- Trang chủ
- Phát triển web
- PHP
- Hàm levenshtein[] trong PHP
Hướng dẫn cách sử dụng hàm levenshtein[] trong lập trình PHP
Tác dụng của hàm levenshtein[]
The levenshtein[]
function calculates Levenshtein distance between two strings.
The following table summarizes the technical details of this function.
Returns the Levenshtein-Distance between the two argument strings or -1, if one of the argument strings is longer than the limit of 255 characters. |
PHP 4.0.1+ |
Syntax
The basic syntax of the levenshtein[]
function is given with:
levenshtein[string1, string2, cost_insert, cost_replacement, cost_delete];
In its simplest form the function will take only the two strings as parameter and will calculate just the number of insert, replace and delete operations needed to transform string1 into string2.
The following example shows the levenshtein[]
function in action.
Example
Tip: The levenshtein[]
function is faster than the similar_text[]
function. However, similar_text[]
provides
better results with less modifications.
Note: The Levenshtein distance is defined as the minimum number of characters you have to replace, insert or delete to transform string1 into string2. The complexity of the algorithm is O[m*n]
, where n and m are the length of string1 and string2.
Parameters
The levenshtein[]
function accepts the following parameters.
string1 | Required. Specifies the first string being evaluated for Levenshtein distance. |
string2 | Required. Specifies the second string being evaluated for Levenshtein distance. |
cost_insert | Optional. Defines the cost of insertion. |
cost_replacement | Optional. Defines the cost of replacement. |
cost_delete | Optional. Defines the cost of deletion. |
More Examples
Here're some more examples showing how levenshtein[]
function actually works:
The following example demonstrates how to search for the closest match of a misspelled word inside an array of words. You can adjust the sensitivity of the result according to your need.
Example