wordEncoding

Word encoding model to map words to indices and back

Description

A word encoding maps words in a vocabulary to numeric indices.

To encode documents as matrices of word or n-gram counts, use encode.

Creation

Syntax

enc = wordEncoding(documents)
enc = wordEncoding(documents,Name,Value)

Description

example

enc = wordEncoding(documents) creates a word encoding from the words in documents.

example

enc = wordEncoding(documents,Name,Value) specifies additional options using one or more name-value pair arguments. For example, 'Order','frequency' assigns lower indices to more frequent words.

Input Arguments

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Input documents, specified as a tokenizedDocument array.

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: 'Order','frequency' sorts the indices by the total frequency in the documents in descending order.

Sorting of indices, specified as the comma-separated pair consisting of 'Order' and one of the following:

  • 'first-seen' – Assign indices to the words in the order in which they occur in the documents.

  • 'frequency' – Assign indices to the words sorted by total frequency in the documents in descending order.

If 'Order' is 'frequency' and multiple words have the same frequency, then the function does not assign indices in any particular order.

Maximum number of words to encode, specified as a positive integer or Inf. The function first sorts the indices according to the 'Order' option and then encodes the top MaxNumWords words. If MaxNumWords is Inf, then the function encodes all the words in the input documents.

Properties

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Number of words in the model, specified as a nonnegative integer.

Unique words in the model, specified as a string vector.

Data Types: string

Object Functions

ind2wordMap encoding index to word
word2indMap word to encoding index
isVocabularyWordTest if word is member of word embedding or encoding

Examples

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Load the example data. The file sonnetsPreprocessed.txt contains preprocessed versions of Shakespeare's sonnets. The file contains one sonnet per line, with words separated by a space. Extract the text from sonnetsPreprocessed.txt, split the text into documents at newline characters, and then tokenize the documents.

filename = "sonnetsPreprocessed.txt";
str = extractFileText(filename);
textData = split(str,newline);
documents = tokenizedDocument(textData);
documents(1:10)
ans = 
  10x1 tokenizedDocument:

    70 tokens: fairest creatures desire increase thereby beautys rose might never die riper time decease tender heir might bear memory thou contracted thine own bright eyes feedst thy lights flame selfsubstantial fuel making famine abundance lies thy self thy foe thy sweet self cruel thou art worlds fresh ornament herald gaudy spring thine own bud buriest thy content tender churl makst waste niggarding pity world else glutton eat worlds due grave thee
    71 tokens: forty winters shall besiege thy brow dig deep trenches thy beautys field thy youths proud livery gazed tatterd weed small worth held asked thy beauty lies treasure thy lusty days say thine own deep sunken eyes alleating shame thriftless praise praise deservd thy beautys thou couldst answer fair child mine shall sum count make old excuse proving beauty succession thine new made thou art old thy blood warm thou feelst cold
