FREXP(3M) Mathematical Library Functions FREXP(3M)

# NAME

frexp, frexpf, frexpl - extract mantissa and exponent from a floating-point number

# SYNOPSIS

```c99 [ flag... ] file... -lm [ library... ]
#include <math.h>
double frexp(double num, int *exp);```

`float frexpf(float num, int *exp);`

`long double frexpl(long double num, int *exp);`

# DESCRIPTION

These functions break a floating-point number into a normalized fraction and an integral power of 2. They store the integer exponent in the int object pointed to by exp.

# RETURN VALUES

For finite arguments, these functions return the value x, such that x is a double with magnitude in the interval [½, 1) or 0, and num equals x times 2 raised to the power *exp.

If num is NaN, NaN is returned and the value of *exp is unspecified.

If num is ± 0, ± 0 is returned and the value of *exp is 0.

If num is ±Inf, num is returned and the value of *exp is unspecified.

# ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

 ATTRIBUTE TYPE ATTRIBUTE VALUE Interface Stability Standard MT-Level MT-Safe