Analyze syntax of a string

Break up the given text into a series of sentences and tokens (generally, words) and provide linguistic information about those tokens.

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For detailed documentation that includes this code sample, see the following:

Code sample

Go

To learn how to install and use the client library for Natural Language, see Natural Language client libraries. For more information, see the Natural Language Go API reference documentation.

To authenticate to Natural Language, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.


func analyzeSyntax(ctx context.Context, client *language.Client, text string) (*languagepb.AnnotateTextResponse, error) {
	return client.AnnotateText(ctx, &languagepb.AnnotateTextRequest{
		Document: &languagepb.Document{
			Source: &languagepb.Document_Content{
				Content: text,
			},
			Type: languagepb.Document_PLAIN_TEXT,
		},
		Features: &languagepb.AnnotateTextRequest_Features{
			ExtractSyntax: true,
		},
		EncodingType: languagepb.EncodingType_UTF8,
	})
}

Java

To learn how to install and use the client library for Natural Language, see Natural Language client libraries. For more information, see the Natural Language Java API reference documentation.

To authenticate to Natural Language, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

// Instantiate the Language client com.google.cloud.language.v1.LanguageServiceClient
try (com.google.cloud.language.v1.LanguageServiceClient language =
    com.google.cloud.language.v1.LanguageServiceClient.create()) {
  com.google.cloud.language.v1.Document doc =
      com.google.cloud.language.v1.Document.newBuilder().setContent(text)
        .setType(com.google.cloud.language.v1.Document.Type.PLAIN_TEXT).build();
  AnalyzeSyntaxRequest request =
      AnalyzeSyntaxRequest.newBuilder()
          .setDocument(doc)
          .setEncodingType(com.google.cloud.language.v1.EncodingType.UTF16)
          .build();
  // Analyze the syntax in the given text
  AnalyzeSyntaxResponse response = language.analyzeSyntax(request);
  // Print the response
  for (Token token : response.getTokensList()) {
    System.out.printf("\tText: %s\n", token.getText().getContent());
    System.out.printf("\tBeginOffset: %d\n", token.getText().getBeginOffset());
    System.out.printf("Lemma: %s\n", token.getLemma());
    System.out.printf("PartOfSpeechTag: %s\n", token.getPartOfSpeech().getTag());
    System.out.printf("\tAspect: %s\n", token.getPartOfSpeech().getAspect());
    System.out.printf("\tCase: %s\n", token.getPartOfSpeech().getCase());
    System.out.printf("\tForm: %s\n", token.getPartOfSpeech().getForm());
    System.out.printf("\tGender: %s\n", token.getPartOfSpeech().getGender());
    System.out.printf("\tMood: %s\n", token.getPartOfSpeech().getMood());
    System.out.printf("\tNumber: %s\n", token.getPartOfSpeech().getNumber());
    System.out.printf("\tPerson: %s\n", token.getPartOfSpeech().getPerson());
    System.out.printf("\tProper: %s\n", token.getPartOfSpeech().getProper());
    System.out.printf("\tReciprocity: %s\n", token.getPartOfSpeech().getReciprocity());
    System.out.printf("\tTense: %s\n", token.getPartOfSpeech().getTense());
    System.out.printf("\tVoice: %s\n", token.getPartOfSpeech().getVoice());
    System.out.println("DependencyEdge");
    System.out.printf("\tHeadTokenIndex: %d\n", token.getDependencyEdge().getHeadTokenIndex());
    System.out.printf("\tLabel: %s\n\n", token.getDependencyEdge().getLabel());
  }
  return response.getTokensList();
}

Node.js

To learn how to install and use the client library for Natural Language, see Natural Language client libraries. For more information, see the Natural Language Node.js API reference documentation.

To authenticate to Natural Language, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

// Imports the Google Cloud client library
const language = require('@google-cloud/language');

// Creates a client
const client = new language.LanguageServiceClient();

/**
 * TODO(developer): Uncomment the following line to run this code.
 */
// const text = 'Your text to analyze, e.g. Hello, world!';

// Prepares a document, representing the provided text
const document = {
  content: text,
  type: 'PLAIN_TEXT',
};

// Need to specify an encodingType to receive word offsets
const encodingType = 'UTF8';

// Detects the sentiment of the document
const [syntax] = await client.analyzeSyntax({document, encodingType});

console.log('Tokens:');
syntax.tokens.forEach(part => {
  console.log(`${part.partOfSpeech.tag}: ${part.text.content}`);
  console.log('Morphology:', part.partOfSpeech);
});

PHP

To learn how to install and use the client library for Natural Language, see Natural Language client libraries.