    65 tokens: look thy glass tell face thou viewest time face form another whose fresh repair thou renewest thou dost beguile world unbless mother fair whose uneard womb disdains tillage thy husbandry fond tomb selflove stop posterity thou art thy mothers glass thee calls back lovely april prime thou windows thine age shalt despite wrinkles thy golden time thou live rememberd die single thine image dies thee
    71 tokens: unthrifty loveliness why dost thou spend upon thy self thy beautys legacy natures bequest gives nothing doth lend frank lends free beauteous niggard why dost thou abuse bounteous largess thee give profitless usurer why dost thou great sum sums yet canst live traffic thy self alone thou thy self thy sweet self dost deceive nature calls thee gone acceptable audit canst thou leave thy unused beauty tombed thee lives th executor
    61 tokens: hours gentle work frame lovely gaze every eye doth dwell play tyrants same unfair fairly doth excel neverresting time leads summer hideous winter confounds sap checked frost lusty leaves quite gone beauty oersnowed bareness every summers distillation left liquid prisoner pent walls glass beautys effect beauty bereft nor nor remembrance flowers distilld though winter meet leese show substance still lives sweet
    68 tokens: let winters ragged hand deface thee thy summer ere thou distilld make sweet vial treasure thou place beautys treasure ere selfkilld forbidden usury happies pay willing loan thats thy self breed another thee ten times happier ten ten times thy self happier thou art ten thine ten times refigurd thee death thou shouldst depart leaving thee living posterity selfwilld thou art fair deaths conquest make worms thine heir
    64 tokens: lo orient gracious light lifts up burning head eye doth homage newappearing sight serving looks sacred majesty climbd steepup heavenly hill resembling strong youth middle age yet mortal looks adore beauty still attending golden pilgrimage highmost pitch weary car like feeble age reeleth day eyes fore duteous converted low tract look another way thou thyself outgoing thy noon unlookd diest unless thou get son
    70 tokens: music hear why hearst thou music sadly sweets sweets war joy delights joy why lovst thou thou receivst gladly else receivst pleasure thine annoy true concord welltuned sounds unions married offend thine ear sweetly chide thee confounds singleness parts thou shouldst bear mark string sweet husband another strikes mutual ordering resembling sire child happy mother pleasing note sing whose speechless song many seeming sings thee thou single wilt prove none
    70 tokens: fear wet widows eye thou consumst thy self single life ah thou issueless shalt hap die world wail thee like makeless wife world thy widow still weep thou form thee hast left behind every private widow well keep childrens eyes husbands shape mind look unthrift world doth spend shifts place still world enjoys beautys waste hath world end kept unused user destroys love toward others bosom sits murdrous shame commits
    69 tokens: shame deny thou bearst love thy self art unprovident grant thou wilt thou art belovd many thou none lovst evident thou art possessd murderous hate gainst thy self thou stickst conspire seeking beauteous roof ruinate repair thy chief desire o change thy thought change mind shall hate fairer lodgd gentle love thy presence gracious kind thyself least kindhearted prove make thee another self love beauty still live thine thee

