Convert spreadsheet decimal number format: period- and comma-separated decimal positions

Question

In OpenOffice Calc, one can change number format between standard United States, with decimal separator being a period ., and the SI (International System) format with decimal separator being a comma ,. This can be done by setting the language to US-English in the first case, and to Canada-French in the latter case (in the Format menu).

    13.3        13,3
    2.2         2,2

How can the same be done in Google Spreadsheets?
It does not seem that language can be changed within a same sheet (or maybe a same Google account ...?).
Is there another way?

Copy-paste from OO to Google does not work:

    13/03/2014      13,3
    02/02/2014      2,2

Answer 1

I dispute that comma as the decimal separator is " the SI (International System) format " - rather than one of ;-) - but think what you want is:

File > Spreadsheet settings ... and for Locale: choose somewhere like Canada (French).

Though beware, this could have ramifications beyond , for ..

Answer 2

The 22nd General Conference on Weights and Measures declared in 2003 that "the symbol for the decimal marker shall be either the point on the line or the comma on the line". It further reaffirmed that "numbers may be divided in groups of three in order to facilitate reading; neither dots nor commas are ever inserted in the spaces between groups"[20] (e.g. 1000000000). This usage has therefore been recommended by technical organizations, such as the United States' National Institute of Standards and Technology.[21]

ISO-8601 also stipulates normative notation based on SI conventions, adding that the comma is preferred over the full stop.