The Math.fround() method returns the nearest 32-bit single precision float representation of a number.
Example
// calculate the nearest 32-bit single
// precision float representation of 5.05
var num = Math.fround(5.05);
console.log(num);
// Output: 5.050000190734863
fround() Syntax
The syntax of the fround() method is:
Math.fround(doubleFloat)
Here, fround() is a static method. Hence, we need to access the method using the class name, Math.
fround() Parameters
The fround() method takes in:
- doubleFloat - a number.
fround() Return Value
The fround() method returns:
- the nearest 32-bit single precision float representation of the given number.
NaNfor non-numeric arguments.
Example 1: JavaScript Math.fround()
// find the nearest 32-bit single precision float representation of 1.5
var num1 = Math.fround(1.5);
console.log(num1);
// find the nearest 32-bit single precision float representation of 1.337
var num2 = Math.fround(1.337);
console.log(num2);
Output
1.5 1.3370000123977661
In the above example,
Math.fround(1.5)computes the nearest 32-bit single precision float representation of 1.5Math.fround(1.337)computes the nearest 32-bit single precision float representation of 1.337
Note: JavaScript uses 64-bit double floating-point numbers internally.
In the example above, we can see that the numbers that can be represented perfectly in the binary numeral system (like 1.5) have the same 32-bit single precision float representation.
However, some that can't be represented perfectly (like 1.337 or 5.05) differ in 32-bit and 64-bit.
Example 2: fround() With Large Numbers
// find the nearest 32-bit single precision float representation of 2 ** 130
var num = Math.fround(2 ** 130);
console.log(num);
// Output: Infinity
In the above example, we have used Math.fround() to compute the nearest 32-bit single precision float representation for an extremely large number: 2 ** 130 which is 1.361129467683754e+39.
The output indicates that the result is Infinity for extremely large numbers.
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