The information in this document refers to functions that are available in the latest version of the RML Mapper feature.
Lenses may require updating in order to take advantage of any newly created functions.

General Functionality

A triple will not be generated if the subject or object is provided will a NULL value.
Strings passed into functions may be sourced from
- References (The entire value of a field in the source document)
- Templates (A string that includes values of fields in the source document, as well as manually specified strings)
- Outputs from other Functions (Functions may therefore be nested)

Prefixes

In order to make use of the below functions, you must include the following prefixes in your mapping files:

@prefix fnml: <http://semweb.mmlab.be/ns/fnml#> .
@prefix fno: <https://w3id.org/function/ontology#> .
@prefix grel: <http://users.ugent.be/~bjdmeest/function/grel.ttl#> .

Custom Data Lens Functions

removeEqualValues

Description: Returns NULL if Input is equal to any of the values in String1
Use Case: Don’t generate a triple if the value in the source data is ‘None’ or N/A
Required Parameters:
- Input - Input text
- String1 - Delimited list of values
Returns: Input or NULL

fnml:functionValue [                                      # The object is the result of the function
        rr:predicateObjectMap [
          rr:predicate fno:executes ;                           # Execute the function
          rr:objectMap [ rr:constant grel:removeEqualValues ]   # The name of the function
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;                    # Expected input type
          rr:objectMap [ rr:template "{Name}" ]                 # Input value param, referenced from the data source
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;                   # Expected input type
          rr:objectMap [ rr:constant "null,\N" ]                # Input value param, string constant as defined in ""
        ]
      ]

findAndReplace

Description: Find part or all of the first input value from a list of regex, provided by the second input of comma separated values, and replace with its respective value from the third input of comma separated values
Use Case: Remove undesirable values from within field data.
Expects:
- Input - Input text
- String1 - Regex find values
- String2 - Regex replace values
Returns: Input, where matched values from String1 are replaced with corresponding values from String2

fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:findAndReplace ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [ rr:template "{Name}" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;
          rr:objectMap [ rr:constant "Bert,\],Venus,%20" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter3 ;
          rr:objectMap [ rr:constant "Bret,,Pluto, " ]
        ]
      ]

removeAllDoubleQuotes

Description: Returns the input with all double quotes removed
Use Case: Remove unnecessary double quotation marks from within field data.
Expects:
- Input- Input text
Returns: Input with all double quotation marks have been removed.

fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:removeAllDoubleQuotes ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [ rr:template "{Name}" ]
        ]
      ]

translateToISODate

Description: Allows valid xsd:date values to be generated from non ISO standard date formats.
Use Case: The source data provides a date, but it’s not in xsd:date format.
Expects:
- YearString - Delimited list containing
  - Input - Input text
  - StartPosition - Which position to start from, relative to the beginning on the Input text
  - CharacterCount - Number of characters after the StartPosition to extract
  - Prefix -2 digit prefix to add to extracted 2 character date, to make a 4 character date.
- MonthString - Delimited list containing
  - Input - Input text
  - StartPosition - Which position to start from, relative to the beginning on the Input text
  - CharacterCount - Number of characters after the StartPosition to extract
- DayString - Delimited list containing
  - Input - Input text
  - StartPosition - Which position to start from, relative to the beginning on the Input text
  - CharacterCount - Number of characters after the StartPosition to extract
Returns: Date in the format YYYY-MM-DD

 fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:translateToISODate ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [
            rr:template "{Date},6,4,";
      	    rr:termType rr:Literal;
          ];
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;
          rr:objectMap [
            rr:template "{Date},3,2";
            rr:termType rr:Literal;
          ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter3 ;
          rr:objectMap [
            rr:template "{Date},0,2,";
            rr:termType rr:Literal;
          ]
        ]
      ];
      rr:datatype xsd:date;
      rr:termType rr:Literal;

extractCharactersFromEnd

Description: Extract a configurable number of characters from within a provided string, relative to the end of the string.
Use Case: You only want the last 5 characters from a provided string.
Expects:
- Input - Input text
- String1 - Which position to start from, relative to the end on the Input text (0 being the last character)
- String2 - Number of characters prior to the position in String1 to extract
Returns: A slice of characters from the input text or NULL

fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:extractCharactersFromEnd ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [ rr:template "{Name}" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;
          rr:objectMap [ rr:constant "0" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter3 ;
          rr:objectMap [ rr:constant "5" ]
        ]
      ]

extractCharactersFromStart

Description: Extract a configurable number of characters from within a provided string, relative to the beginning of the string.
Use Case: You only want the first 5 characters from a provided string.
Expects:
- Input - Input text
- String1 - Which position to start from, relative to the beginning of the Input text (0 being the first character)
- String2 - Number of characters after the position in String1 to extract
Returns: A slice of characters from the input text or NULL

fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:extractCharactersFromStart ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [ rr:template "{Name}" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;
          rr:objectMap [ rr:constant "0" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter3 ;
          rr:objectMap [ rr:constant "5" ]
        ]
      ]

retrieveValueFromDelimitedList

Description: Extracts a specified value from a provided delimited list.
Use Case:
Expects:
- Input - Input delimited list
- String1 - Value used as the delimiter
- String2 - Which element from the delimited list to return
Returns: An element extract from the Input list, or NULL

 fnml:functionValue [
        rr:predicateObjectMap [
          rr:predicate fno:executes ;
          rr:objectMap [ rr:constant grel:retrieveValueFromDelimitedList ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter ;
          rr:objectMap [ rr:template "{Name}" ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter2 ;
          rr:objectMap [ rr:constant "," ]
        ] ;
        rr:predicateObjectMap [
          rr:predicate grel:valueParameter3 ;
          rr:objectMap [ rr:constant "1" ]
        ]
      ]

toUpperCase

Description: Converts a provided string to UPPERCASE
Use Case:
Expects:
- Input
Returns: Input, in UPPERCASE

fnml:functionValue [
      rr:predicateObjectMap [
        rr:predicate fno:executes ;
        rr:objectMap [ rr:constant grel:toUpperCase ]
      ] ;
      rr:predicateObjectMap [
        rr:predicate grel:valueParameter ;
        rr:objectMap [ rr:template "{Name}" ]
      ]
    ]

toLowerCase

Description: Converts a provided string to lowercase
Use Case:
Expects:
- Input
Returns: Input, in lowercase

fnml:functionValue [
      rr:predicateObjectMap [
        rr:predicate fno:executes ;
        rr:objectMap [ rr:constant grel:toLowerCase ]
      ] ;
      rr:predicateObjectMap [
        rr:predicate grel:valueParameter ;
        rr:objectMap [ rr:template "{Name}" ]
      ]
    ]

concat

Description: Combines 2 provided strings, into 1 string
Use Case:
Expects:
- Input1
- Input2
Returns: Input1Input2

//This is unverified

fnml:functionValue [
      rr:predicateObjectMap [
        rr:predicate fno:executes ;
        rr:objectMap [ rr:constant grel:concat ]
      ] ;
      rr:predicateObjectMap [
        rr:predicate grel:valueParameter ;
        rr:objectMap [ rr:template "Part1" ]
      ] ;
      rr:predicateObjectMap [
        rr:predicate grel:valueParameter2 ;
        rr:objectMap [ rr:template "Part2" ]
      ]
    ]

random

Description: Returns a randomly generated UUID
Use Case:
Expects: None
Returns: A randomly generated UUID

//This is unverified

fnml:functionValue [
      rr:predicateObjectMap [
        rr:predicate fno:executes ;
        rr:objectMap [ rr:constant grel:random ]
      ] 
    ]

toUpperCaseURL

Description: Ensures that a provided string is a URL, and converts it to one if it isn’t (Prepends HTTP:// where necessary),
Use Case:
Expects:
- Input
Returns: Input1 in UPPERCASE converted to a URL

fnml:functionValue [
      rr:predicateObjectMap [
        rr:predicate fno:executes ;
        rr:objectMap [ rr:constant grel:toUpperCaseURL ]
      ] ;
      rr:predicateObjectMap [
        rr:predicate grel:valueParameter ;
        rr:objectMap [ rr:template "http://example.com/{Name}" ]
      ]
    ]

Default Mapper Functions

DBpedia Spotlight annotate

Returns the DBpedia URLs of the detected entities in the input text

Function IRI: http://example.com/idlab/function/dbpediaSpotlight

Label	IRI
input string	http://example.com/idlab/function/str
endpoint url string	http://example.com/idlab/function/endpoint

Read local file as string

Returns the content of a local file as string

Function IRI: http://example.com/idlab/function/readFile

Label	IRI
input path	http://example.com/idlab/function/path

True condition

Returns the value if the given boolean is true, else null

Function IRI: http://example.com/idlab/function/trueCondition

Label	IRI
boolean encoded as string	http://example.com/idlab/function/strBoolean
input string	http://example.com/idlab/function/str

and

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#boolean_and

Label	IRI
b	http://users.ugent.be/~bjdmeest/function/grel.ttl#param_rep_b

chomp

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_chomp

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sep	http://users.ugent.be/~bjdmeest/function/grel.ttl#p_string_sep

contains

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_contains

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sub	http://users.ugent.be/~bjdmeest/function/grel.ttl#string_sub

decide

Returns a given value if input is equal to another given value

Function IRI: http://example.com/idlab/function/decide

Label	IRI
input string	http://example.com/idlab/function/str
expected input string	http://example.com/idlab/function/expectedStr
result string	http://example.com/idlab/function/result

endsWith

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_endsWith

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sub	http://users.ugent.be/~bjdmeest/function/grel.ttl#string_sub

equal

Returns true if strings are equal.

