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1. • CommentRowNumber1.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 2nd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexmore examples <a href="https://ncatlab.org/nlab/revision/diff/Reedy+category/20">diff</a>, <a href="https://ncatlab.org/nlab/revision/Reedy+category/20">v20</a>, <a href="https://ncatlab.org/nlab/show/Reedy+category">current</a>

   more examples

   diff, v20, current

2. • CommentRowNumber2.
   • CommentAuthorYuxi Liu
   • CommentTimeJul 2nd 2020
   • PermaLink
   Author: Yuxi Liu
   Format: MarkdownItexmore Reedy category example, and the proof that all isomorphisms in a Reedy category are identities. <a href="https://ncatlab.org/nlab/revision/diff/Reedy+category/21">diff</a>, <a href="https://ncatlab.org/nlab/revision/Reedy+category/21">v21</a>, <a href="https://ncatlab.org/nlab/show/Reedy+category">current</a>

   more Reedy category example, and the proof that all isomorphisms in a Reedy category are identities.

   diff, v21, current

3. • CommentRowNumber3.
   • CommentAuthorMike Shulman
   • CommentTimeJan 28th 2021
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   Author: Mike Shulman
   Format: MarkdownItexI removed this paragraph from immediately following the definition: > That is, we have two subcategories $R_+$ and $R_-$, such that all arrows in $R_+$ are degree-raising (more precisely, non-degree-lowering) and all arrows in $R_-$ are degree-lowering, and every arrow in $R$ is uniquely decomposible as a degree-lowering followed by a degree-raising. I don't see that it adds anything; it just restates the definition in a less-precise and potentially confusing way. (And I just had an email conversation with someone who was actually confused by it.) <a href="https://ncatlab.org/nlab/revision/diff/Reedy+category/24">diff</a>, <a href="https://ncatlab.org/nlab/revision/Reedy+category/24">v24</a>, <a href="https://ncatlab.org/nlab/show/Reedy+category">current</a>

   I removed this paragraph from immediately following the definition:

   That is, we have two subcategories $R_+$ and $R_-$, such that all arrows in $R_+$ are degree-raising (more precisely, non-degree-lowering) and all arrows in $R_-$ are degree-lowering, and every arrow in $R$ is uniquely decomposible as a degree-lowering followed by a degree-raising.

   I don’t see that it adds anything; it just restates the definition in a less-precise and potentially confusing way. (And I just had an email conversation with someone who was actually confused by it.)

   diff, v24, current