What Is the Comma in a Number Called

2 Answers 2

The following sentence is a professional request:

Please use delimiters with large numbers.

A delimiter is a sequence of one or more characters used to specify the boundary between separate, independent regions in plain text or other data streams.

Delimiters are particularly helpful in mathematical notation:

For ease of reading, numbers with many digits may be divided into groups using a delimiter.

Source: en.wikipedia.org Emphasis mine

answered Apr 1 '15 at 23:07

ScotMScotM

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No: paired quotes, parenthesess, and brackets are delimiters; commas and semicolons are separators; and periods (full stops), question marks, and exclamation points are terminators. See the differences now?

Apr 2 '15 at 1:06
Yes, @tchrist, I appreciate this fine distinction of punctuation in English composition, but in mathematical notation (and many cases of data management), delimiters are employed one at a time. The preponderance of definitions, including the two I cited, allow for the solitary delimiter.

Apr 2 '15 at 14:25
Not when people are being careful about it, it doesn't. The string ":a:b:c:" has 5 colon-separated fields, 3 colon-delimited fields, and 4 colon-terminated fields. These are utterly different. I don't want anybody who believes that 3 = 4 = 5 anywhere near my data, because they'll just screw it up with their carelessness. Every single technical specification makes clear which of those MUST be used. Only vague hand-waving talk by people who have no idea what they are actually talking about ever equates those. You cannot do real technical work with such silliness—because it is unprofessional.

Apr 2 '15 at 15:06
Agreed, @tchrist, in some situations the fine distinction is important :-)

Apr 2 '15 at 15:15
I ended up using the verbiage "correctly delimited numbers" as I was trying to describe numbers that are separated by thousands (or whichever separation your language uses) as a blanket term.

Apr 2 '15 at 15:21

Commonly "thousands separator" is the name of the comma in this format; that doesn't translate nicely to an adjective, so perhaps you could rephrase your statement slightly to tell them to use "numbers with thousands separators" (rather than the clumsy "thousands separated numbers").

answered Apr 1 '15 at 23:06

smathysmathy

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Note that this is probably only true in locales that use delimiters to indicate thousands; not all of them do. For example, in India, five digit numbers and larger are grouped by digit pairs rather than triples. I'm not sure what they would be called there, but it seems likely that they aren't "thousands separators".

Apr 2 '15 at 0:51
@Mark Those ARE NOT delimiters. Those are separators, as this answer properly calls them.

Apr 2 '15 at 1:07
Ummm... OK. They're still likely not called thousands separators. Since, y'know, they're not thousands.

Apr 2 '15 at 7:38
Whether they're used or not is obviously locale-specific, the name of them is not. Even in India, if you were describing the commas that other locales use to separate the thousands, then the commonly used term is as I describe in my answer.

Apr 3 '15 at 23:22