The java.lang.Math.expm1() returns ex -1. Note that for values of x near 0, the exact sum of expm1(x) + 1 is much closer to the true result of ex than exp(x).
- If the argument is NaN, the result is NaN.
- If the argument is positive infinity, then the result is positive infinity.
- If the argument is negative infinity, then the result is -1.0.
- If the argument is zero, then the result is a zero with the same sign as the argument.
Syntax:
public static double expm1(double x) Parameter: x-the exponent part which raises to e.
Returns:
The method returns the value ex-1, where e is the base of the natural logarithms.
Example : To show working of java.lang.Math.expm1() function
// Java program to demonstrate working // of java.lang.Math.expm1() method import java.lang.Math;
class Gfg {
// driver code
public static void main(String args[])
{
double x = 3 ;
// when both are not infinity
double result = Math.expm1(x);
System.out.println(result);
double positiveInfinity = Double.POSITIVE_INFINITY;
double negativeInfinity = Double.NEGATIVE_INFINITY;
double nan = Double.NaN;
// when x is NAN
result = Math.expm1(nan);
System.out.println(result);
// when argument is +INF
result = Math.expm1(positiveInfinity);
System.out.println(result);
// when argument is -INF
result = Math.expm1(negativeInfinity);
System.out.println(result);
x = - 0 ;
result = Math.expm1(x);
// same sign as 0
System.out.println(result);
}
} |
Output:
19.085536923187668 NaN Infinity -1.0 0.0