30 Localization library [localization]

30.4 Standard locale categories [locale.categories]

30.4.3 The numeric category [category.numeric]

30.4.3.3 Class template num_put [locale.nm.put]

30.4.3.3.3 Virtual functions [facet.num.put.virtuals]

Table 111: Floating-point conversions [tab:facet.num.put.fp]
State
stdio equivalent
floatfield == ios_base​::​fixed
%f
floatfield == ios_base​::​scientific && !uppercase
%e
floatfield == ios_base​::​scientific
%E
floatfield == (ios_base​::​fixed | ios_base​::​scientific) && !uppercase
%a
floatfield == (ios_base​::​fixed | ios_base​::​scientific)
%A
!uppercase
%g
otherwise
%G