To authenticate to Natural Language, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

use Google\Cloud\Language\V1\AnalyzeSyntaxRequest;
use Google\Cloud\Language\V1\Client\LanguageServiceClient;
use Google\Cloud\Language\V1\Document;
use Google\Cloud\Language\V1\Document\Type;
use Google\Cloud\Language\V1\PartOfSpeech\Tag;

/**
 * @param string $text The text to analyze
 */
function analyze_syntax(string $text): void
{
    // Create the Natural Language client
    $languageServiceClient = new LanguageServiceClient();

    // Create a new Document, add text as content and set type to PLAIN_TEXT
    $document = (new Document())
        ->setContent($text)
        ->setType(Type::PLAIN_TEXT);

    // Call the analyzeEntities function
    $request = (new AnalyzeSyntaxRequest())
        ->setDocument($document);
    $response = $languageServiceClient->analyzeSyntax($request);
    $tokens = $response->getTokens();
    // Print out information about each entity
    foreach ($tokens as $token) {
        printf('Token text: %s' . PHP_EOL, $token->getText()->getContent());
        printf('Token part of speech: %s' . PHP_EOL, Tag::name($token->getPartOfSpeech()->getTag()));
        print(PHP_EOL);
    }
}

Python

To learn how to install and use the client library for Natural Language, see Natural Language client libraries. For more information, see the Natural Language Python API reference documentation.

To authenticate to Natural Language, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

from google.cloud import language_v1


def sample_analyze_syntax(text_content):
    """
    Analyzing Syntax in a String

    Args:
      text_content The text content to analyze
    """

    client = language_v1.LanguageServiceClient()

    # text_content = 'This is a short sentence.'

    # Available types: PLAIN_TEXT, HTML
    type_ = language_v1.Document.Type.PLAIN_TEXT

    # Optional. If not specified, the language is automatically detected.
    # For list of supported languages:
    # https://cloud.google.com/natural-language/docs/languages
    language = "en"
    document = {"content": text_content, "type_": type_, "language": language}

    # Available values: NONE, UTF8, UTF16, UTF32
    encoding_type = language_v1.EncodingType.UTF8

    response = client.analyze_syntax(
        request={"document": document, "encoding_type": encoding_type}
    )
    # Loop through tokens returned from the API
    for token in response.tokens:
        # Get the text content of this token. Usually a word or punctuation.
        text = token.text
        print(f"Token text: {text.content}")
        print(f"Location of this token in overall document: {text.begin_offset}")
        # Get the part of speech information for this token.
        # Part of speech is defined in:
        # http://www.lrec-conf.org/proceedings/lrec2012/pdf/274_Paper.pdf
        part_of_speech = token.part_of_speech
        # Get the tag, e.g. NOUN, ADJ for Adjective, et al.
        print(
            "Part of Speech tag: {}".format(
                language_v1.PartOfSpeech.Tag(part_of_speech.tag).name
            )
        )
        # Get the voice, e.g. ACTIVE or PASSIVE
        print(
            "Voice: {}".format(
                language_v1.PartOfSpeech.Voice(part_of_speech.voice).name
            )
        )
        # Get the tense, e.g. PAST, FUTURE, PRESENT, et al.
        print(
            "Tense: {}".format(
                language_v1.PartOfSpeech.Tense(part_of_speech.tense).name
            )
        )
        # See API reference for additional Part of Speech information available
        # Get the lemma of the token. Wikipedia lemma description
        # https://en.wikipedia.org/wiki/Lemma_(morphology)
        print(f"Lemma: {token.lemma}")
        # Get the dependency tree parse information for this token.
        # For more information on dependency labels:
        # http://www.aclweb.org/anthology/P13-2017
        dependency_edge = token.dependency_edge
        print(f"Head token index: {dependency_edge.head_token_index}")
        print(
            "Label: {}".format(
                language_v1.DependencyEdge.Label(dependency_edge.label).name
            )
        )

    # Get the language of the text, which will be the same as
    # the language specified in the request or, if not specified,
    # the automatically-detected language.
    print(f"Language of the text: {response.language}")

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