FREXP(S) XENIX System V FREXP(S)
Name
frexp, ldexp, modf - Splits floating-point number into a
mantissa and an exponent.
Syntax
double frexp (value, eptr)
double value;
int *eptr;
double ldexp (value, exp)
double value;
int exp;
double modf (value, iptr)
double value, *iptr;
Description
Every non-zero number can be written uniquely as x * 211
wher the ``mantissa'' (fraction) x is in the range 0.5 _ | x
< 1.0 and the ``exponent'' n is an integer. frexp returns
the mantissa of a double value and stores the exponent
indirectly in the location pointed to by exptr. If value is
0, both results returned by frexp are 0.
ldexp returns the quantity value*(2**exp).
modf returns the positive fractional part of value and
stores the integer part indirectly through iptr.
Diagnostics
If ldexp would cause overflow, _ HUGE is returned (according
to the sign of value), and errno is set to ERANGE.
If ldexp would cause underflow, zero is returned and errno
is set to ERANGE.
Notes
These routines must be linked by using the -lm linker
option.
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