Create a word encoding.

enc = wordEncoding(documents)
enc = 
  wordEncoding with properties:

      NumWords: 3092
    Vocabulary: [1x3092 string]

Load the example data. The file sonnetsPreprocessed.txt contains preprocessed versions of Shakespeare's sonnets. The file contains one sonnet per line, with words separated by a space. Extract the text from sonnetsPreprocessed.txt, split the text into documents at newline characters, and then tokenize the documents.

filename = "sonnetsPreprocessed.txt";
str = extractFileText(filename);
textData = split(str,newline);
documents = tokenizedDocument(textData);
documents(1:10)
ans = 
  10x1 tokenizedDocument:

    70 tokens: fairest creatures desire increase thereby beautys rose might never die riper time decease tender heir might bear memory thou contracted thine own bright eyes feedst thy lights flame selfsubstantial fuel making famine abundance lies thy self thy foe thy sweet self cruel thou art worlds fresh ornament herald gaudy spring thine own bud buriest thy content tender churl makst waste niggarding pity world else glutton eat worlds due grave thee
    71 tokens: forty winters shall besiege thy brow dig deep trenches thy beautys field thy youths proud livery gazed tatterd weed small worth held asked thy beauty lies treasure thy lusty days say thine own deep sunken eyes alleating shame thriftless praise praise deservd thy beautys thou couldst answer fair child mine shall sum count make old excuse proving beauty succession thine new made thou art old thy blood warm thou feelst cold
    65 tokens: look thy glass tell face thou viewest time face form another whose fresh repair thou renewest thou dost beguile world unbless mother fair whose uneard womb disdains tillage thy husbandry fond tomb selflove stop posterity thou art thy mothers glass thee calls back lovely april prime thou windows thine age shalt despite wrinkles thy golden time thou live rememberd die single thine image dies thee
    71 tokens: unthrifty loveliness why dost thou spend upon thy self thy beautys legacy natures bequest gives nothing doth lend frank lends free beauteous niggard why dost thou abuse bounteous largess thee give profitless usurer why dost thou great sum sums yet canst live traffic thy self alone thou thy self thy sweet self dost deceive nature calls thee gone acceptable audit canst thou leave thy unused beauty tombed thee lives th executor
    61 tokens: hours gentle work frame lovely gaze every eye doth dwell play tyrants same unfair fairly doth excel neverresting time leads summer hideous winter confounds sap checked frost lusty leaves quite gone beauty oersnowed bareness every summers distillation left liquid prisoner pent walls glass beautys effect beauty bereft nor nor remembrance flowers distilld though winter meet leese show substance still lives sweet
    68 tokens: let winters ragged hand deface thee thy summer ere thou distilld make sweet vial treasure thou place beautys treasure ere selfkilld forbidden usury happies pay willing loan thats thy self breed another thee ten times happier ten ten times thy self happier thou art ten thine ten times refigurd thee death thou shouldst depart leaving thee living posterity selfwilld thou art fair deaths conquest make worms thine heir
    64 tokens: lo orient gracious light lifts up burning head eye doth homage newappearing sight serving looks sacred majesty climbd steepup heavenly hill resembling strong youth middle age yet mortal looks adore beauty still attending golden pilgrimage highmost pitch weary car like feeble age reeleth day eyes fore duteous converted low tract look another way thou thyself outgoing thy noon unlookd diest unless thou get son
    70 tokens: music hear why hearst thou music sadly sweets sweets war joy delights joy why lovst thou thou receivst gladly else receivst pleasure thine annoy true concord welltuned sounds unions married offend thine ear sweetly chide thee confounds singleness parts thou shouldst bear mark string sweet husband another strikes mutual ordering resembling sire child happy mother pleasing note sing whose speechless song many seeming sings thee thou single wilt prove none
    70 tokens: fear wet widows eye thou consumst thy self single life ah thou issueless shalt hap die world wail thee like makeless wife world thy widow still weep thou form thee hast left behind every private widow well keep childrens eyes husbands shape mind look unthrift world doth spend shifts place still world enjoys beautys waste hath world end kept unused user destroys love toward others bosom sits murdrous shame commits
    69 tokens: shame deny thou bearst love thy self art unprovident grant thou wilt thou art belovd many thou none lovst evident thou art possessd murderous hate gainst thy self thou stickst conspire seeking beauteous roof ruinate repair thy chief desire o change thy thought change mind shall hate fairer lodgd gentle love thy presence gracious kind thyself least kindhearted prove make thee another self love beauty still live thine thee

Create a word encoding. Sort the indices by frequency and encode only the top 100 words.

enc = wordEncoding(documents, ...
    'Order','frequency', ...
    'MaxNumWords',100)
enc = 
  wordEncoding with properties:

      NumWords: 100
    Vocabulary: [1x100 string]

View the words corresponding to indices 1, 2, and 3 using the ind2word function.

idx = [1 2 3];
words = ind2word(enc,idx)
words = 1x3 string array
    "thy"    "thou"    "love"

Load the example data. The file sonnetsPreprocessed.txt contains preprocessed versions of Shakespeare's sonnets. The file contains one sonnet per line, with words separated by a space. Extract the text from sonnetsPreprocessed.txt, split the text into documents at newline characters, and then tokenize the documents.

filename = "sonnetsPreprocessed.txt";
str = extractFileText(filename);
textData = split(str,newline);
documents = tokenizedDocument(textData);
documents(1:10)
ans = 
  10x1 tokenizedDocument:

