Standard library header <cfloat>
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                    This header was originally in the C standard library as <float.h>.
This header is part of the type support library, in particular it's part of the C numeric limits interface.
[edit] Macros
| the radix (integer base) used by the representation of all three floating-point types (macro constant) | |
| number of decimal digits that can be converted to long double and back without losing precision (macro constant) | |
| minimum positive value of float, double and long double respectively (macro constant) | |
| maximum value of float, double and long double respectively (macro constant) | |
| difference between 1.0 and the next representable value for float, double and long double respectively (macro constant) | |
| number of decimal digits that can be represented without losing precision for float, double and long double respectively (macro constant) | |
| number of base FLT_RADIXdigits that can be represented without losing precision for float, double and long double respectively(macro constant) | |
| minimum negative integer such that FLT_RADIXraised by power one less than that integer is a normalized float, double and long double respectively(macro constant) | |
| minimum negative integer such that 10 raised by power one less than that integer is a normalized float, double and long double respectively (macro constant) | |
| maximum positive integer such that FLT_RADIXraised by power one more than that integer is a normalized float, double and long double respectively(macro constant) | |
| maximum positive integer such that 10 raised by power one more than that integer is a normalized float, double and long double respectively (macro constant) | |
| default rounding mode of floating-point arithmetics (macro constant) | |
| (C++11) | specifies in what precision all arithmetic operations are done (macro constant) |