Function IRI: http://example.com/idlab/function/equal

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
input value 2	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter2

escape

Escapes a string, with a mode parameter.

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#escape

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
mode value	http://users.ugent.be/~bjdmeest/function/grel.ttl#modeParameter

getMIMEType

Returns the MIME Type of a filename

Function IRI: http://example.com/idlab/function/getMIMEType

Label	IRI
input string	http://example.com/idlab/function/str

if

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#controls_if

Label	IRI
b	http://users.ugent.be/~bjdmeest/function/grel.ttl#bool_b
eTrue	http://users.ugent.be/~bjdmeest/function/grel.ttl#any_true
eFalse	http://users.ugent.be/~bjdmeest/function/grel.ttl#any_false

inRange

Returns whether a value is in range

Function IRI: http://example.com/idlab/function/inRange

Label	IRI
test	http://example.com/idlab/function/p_test
from	http://example.com/idlab/function/p_from
to	http://example.com/idlab/function/p_to

indexOf

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_indexOf

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sub	http://users.ugent.be/~bjdmeest/function/grel.ttl#string_sub

join

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#array_join

Label	IRI
a	http://users.ugent.be/~bjdmeest/function/grel.ttl#p_array_a
sep	http://users.ugent.be/~bjdmeest/function/grel.ttl#p_string_sep

length

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_length

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter

listContainsElement

Returns true if the string is found in the list

Function IRI: http://example.com/idlab/function/listContainsElement

Label	IRI
list	http://example.com/idlab/function/list
input string	http://example.com/idlab/function/str

mqlKeyUnquote

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_mqlKeyUnquote

Label	IRI
key	http://users.ugent.be/~bjdmeest/function/grel.ttl#p_key

not

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#boolean_not

Label	IRI
b	http://users.ugent.be/~bjdmeest/function/grel.ttl#bool_b

not equal

Returns true if strings are not equal.

Function IRI: http://example.com/idlab/function/notEqual

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
input value 2	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter2

or

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#boolean_or

Label	IRI
b	http://users.ugent.be/~bjdmeest/function/grel.ttl#param_rep_b

random

Returns a random uuid.

Function IRI: http://example.com/idlab/function/random

This function does not take any arguments.

split

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_split

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sep	http://users.ugent.be/~bjdmeest/function/grel.ttl#p_string_sep

startsWith

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_startsWith

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
sub	http://users.ugent.be/~bjdmeest/function/grel.ttl#string_sub

stringContainsOtherString

Returns true if a string is found in a delimited string.

Function IRI: http://example.com/idlab/function/stringContainsOtherString

Label	IRI
input string	http://example.com/idlab/function/str
other input string	http://example.com/idlab/function/otherStr
delimiter	http://example.com/idlab/function/delimiter

substring

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_substring

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter
from	http://users.ugent.be/~bjdmeest/function/grel.ttl#param_int_i_from
to	http://users.ugent.be/~bjdmeest/function/grel.ttl#param_int_i_opt_to

toLowercase

Returns the input with all letters in lower case.

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#toLowerCase

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter

toUppercase

Returns the input with all letters in upper case.

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#toUpperCase

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter

toTitlecase

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_toTitlecase

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter

toUpperCaseURL

Returns an uppercase, valid url.

Function IRI: http://example.com/idlab/function/toUpperCaseURL

Label	IRI
input string	http://example.com/idlab/function/str

trim

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#string_trim

Label	IRI
input value	http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter

xor

Function IRI: http://users.ugent.be/~bjdmeest/function/grel.ttl#boolean_xor

Label	IRI
b	http://users.ugent.be/~bjdmeest/function/grel.ttl#param_rep_b

List of Available Lens Functions

General Functionality

Prefixes

Custom Data Lens Functions

removeEqualValues

findAndReplace

removeAllDoubleQuotes

translateToISODate

extractCharactersFromEnd

extractCharactersFromStart

retrieveValueFromDelimitedList

toUpperCase

toLowerCase

concat

random

toUpperCaseURL

Default Mapper Functions

DBpedia Spotlight annotate

Read local file as string

True condition

and

chomp

contains

decide

endsWith

equal

escape

getMIMEType

if

inRange

indexOf

join

length

listContainsElement

mqlKeyUnquote

not

not equal

or

random

split

startsWith

stringContainsOtherString

substring

toLowercase

toUppercase

toTitlecase

toUpperCaseURL

trim

xor