    70 tokens: fairest creatures desire increase thereby beautys rose might never die riper time decease tender heir might bear memory thou contracted thine own bright eyes feedst thy lights flame selfsubstantial fuel making famine abundance lies thy self thy foe thy sweet self cruel thou art worlds fresh ornament herald gaudy spring thine own bud buriest thy content tender churl makst waste niggarding pity world else glutton eat worlds due grave thee
    71 tokens: forty winters shall besiege thy brow dig deep trenches thy beautys field thy youths proud livery gazed tatterd weed small worth held asked thy beauty lies treasure thy lusty days say thine own deep sunken eyes alleating shame thriftless praise praise deservd thy beautys thou couldst answer fair child mine shall sum count make old excuse proving beauty succession thine new made thou art old thy blood warm thou feelst cold
    65 tokens: look thy glass tell face thou viewest time face form another whose fresh repair thou renewest thou dost beguile world unbless mother fair whose uneard womb disdains tillage thy husbandry fond tomb selflove stop posterity thou art thy mothers glass thee calls back lovely april prime thou windows thine age shalt despite wrinkles thy golden time thou live rememberd die single thine image dies thee
    71 tokens: unthrifty loveliness why dost thou spend upon thy self thy beautys legacy natures bequest gives nothing doth lend frank lends free beauteous niggard why dost thou abuse bounteous largess thee give profitless usurer why dost thou great sum sums yet canst live traffic thy self alone thou thy self thy sweet self dost deceive nature calls thee gone acceptable audit canst thou leave thy unused beauty tombed thee lives th executor
    61 tokens: hours gentle work frame lovely gaze every eye doth dwell play tyrants same unfair fairly doth excel neverresting time leads summer hideous winter confounds sap checked frost lusty leaves quite gone beauty oersnowed bareness every summers distillation left liquid prisoner pent walls glass beautys effect beauty bereft nor nor remembrance flowers distilld though winter meet leese show substance still lives sweet
    68 tokens: let winters ragged hand deface thee thy summer ere thou distilld make sweet vial treasure thou place beautys treasure ere selfkilld forbidden usury happies pay willing loan thats thy self breed another thee ten times happier ten ten times thy self happier thou art ten thine ten times refigurd thee death thou shouldst depart leaving thee living posterity selfwilld thou art fair deaths conquest make worms thine heir
    64 tokens: lo orient gracious light lifts up burning head eye doth homage newappearing sight serving looks sacred majesty climbd steepup heavenly hill resembling strong youth middle age yet mortal looks adore beauty still attending golden pilgrimage highmost pitch weary car like feeble age reeleth day eyes fore duteous converted low tract look another way thou thyself outgoing thy noon unlookd diest unless thou get son
    70 tokens: music hear why hearst thou music sadly sweets sweets war joy delights joy why lovst thou thou receivst gladly else receivst pleasure thine annoy true concord welltuned sounds unions married offend thine ear sweetly chide thee confounds singleness parts thou shouldst bear mark string sweet husband another strikes mutual ordering resembling sire child happy mother pleasing note sing whose speechless song many seeming sings thee thou single wilt prove none
    70 tokens: fear wet widows eye thou consumst thy self single life ah thou issueless shalt hap die world wail thee like makeless wife world thy widow still weep thou form thee hast left behind every private widow well keep childrens eyes husbands shape mind look unthrift world doth spend shifts place still world enjoys beautys waste hath world end kept unused user destroys love toward others bosom sits murdrous shame commits
    69 tokens: shame deny thou bearst love thy self art unprovident grant thou wilt thou art belovd many thou none lovst evident thou art possessd murderous hate gainst thy self thou stickst conspire seeking beauteous roof ruinate repair thy chief desire o change thy thought change mind shall hate fairer lodgd gentle love thy presence gracious kind thyself least kindhearted prove make thee another self love beauty still live thine thee

Create a word encoding.

enc = wordEncoding(documents)
enc = 
  wordEncoding with properties:

      NumWords: 3092
    Vocabulary: [1x3092 string]

View the words corresponding to indices 1, 3, and 5 using the ind2word function.

idx = [1 3 5];
words = ind2word(enc,idx)
words = 1x3 string array
    "fairest"    "desire"    "thereby"

Load the example data. The file sonnetsPreprocessed.txt contains preprocessed versions of Shakespeare's sonnets. The file contains one sonnet per line, with words separated by a space. Extract the text from sonnetsPreprocessed.txt, split the text into documents at newline characters, and then tokenize the documents.

filename = "sonnetsPreprocessed.txt";
str = extractFileText(filename);
textData = split(str,newline);
documents = tokenizedDocument(textData);
documents(1:10)
ans = 
  10x1 tokenizedDocument:

