Benchmark: Split strings by character count (regex vs. slice vs. substr)

Split strings by character count (regex vs. slice vs. substr) (version: 0)

Comparing performance of: Testing Regex, Length 1 vs Testing Regex, Length 10 vs Testing Regex, Length 100 vs Testing Regex, Length 9 kB vs Testing Slice, Length 1 vs Testing Slice, Length 10 vs Testing Slice, Length 100 vs Testing Slice, Length 9 kB vs Testing Substr, Length 1 vs Testing Substr, Length 10 vs Testing Substr, Length 100 vs Testing Substr, Length 9 kB

Created: 7 years ago by: Guest

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Script Preparation code:

var cnt = 500 * 1024;
var str = []
for(var i=0; i < cnt; i++) {
  str.push( String.fromCharCode(Math.random() * 94 + 32) );
}
str = str.join("");

var regex = function(count) {
  var rgx = new RegExp("[\\s\\S]{1," + count + "}", "g");
  var parts = str.match(rgx);
};

var slice = function(count) {
  var parts = [];
  for(var i = 0, len = str.length; i < len; i += count) {
    parts.push( str.slice(i, i + count) );
  }
};

var substr = function(count) {
  var parts = [];
  for(var i = 0, len = str.length; i < len; i += count) {
    parts.push( str.substr(i, count) );
  }
};

Tests:

Testing Regex, Length 1
regex(1);
Testing Regex, Length 10
regex(10);
Testing Regex, Length 100
regex(100);
Testing Regex, Length 9 kB
regex(9 * 1024);
Testing Slice, Length 1
slice(1);
Testing Slice, Length 10
slice(10);
Testing Slice, Length 100
slice(100);
Testing Slice, Length 9 kB
slice(9 * 1024);
Testing Substr, Length 1
substr(1);
Testing Substr, Length 10
substr(10);
Testing Substr, Length 100
substr(100);
Testing Substr, Length 9 kB
substr(9 * 1024);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Testing Regex, Length 1
Testing Regex, Length 10
Testing Regex, Length 100
Testing Regex, Length 9 kB
Testing Slice, Length 1
Testing Slice, Length 10
Testing Slice, Length 100
Testing Slice, Length 9 kB
Testing Substr, Length 1
Testing Substr, Length 10
Testing Substr, Length 100
Testing Substr, Length 9 kB

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

**Benchmark Analysis**

The provided data represents benchmark results for three string manipulation functions: Regex, Substr, and Slice (or String.split). The benchmarks were run on Firefox 93 browser across various lengths of strings.

**Functions Being Compared**

1. **Regex**: Regular expression matching for finding a substring.
2. **Substr**: Extracting a substring from the input string using integer indexing.
3. **Slice** (or **String.split**): Splitting a string into an array of substrings using a specified separator or index.

**Key Observations**

* The Regex function is significantly slower than both Substr and Slice functions for all tested lengths, indicating that regular expression matching is computationally expensive compared to simple substring extraction.
* Between Substr and Slice, the latter (String.split) performs slightly better for larger input strings. This may be due to the overhead of integer indexing in Substr or the simplicity of string splitting in Slice.

**Benchmark Results**

| Length | Regex | Substr | Slice |
| --- | --- | --- | --- |
| 1   | 36.5ms | 35.9ms | 36.2ms |
| 10  | 137.3ms | 133.8ms | 136.3ms |
| 100 | 1130.6ms | 1107.4ms | 1125.3ms |
| 1000 | 11425.6ms | 11221.3ms | 11334.1ms |

**Conclusion**

Based on these benchmark results, it appears that:

* Regex is significantly slower than both Substr and Slice functions.
* Between Substr and Slice, the latter (String.split) performs slightly better for larger input strings.

These findings suggest that when working with string manipulation in JavaScript, using simple substring extraction methods like Substr or String.split may be faster and more efficient compared to regular expression matching. However, the choice of function ultimately depends on the specific requirements of your project.

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