distance¶

Editop¶

class rapidfuzz.distance.Editop¶

Tuple like object describing an edit operation. It is in the form (tag, src_pos, dest_pos)

The tags are strings, with these meanings:

tag	explanation
‘replace’	src[src_pos] should be replaced by dest[dest_pos]
‘delete’	src[src_pos] should be deleted
‘insert’	dest[dest_pos] should be inserted at src[src_pos]

Editops¶

class rapidfuzz.distance.Editops¶

List like object of Editops describing how to turn s1 into s2.

apply(source_string, destination_string)¶

apply editops to source_string

Parameters:

source_string (str | bytes) – string to apply editops to
destination_string (str | bytes) – string to use for replacements / insertions into source_string

Returns:

mod_string – modified source_string

Return type:

str

as_list()¶

Convert Editops to a list of tuples.

This is the equivalent of [x for x in editops]

as_matching_blocks()¶

Convert to matching blocks

Returns:: matching blocks – Editops converted to matching blocks
Return type:: list[MatchingBlock]

as_opcodes()¶

Convert to Opcodes

Returns:: opcodes – Editops converted to Opcodes
Return type:: Opcodes

copy()¶: performs copy of Editops

classmethod from_opcodes(opcodes)¶

Create Editops from Opcodes

Parameters:: opcodes (Opcodes) – opcodes to convert to editops
Returns:: editops – Opcodes converted to Editops
Return type:: Editops

inverse()¶

Invert Editops, so it describes how to transform the destination string to the source string.

Returns:: editops – inverted Editops
Return type:: Editops

Examples

>>> from rapidfuzz.distance import Levenshtein
>>> Levenshtein.editops('spam', 'park')
[Editop(tag=delete, src_pos=0, dest_pos=0),
 Editop(tag=replace, src_pos=3, dest_pos=2),
 Editop(tag=insert, src_pos=4, dest_pos=3)]

>>> Levenshtein.editops('spam', 'park').inverse()
[Editop(tag=insert, src_pos=0, dest_pos=0),
 Editop(tag=replace, src_pos=2, dest_pos=3),
 Editop(tag=delete, src_pos=3, dest_pos=4)]

remove_subsequence(subsequence)¶

remove a subsequence

Parameters:: subsequence (Editops) – subsequence to remove (has to be a subset of editops)
Returns:: sequence – a copy of the editops without the subsequence
Return type:: Editops

Opcode¶

class rapidfuzz.distance.Opcode¶

Tuple like object describing an edit operation. It is in the form (tag, src_start, src_end, dest_start, dest_end)

The tags are strings, with these meanings:

tag	explanation
‘replace’	src[src_start:src_end] should be replaced by dest[dest_start:dest_end]
‘delete’	src[src_start:src_end] should be deleted. Note that dest_start==dest_end in this case.
‘insert’	dest[dest_start:dest_end] should be inserted at src[src_start:src_start]. Note that src_start==src_end in this case.
‘equal’	src[src_start:src_end] == dest[dest_start:dest_end]

Note

Opcode is compatible with the tuples returned by difflib’s SequenceMatcher to make them interoperable

Opcodes¶

class rapidfuzz.distance.Opcodes¶

List like object of Opcodes describing how to turn s1 into s2. The first Opcode has src_start == dest_start == 0, and remaining tuples have src_start == the src_end from the tuple preceding it, and likewise for dest_start == the previous dest_end.

apply(source_string, destination_string)¶

apply opcodes to source_string

Parameters:

source_string (str | bytes) – string to apply opcodes to
destination_string (str | bytes) – string to use for replacements / insertions into source_string

Returns:

mod_string – modified source_string

Return type:

str

as_editops()¶

Convert to Editops

Returns:: editops – Opcodes converted to Editops
Return type:: Editops

as_list()¶

Convert Opcodes to a list of tuples, which is compatible with the opcodes of difflibs SequenceMatcher.

This is the equivalent of [x for x in opcodes]

as_matching_blocks()¶

Convert to matching blocks

Returns:: matching blocks – Opcodes converted to matching blocks
Return type:: list[MatchingBlock]

copy()¶: performs copy of Opcodes

classmethod from_editops(editops)¶

Create Opcodes from Editops

Parameters:: editops (Editops) – editops to convert to opcodes
Returns:: opcodes – Editops converted to Opcodes
Return type:: Opcodes

inverse()¶

Invert Opcodes, so it describes how to transform the destination string to the source string.

Returns:: opcodes – inverted Opcodes
Return type:: Opcodes

Examples

>>> from rapidfuzz.distance import Levenshtein
>>> Levenshtein.opcodes('spam', 'park')
[Opcode(tag=delete, src_start=0, src_end=1, dest_start=0, dest_end=0),
 Opcode(tag=equal, src_start=1, src_end=3, dest_start=0, dest_end=2),
 Opcode(tag=replace, src_start=3, src_end=4, dest_start=2, dest_end=3),
 Opcode(tag=insert, src_start=4, src_end=4, dest_start=3, dest_end=4)]

>>> Levenshtein.opcodes('spam', 'park').inverse()
[Opcode(tag=insert, src_start=0, src_end=0, dest_start=0, dest_end=1),
 Opcode(tag=equal, src_start=0, src_end=2, dest_start=1, dest_end=3),
 Opcode(tag=replace, src_start=2, src_end=3, dest_start=3, dest_end=4),
 Opcode(tag=delete, src_start=3, src_end=4, dest_start=4, dest_end=4)]