ldexp, ldexpl
Remonter à Math.h - Index
Header File
math.h
Category
Math Routines
Prototype
double ldexp(double x, int exp);
long double ldexpl(long double x, int exp);
Description
Calculates x * 2^exp.
lexpl is the long double version; it takes a long double argument for x and returns a long double result.
Return Value
On success, ldexp (or ldexpl) returns the value it calculated, x * 2^exp. Error handling for these routines can be modified through the functions _matherr and _matherrl.
Example
#include <stdio.h>
#include <math.h>
int main(void)
{
double value;
double x = 2;
/* ldexp raises 2 by a power of 3
then multiplies the result by 2 */
value = ldexp(x,3);
printf("The ldexp value is: %lf\n", value);
return 0;
}
Portability
POSIX | Win32 | ANSI C | ANSI C++ | |
---|---|---|---|---|
ldexp |
+ |
+ |
+ |
+ |
ldexpl |
+ |
+ |
+ |