frexp, frexpf, frexpl - extract mantissa and exponent from double precision number

Syntax	#include <math.h> double frexp(double num, int *exp); C11 float frexpf(float num, int *exp); long double frexpl(long double num, int *exp); (End)
Description	These functions split a floating-point value num into the mantissa x and the exponent exp using the formula: num = x * 2exp |x| is in the interval [0.5, 1.0] exp is a pointer to an integer that specifies the exponent to the base 2. frexp() is the inverse function of ldexp().
Return val.	Mantissa x	a floating-point number of the function-type that lies in the interval [0.5, 1.0] and satisfies the equation: num = x * 2exp. The exponent is stored in exp.
	0	if num is equal to 0 (in which case the exponent is also equal to 0).
Notes	An application wishing to check for error situations should set errno to 0 before calling frexp(). If errno is set on return, an error has occurred.
See also	ldexp(), modf(), math.h.