Benchmark: toFixed vs toPrecision vs Math.round() vs Math.Floor

Script Preparation code:

var someFloat = 0.123456789;

Tests:

toFixed(6)
someFloat.toFixed(6);
toPrecision(6).toString()
someFloat.toPrecision(6);
(Math.round(*1000000)/1000000)
(Math.round(someFloat*1000000)/1000000);
Math.floor( * 1000000)
Math.floor(someFloat * 1000000);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toFixed(6)
toPrecision(6).toString()
(Math.round(*1000000)/1000000)
Math.floor( * 1000000)

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:127.0) Gecko/20100101 Firefox/127.0

Browser/OS: Firefox 127 on Windows

View result in a separate tab

Test name	Executions per second
toFixed(6)	23949510.0 Ops/sec
toPrecision(6).toString()	18116802.0 Ops/sec
(Math.round(*1000000)/1000000)	1782905216.0 Ops/sec
Math.floor( * 1000000)	1775076096.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark test cases.

**What is being tested?**

The provided JSON represents a benchmark test that compares four different approaches to round or limit the precision of a floating-point number in JavaScript:

1. `toFixed()`: rounds a number to a specified number of decimals.
2. `toPrecision()`: sets the number of significant digits in a number, which can be used to achieve similar rounding behavior as `toFixed()` but with more control over the formatting.
3. `Math.round()`: rounds a number to the nearest integer, which can be used to truncate or limit the precision of a number.
4. `Math.floor()`: truncates a number towards zero, effectively limiting its precision.

**Options compared**

The benchmark test cases compare these four options in different scenarios:

* In each test case, a floating-point number `someFloat` is defined using the provided JSON script preparation code (`var someFloat = 0.123456789;`).
* The different rounding approaches are then applied to `someFloat`, and the resulting values are measured.
* The benchmark measures the execution time for each approach.

**Pros and Cons of each approach:**

1. **toFixed(6)**:
	* Pros: easy to use, straightforward implementation.
	* Cons: can lead to rounding errors if not used carefully (e.g., due to precision issues).
2. **toPrecision(6).toString()**:
	* Pros: provides more control over formatting and can be used for precise arithmetic operations.
	* Cons: requires additional parsing of the resulting string, which may add overhead.
3. **Math.round(*1000000)/1000000**:
	* Pros: simple and efficient implementation.
	* Cons: relies on multiplication by a large constant factor (1000000), which can lead to precision issues if not used carefully.
4. **Math.floor(* 1000000)**:
	* Pros: easy to use, provides a clear limit on the number of digits.
	* Cons: truncates towards zero, effectively losing precision.

**Special JS features or syntax**

None of the test cases explicitly use special JavaScript features like async/await, promises, or modern ES6+ syntax. However, the `toPrecision()` method is used in conjunction with string parsing (`toString()`), which might be considered a slightly non-standard approach.

**Other alternatives**

If you want to explore alternative approaches, here are some options:

* Use a library like [decimal.js](https://mikulizer.github.io/decimal-js/) for precise arithmetic operations.
* Implement custom rounding functions using bitwise operators (e.g., `someFloat * 0x7fffffff` to achieve rounding towards zero).
* Compare the performance of other rounding approaches, such as `Number.EPSILON` or `Big.js`.
* Investigate how different browsers and environments handle these rounding approaches.

Please keep in mind that each approach has its trade-offs, and the best choice depends on your specific use case and requirements.

Related benchmarks:

toFixed vs toPrecision vs Math.round() vs Math.Floor (version: 0)

Comparing performance of: toFixed(6) vs toPrecision(6).toString() vs (Math.round(1000000)/1000000) vs Math.floor( 1000000)

Created: one year ago by: Guest

Jump to the latest result

toFixed(6)

toPrecision(6).toString()

(Math.round(*1000000)/1000000)

Math.floor( * 1000000)

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

toFixed vs toPrecision vs Math.round() vs Math.Floor (version: 0)

Comparing performance of: toFixed(6) vs toPrecision(6).toString() vs (Math.round(*1000000)/1000000) vs Math.floor( * 1000000)

Created: one year ago by: Guest

Jump to the latest result

toFixed(6)

toPrecision(6).toString()

(Math.round(*1000000)/1000000)

Math.floor( * 1000000)

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

Comparing performance of: toFixed(6) vs toPrecision(6).toString() vs (Math.round(1000000)/1000000) vs Math.floor( 1000000)