distance¶

Editop¶

class rapidfuzz.distance.Editop(tag, src_pos, dest_pos)¶

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(editops=None, src_len=0, dest_len=0)¶

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(tag, src_start, src_end, dest_start, dest_end)¶

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(opcodes=None, src_len=0, dest_len=0)¶

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 Opcodes 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)]