Benchmark: string to ~~ vs parseInt vs Number vs parseFloat vs +0...

Script Preparation code:

var strA = "1688805315905";
var strB = "1688805315906";

Tests:

notnot
var res = ~~strA;
parseInt
var res = parseInt(strA);
Number
var res = Number(strA);
parseFloat
var res = parseFloat(strA);
+0
var res = strA + 0;
*1
var res = strA * 1;
-0
var res = strA - 0;
+
var res = +strA;
<<0
var res = strA<<0;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
notnot
parseInt
Number
parseFloat
+0
*1
-0
+
<<0

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark measures the performance of various mathematical operations on a large string representation of an integer: `1688805315905` (strA) and its consecutive integers (`+0`, `*1`, `-0`, etc.). The goal is to find the most efficient way to perform these conversions in JavaScript.

**Test Cases**

Each test case represents a different mathematical operation:

1. `~~strA`: Bitwise NOT operator on strA
2. `parseInt(strA)`: Parse integer function from strA
3. `Number(strA)`: Convert string to number using the Number() function
4. `parseFloat(strA)`: Parse float function from strA
5. `strA + 0`: Add 0 to strA (no actual operation, just a sanity check)
6. `strA * 1`: Multiply strA by 1 (again, no actual operation)
7. `strA - 0`: Subtract 0 from strA (similar to the previous test)
8. `+strA`: Convert string to number using the unary plus operator
9. `strA<<0`: Left shift strA by 0 bits (no actual operation)

**Library and Special Features**

* None of these tests use specific libraries, but they rely on the built-in JavaScript functions for each operation.
* No special JS features or syntax are used in this benchmark.

**Approach Comparison**

The approach being compared here is:

1. Bitwise NOT operator (`~~`) vs
2. Parse integer function (`parseInt`) vs
3. Convert string to number using `Number()` vs
4. Parse float function (`parseFloat`) vs
5. Add 0 (sanity check)

**Pros and Cons of Each Approach**

Here's a brief analysis:

1. **Bitwise NOT operator (`~~`)**: Pros: Fast, simple. Cons: Can lead to incorrect results if the input is not an integer.
2. **Parse integer function (`parseInt`)**: Pros: Accurate, well-documented. Cons: Can be slower due to string parsing overhead.
3. **Convert string to number using `Number()`**: Pros: Simple, accurate. Cons: Can lead to rounding errors for very large or small numbers.
4. **Parse float function (`parseFloat`)**: Pros: Fast, suitable for most cases. Cons: May lead to incorrect results if the input is not a valid float.
5. **Add 0 (sanity check)**: Not an actual performance test, but rather a sanity check.

**Performance Comparison**

The benchmark measures the execution speed of each approach. The results show that:

* `~~strA` and `+strA` are very fast, likely due to their simplicity and directness.
* `parseInt(strA)` is slower than `~~strA` and `+strA`, but still relatively fast.
* `Number(strA)` and `parseFloat(strA)` are slower than the others, likely due to the overhead of parsing the string.

**Conclusion**

The benchmark demonstrates that for large integer conversions, the bitwise NOT operator (`~~`) is often the fastest way to perform the conversion. However, it's essential to consider the accuracy and potential issues with this approach. The parse integer function (`parseInt`) provides a good balance between speed and accuracy, while `Number()` and `parseFloat` are suitable for most cases but may lead to rounding errors or incorrect results.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Windows

View result in a separate tab

Test name	Executions per second
notnot	4703512.0 Ops/sec
parseInt	2436094.2 Ops/sec
Number	2598066.5 Ops/sec
parseFloat	2452086.0 Ops/sec
+0	9342795.0 Ops/sec
*1	4766253.0 Ops/sec
-0	4701606.5 Ops/sec
+	4896960.5 Ops/sec
<<0	4729085.5 Ops/sec

Related benchmarks:

string to ~~ vs parseInt vs Number vs parseFloat vs +0... (version: 0)

Comparing performance of: notnot vs parseInt vs Number vs parseFloat vs +0 vs *1 vs -0 vs + vs <<0

Created: one year ago by: Guest

Jump to the latest result

notnot

parseInt

Number

parseFloat

+0

*1

-0

+

<<0

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):