The Math.log2()
static method returns the base 2 logarithm of a number. That is
βx>0,πΌπππ.ππππΈ(π‘)=log2(x)=the unique y such that 2y=x\forall x > 0,\;\mathtt{\operatorname{Math.log2}(x)} = \log_2(x) = \text{the unique } y \text{ such that } 2y = x
Syntax
Math.log2(x)
Parameters
x
- : A number greater than or equal to 0.
Return value
The base 2 logarithm of x
. If x < 0
, returns NaN.
Description
Because log2()
is a static method of Math
, you always use it as Math.log2()
, rather than as a method of a Math
object you created (Math
is not a constructor).
This function is the equivalent of Math.log(x) / Math.log(2)
. For log2(e)
, use the constant Math.LOG2E, which is 1 / Math.LN2.
Examples
Using Math.log2()
Math.log2(-2); // NaN
Math.log2(-0); // -Infinity
Math.log2(0); // -Infinity
Math.log2(1); // 0
Math.log2(2); // 1
Math.log2(3); // 1.584962500721156
Math.log2(1024); // 10
Math.log2(Infinity); // Infinity