The syntax of the Math.fround()
function is:
Math.fround(doubleFloat)
fround()
, being a static method, is called using the Math
class name.
Math.fround() Parameters
The Math.fround()
function takes in:
- doubleFloat - A
Number
.
Return value from Math.fround()
- Returns the nearest 32-bit single precision float representation of the given number.
- Returns
NaN
if non-numeric argument.
Example: Using Math.fround()
var num = Math.fround(1.5);
console.log(num); // 1.5
var num = Math.fround(5.05);
console.log(num); // 5.050000190734863
console.log(2 ** 130); // 1.361129467683754e+39
var num = Math.fround(2 ** 130);
console.log(num); // Infinity
var num = Math.fround(5);
console.log(num); // 5
var num = Math.fround(1.337);
console.log(num); // 1.3370000123977661
Output
1.5 5.050000190734863 1.361129467683754e+39 Infinity 5 1.3370000123977661
JavaScript uses 64-bit double floating-point numbers internally.
Here, 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.
SInce 2**130 is too big for a 32-bit float, fround()
returns Infinity
for such numbers.
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