Editing Decimal separator (section)

===Constructed languages===
The three most spoken [[international auxiliary language]]s, [[Ido]], [[Esperanto]], and [[Interlingua]], all use the comma as the decimal separator.

Interlingua has used the comma as its decimal separator since the publication of the [[Interlingua: A Grammar of the International Language|Interlingua Grammar]] in 1951.<ref>{{cite web |series=Grammar of Interlingua |title=Parts of Speech – Numerals |url=http://members.optus.net/~ado_hall/interlingua/gi/parts_of_speech/numerals.html |access-date=2008-03-18 |url-status=dead |archive-url=http://arquivo.pt/wayback/20160516201404/http://members.optus.net/~ado_hall/interlingua/gi/parts_of_speech/numerals.html |archive-date=2016-05-16}}</ref>

Esperanto also uses the comma as its official decimal separator, whilst thousands are usually separated by [[non-breaking space]]s (e.g. {{nobr|12 345 678,9}}). It is possible to separate thousands by a [[full stop]] (e.g. {{nobr|12.345.678,9}}), though this is not as common.<ref>{{cite book |last1=Wennergren |first1=Bertilo |title=Plena Manlibro de Esperanta Gramatiko |trans-title=Complete Manual of Esperanto Grammar |chapter=Helposignoj |trans-chapter=Helping Symbols |edition=15.4 |url=https://bertilow.com/pmeg/ |chapter-url=https://bertilow.com/pmeg/skribo_elparolo/skribo/helposignoj.html |date=5 July 2023 |lang=Esperanto}}</ref>

Ido's ''Kompleta Gramatiko Detaloza di la Linguo Internaciona Ido'' (Complete Detailed Grammar of the International Language Ido) officially states that commas are used for the decimal separator whilst full stops are used to separate thousands, millions, etc. So the number 12,345,678.90123 (in American notation), for instance, would be written ''12.345.678,90123'' in Ido.

The 1931 grammar of [[Volapük]] uses the comma as its decimal separator but, somewhat unusually, the middle dot as its thousands separator (12·345·678,90123).<ref>{{cite book |author=de&nbsp;Jong, Arie |author-link=Arie de Jong |year=2012 |title=Gramat Volapüka. Cathair na Mart |editor=Everson, Michael |publisher=Evertype |isbn=978-1-904808-94-7 |url=http://evertype.com/books/dejong-gramat.html}}</ref>

In 1958, disputes between European and American delegates over the correct representation of the decimal separator nearly stalled the development of the [[ALGOL]] computer programming language.<ref>Perlis, Alan, ''The American Side of the Development of ALGOL'', ACM SIGPLAN Notices, August 1978.</ref> ALGOL ended up allowing different decimal separators, but most computer languages and standard data formats (e.g., [[C (programming language)|C]], [[Java (programming language)|Java]], [[Fortran]], [[CSS|Cascading Style Sheets (CSS)]]) specify a dot. [[C++14#Digit_separators|C++]] and a couple of others permit a quote (') as thousands separator, and many others like Python and Julia, (only) allow '_' as such a separator (it's usually ignored, i.e. also allows 1_00_00_000 aligning with the Indian number style of 1,00,00,000 that would be 10,000,000 in the US).