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Is there a difference between \dots and \ldots, the ellipsis?

If yes: Which? When to use \dots and when to use \ldots?

If no: Why are there both at all?

ᴇɴᴅᴇʀᴍᴀɴ
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Foo Bar
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1 Answers1

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in latex.ltx, \ldots is equated (\let) to \dots. so in text, it's the same, and you can use either.

with amsmath, the situation is more complicated; \dots tries to determine by context (only in math mode) whether to use \ldots or \cdots, with several more options for the author if amsmath doesn't get it right.

so in general, it's easier to just use \dots and not have to remember the details. but if the alternative chosen by amsmath isn't appropriate, the original commands can still be used explicitly.

ᴇɴᴅᴇʀᴍᴀɴ
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barbara beeton
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    Thank you very much. :) I'm curious: Where or how to learn these things in the first place? – Foo Bar Oct 15 '12 at 15:16
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    @FooBar texdoc source2e is a good starting point :) – cmhughes Oct 15 '12 at 16:16
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    @FooBar and for the ams \dots see texdoc amsmath, of course. – Andrew Swann Jan 18 '15 at 14:09
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    An example I just run into: I placed a \dots between two \cdot and promptly they landed on the same height as them. Methinks this looks awkward and I used \ldots, forcing them into basement. Your esthetic may vary. – Hauke Reddmann Oct 31 '17 at 10:38
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    @HaukeReddmann -- there are exceptions. this is one of them. it's always possible to override the amsmath decisions when necessary. – barbara beeton Oct 31 '17 at 14:27
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    @Enderman -- I didn't reject the edit, but there was a distinct reason for not capitalizing anything. At the time I wrote this answer, I was one of the TeX support staff at the American Math Society (AMS), and distinguished between "official" statements and ones that were my own opinion by capitalizing or not capitalizing. This answer was not approved by the AMS; it was based on my own knowledge. You have altered history. – barbara beeton Jul 06 '22 at 18:25
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    @barbarabeeton Oh, oops! Didn't realize that! Maybe put that comment in the answer? Sorry about that. – ᴇɴᴅᴇʀᴍᴀɴ Jul 06 '22 at 18:32
  • @barbarabeeton Just fixed it. – ᴇɴᴅᴇʀᴍᴀɴ Jul 06 '22 at 19:34
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    @Enderman -- Thanks. – barbara beeton Jul 06 '22 at 19:45