying to add preview functionality to the nLab in the long run, but it is non-trivial. In the meantime, it can be emphasised that editing several times after an initial edit to correct errors is fine and is actually the philosophy of the original Instiki software.