The standard C library has 4 floating point rounding modes available through
cfenv.h. These are now available in C++11 through the header file
FE_TONEAREST FE_DOWNWARD FE_UPWARD FE_TOWARDZERO
FE_TONEARESTrounds to the nearest integer. If the floating point value is exactly midway between two integers, then it does round half to even. This rounding mode is also called round-to-nearest-even (RNE). The rest of the rounding modes are self explanatory.
#define FE_TONEAREST 0x000 #define FE_DOWNWARD 0x400 #define FE_UPWARD 0x800 #define FE_TOWARDZERO 0xC00
FE_TONEARESTwas the default rounding mode when I used methods like
nearbyintto perform rounding.