    70 tokens: fairest creatures desire increase thereby beautys rose might never die riper time decease tender heir might bear memory thou contracted thine own bright eyes feedst thy lights flame selfsubstantial fuel making famine abundance lies thy self thy foe thy sweet self cruel thou art worlds fresh ornament herald gaudy spring thine own bud buriest thy content tender churl makst waste niggarding pity world else glutton eat worlds due grave thee
    71 tokens: forty winters shall besiege thy brow dig deep trenches thy beautys field thy youths proud livery gazed tatterd weed small worth held asked thy beauty lies treasure thy lusty days say thine own deep sunken eyes alleating shame thriftless praise praise deservd thy beautys thou couldst answer fair child mine shall sum count make old excuse proving beauty succession thine new made thou art old thy blood warm thou feelst cold
    65 tokens: look thy glass tell face thou viewest time face form another whose fresh repair thou renewest thou dost beguile world unbless mother fair whose uneard womb disdains tillage thy husbandry fond tomb selflove stop posterity thou art thy mothers glass thee calls back lovely april prime thou windows thine age shalt despite wrinkles thy golden time thou live rememberd die single thine image dies thee
    71 tokens: unthrifty loveliness why dost thou spend upon thy self thy beautys legacy natures bequest gives nothing doth lend frank lends free beauteous niggard why dost thou abuse bounteous largess thee give profitless usurer why dost thou great sum sums yet canst live traffic thy self alone thou thy self thy sweet self dost deceive nature calls thee gone acceptable audit canst thou leave thy unused beauty tombed thee lives th executor
    61 tokens: hours gentle work frame lovely gaze every eye doth dwell play tyrants same unfair fairly doth excel neverresting time leads summer hideous winter confounds sap checked frost lusty leaves quite gone beauty oersnowed bareness every summers distillation left liquid prisoner pent walls glass beautys effect beauty bereft nor nor remembrance flowers distilld though winter meet leese show substance still lives sweet
    68 tokens: let winters ragged hand deface thee thy summer ere thou distilld make sweet vial treasure thou place beautys treasure ere selfkilld forbidden usury happies pay willing loan thats thy self breed another thee ten times happier ten ten times thy self happier thou art ten thine ten times refigurd thee death thou shouldst depart leaving thee living posterity selfwilld thou art fair deaths conquest make worms thine heir
    64 tokens: lo orient gracious light lifts up burning head eye doth homage newappearing sight serving looks sacred majesty climbd steepup heavenly hill resembling strong youth middle age yet mortal looks adore beauty still attending golden pilgrimage highmost pitch weary car like feeble age reeleth day eyes fore duteous converted low tract look another way thou thyself outgoing thy noon unlookd diest unless thou get son
    70 tokens: music hear why hearst thou music sadly sweets sweets war joy delights joy why lovst thou thou receivst gladly else receivst pleasure thine annoy true concord welltuned sounds unions married offend thine ear sweetly chide thee confounds singleness parts thou shouldst bear mark string sweet husband another strikes mutual ordering resembling sire child happy mother pleasing note sing whose speechless song many seeming sings thee thou single wilt prove none
    70 tokens: fear wet widows eye thou consumst thy self single life ah thou issueless shalt hap die world wail thee like makeless wife world thy widow still weep thou form thee hast left behind every private widow well keep childrens eyes husbands shape mind look unthrift world doth spend shifts place still world enjoys beautys waste hath world end kept unused user destroys love toward others bosom sits murdrous shame commits
    69 tokens: shame deny thou bearst love thy self art unprovident grant thou wilt thou art belovd many thou none lovst evident thou art possessd murderous hate gainst thy self thou stickst conspire seeking beauteous roof ruinate repair thy chief desire o change thy thought change mind shall hate fairer lodgd gentle love thy presence gracious kind thyself least kindhearted prove make thee another self love beauty still live thine thee

Create a word encoding.

enc = wordEncoding(documents)
enc = 
  wordEncoding with properties:

      NumWords: 3092
    Vocabulary: [1x3092 string]

Map the words "rose", "love", and "beauty" to encoding indices using the word2ind function.

words = ["rose" "love" "beauty"];
idx = word2ind(enc,words)
idx = 1×3

     7   387    79

Load the weather reports data and create a tokenizedDocument array.

filename = "weatherReports.csv";
data = readtable(filename,'TextType','string');
textData = data.event_narrative;
documents = tokenizedDocument(textData);

Create a word encoding.

enc = wordEncoding(documents);

Convert the documents to sequences of word indices.

sequences = doc2sequence(enc,documents);

View the sizes of the first 10 sequences. Each sequence is a 1-by-S vector, where S is the number of word indices in the sequence. Because the sequences are padded, S is constant.

sequences(1:10)
ans = 10x1 cell array
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}
    {1x930 double}

Introduced in R2018b