textBoundary — Create a pattern matching the start or end of text.
textBoundary creates a lightweight RunMat pattern object that matches the start or end of text.
Syntax
pat = textBoundary
pat = textBoundary(type)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
type | StringScalar | Yes | "either" | Boundary type: "either", "start", or "end". |
Returns
| Name | Type | Description |
|---|---|---|
out | Any | Output value. |
How textBoundary works
textBoundaryandtextBoundary("either")create a pattern that matches either the start or end of a text scalar.textBoundary("start")matches only the start of text.textBoundary("end")matches only the end of text.- The boundary
typeargument accepts string scalars or character vectors and is matched case-insensitively. - Returned pattern objects are regular-expression-backed and can be used by RunMat pattern-aware string APIs such as
contains,startsWith,endsWith,erase, andreplace. - Full MATLAB pattern-expression algebra, including
textBoundary + otherPatterncomposition and~textBoundarynegation, remains broader pattern infrastructure work.
GPU memory and residency
textBoundary creates a host pattern object; no provider-resident execution is applicable.
Examples
Create A Start Boundary Pattern
pat = textBoundary("start")Expected output:
`pat` is a pattern object backed by a start-of-text boundary.Create An End Boundary Pattern
pat = textBoundary("end")Expected output:
`pat` is a pattern object backed by an end-of-text boundary.Using textBoundary with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how textBoundary changes the result.
Run a small textBoundary example, explain the result, then change one input and compare the output.
FAQ
Does textBoundary support pattern negation?⌄
Not in this slice. The constructor returns a boundary pattern object, but full MATLAB pattern algebra such as ~textBoundary remains broader pattern infrastructure work.
Does textBoundary execute on the GPU?⌄
No. It creates host pattern metadata; pattern-aware text consumers gather GPU-resident text before matching.
Related Strings functions
Pattern
digitsPattern · lettersPattern · pattern · regexpPattern · wildcardPattern
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 · word2ind · 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
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how textBoundary is executed, line by line, in Rust.
- View the source for textBoundary 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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