word2ind — Map words to indices in a wordEncoding object.
word2ind(enc, words) returns vocabulary indices for words in a wordEncoding object.
Syntax
M = word2ind(enc, words)
M = word2ind(enc, words, 'IgnoreCase', true)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
enc | Any | Yes | — | wordEncoding object. |
words | Any | Yes | — | Words to map to indices. |
NameValue | Any | Variadic | — | Name-value options: IgnoreCase. |
Returns
| Name | Type | Description |
|---|---|---|
M | NumericArray | Word encoding indices, with NaN for words outside the vocabulary. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:word2ind:InvalidInput | Inputs do not match a supported word2ind form. | word2ind received invalid input |
How word2ind works
encmust be awordEncodingobject.wordsmay be a string scalar, string array, character vector, character matrix, or cell array of scalar text.- The output numeric tensor preserves the input word container shape for string arrays and cell arrays. A character vector returns a scalar 1-by-1 tensor; a character matrix returns one row per input row.
- Indices are 1-based. Words missing from the vocabulary return
NaN. word2ind(___, 'IgnoreCase', true)performs case-insensitive vocabulary lookup and uses the first matching vocabulary entry.- The input surface is textual: native integer arrays and resident numeric arrays are rejected rather than converted to words. The returned indices are double values, with
NaNrepresenting missing words.
GPU memory and residency
word2ind reads host text and model metadata and returns a CPU double tensor. Numeric resident inputs are rejected before provider access because they are not valid word inputs.
Example
Map Words To Indices
enc = wordEncoding(["rose" "love" "beauty"]);
idx = word2ind(enc, ["rose" "missing"])Expected output:
`idx` is `[1 NaN]`.Using word2ind with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how word2ind changes the result.
Run a small word2ind example, explain the result, then change one input and compare the output.
FAQ
What happens for missing words?⌄
RunMat returns NaN for words outside the encoding vocabulary.
Does word2ind execute on the GPU?⌄
No. It is a host text lookup.
Related Strings functions
Text Analytics
addDependencyDetails · addEntityDetails · addLemmaDetails · addPartOfSpeechDetails · addSentenceDetails · addTypeDetails · bagOfNgrams · bagOfWords · cosineSimilarity · doc2sequence · encode · extractFileText · extractHTMLText · fastTextWordEmbedding · findElement · getAttribute · htmlTree · ind2word · isVocabularyWord · normalizeWords · readWordEmbedding · removeLongWords · removeShortWords · removeStopWords · removeWords · stopWords · tokenDetails · tokenizedDocument · trainWordEmbedding · vaderSentimentScores · vec2word · word2vec · wordEncoding · writeWordEmbedding
Transform
append · deblank · erase · eraseBetween · erasePunctuation · eraseURLs · extractAfter · extractBefore · extractBetween · insertAfter · insertBefore · join · lower · pad · replace · replaceBetween · reverse · split · splitlines · strcat · strip · strjoin · strjust · strrep · strsplit · strtrim · upper
Core
blanks · char · compose · convertCharsToStrings · convertContainedStringsToChars · convertStringsToChars · genvarname · int2str · isletter · isspace · isStringScalar · isstrprop · mat2str · native2unicode · newline · num2str · sprintf · sscanf · str2double · str2num · strcmp · strcmpi · string · string.empty · strings · strlength · strncmp · strncmpi · strtok · unicode2native
Search
contains · endsWith · matches · startsWith · strfind
Pattern
digitsPattern · lettersPattern · pattern · regexpPattern · textBoundary · wildcardPattern
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how word2ind is executed, line by line, in Rust.
- View the source for word2ind in Rust on GitHub
- Learn how the RunMat runtime works
- Found a bug? Open an issue with a minimal reproduction.
About RunMat
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