LEVENSHTEIN With Modifier (TOLERANCE) - trillium_discovery - trillium_quality - Latest

Trillium Control Center

Product type
Software
Portfolio
Verify
Product family
Trillium
Product
Trillium > Trillium Discovery
Version
Latest
Language
English
Product name
Trillium Quality and Discovery
Title
Trillium Control Center
Copyright
2024
First publish date
2008
Last updated
2024-10-18
Published on
2024-10-18T15:02:04.502478

The TOLERANCE modifier is used with the LEVENSHTEIN routine to set the maximum number of edit distance allowed for specified length of strings. If the number of distance exceeds the value set by the modifier, the Nomatch score (2) is returned.

Syntax

TOLERANCE (n1,n2, n3,...,n10

where

  • The values (n1-n10) are comma delimited and their position in the parenthesis represent the maximum number of edit distance allowed in the string. n1 represents an edit distance of 1, n2 represents an edit distance of 2 and so on. You can set a maximum of 10 values.
  • Each n value specifies the maximum length of strings. The maximum length is based on the field length of the first record (String 1).

Example 1

TOLERANCE(,,8)

This indicates the following:

  • No tolerance string length is set for an edit distance of 1 and 2.
  • For String 1 with a length less than or equal to 8, edit distance must be 3 or less, otherwise Nomatch (2) is returned.

String 1 - ISABELLA

String 2 - ISAVEL

In this case, the length of String 1 is 8 and the edit distance is 3, one substitution ('V' for 'B') and two insertions ('L' and 'A'), therefore the result is valid and the score 99-3=96 is returned.

Example 2

TOLERANCE(,5,8,12)

This example indicates the following:

  • No tolerance string length is set for an edit distance of 1.
  • For String 1 with a length less than or equal to 5, edit distance must be 2 or less, otherwise Nomatch (2) is returned.
  • For String 1 with a length greater than 5 but less than or equal to 8, edit distance must be 3 or less, otherwise Nomatch (2) is returned.
  • For String 1 with a length greater than 8 but less than or equal to 12, edit distance must be 4 or less, otherwise Nomatch (2) is returned.
  • For String 1 with a length greater than 12, edit distance of 5 or more is returned.

String 1 - William J

String 2 - Willy

In this case, the length of String 1 is 9 and the edit distance is 5, one substitution ('y' for 'i') and four insertions ('a', 'm', space, and 'J'). When the length of String 1 is greater than 8 but less than or equal to 12, edit distance must be 4 or less, therefore the result is invalid and Nomatch score of 2 is returned.