var float = 0.123456789;
var fixes = [1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000];
var fix = 2;
~~(float * fixes[fix]) / fixes[fix];
+(float.toFixed(fix))
~~(float * 100) / 2;
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Floar | |
toFixed | |
static mult |
Test name | Executions per second |
---|---|
Floar | 76444720.0 Ops/sec |
toFixed | 6450464.5 Ops/sec |
static mult | 386902176.0 Ops/sec |
Measuring JavaScript performance is crucial for developers to optimize their code. Let's break down the benchmark provided by MeasureThat.net.
Benchmark Overview
The test compares four approaches to round or format floating-point numbers:
Math.round()
toFixed(fix)
toPrecision(fix)
(note: this method was introduced in ECMAScript 2015, also known as ES6)~~(float * fixes[fix]) / fixes[fix]
)Options Compared
fix
decimal places.fix
significant digits (not necessarily decimal places).toFixed()
and can handle large numbers more efficiently. Cons: May not be suitable for all use cases, especially when dealing with decimal numbers.Library and Special JavaScript Features
None of the tested approaches use a dedicated library. However, toFixed()
and toPrecision()
rely on the Intl.NumberFormat API, which is available in modern browsers but not in older versions of Internet Explorer.
The "Floar" function uses bitwise operations, which are part of the ECMAScript standard. It's worth noting that this approach may not be suitable for all use cases due to its limited precision and potential for errors.
Other Alternatives
For rounding or formatting numbers, you can consider using other methods:
When choosing a method for rounding or formatting numbers, consider factors such as:
In this specific benchmark, the results suggest that toPrecision()
is likely the fastest approach due to its efficient use of binary representation. However, the choice of method ultimately depends on the specific requirements of your application.