Format
#include <math.h> double ldexp(double x, int exp);
Language Level: ANSI
Threadsafe: Yes.
Description
The ldexp() function calculates the value of x * (2exp).
Return Value
The ldexp() function returns the value of x*(2exp). If an overflow results, the function returns +HUGE_VAL for a large result or -HUGE_VAL for a small result, and sets errno to ERANGE.
Example that uses ldexp()
This example computes y as 1.5 times 2 to the fifth power (1.5*25):
#include <math.h> #include <stdio.h> int main(void) { double x, y; int p; x = 1.5; p = 5; y = ldexp(x,p); printf("%lf times 2 to the power of %d is %lf\n", x, p, y); } /******************** Output should be similar to: ************** 1.500000 times 2 to the power of 5 is 48.000000 */
Related Information
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