Text hashingvectorizer loadasync

HashingVectorizer.LoadAsync

Read the options back without blocking the caller.

public static Task<HashingVectorizer> LoadAsync(Stream source, ArtifactLoadOptions options = null, CancellationToken cancellationToken = default)

Parameters — source is a readable stream, left open. options bounds what will be accepted. cancellationToken cancels the read.

Returns — Task<HashingVectorizer>, completing with a vectorizer ready to transform.

Exceptions — ArgumentNullException for a null source. InvalidDataException for content that is not a saved vectorizer or that exceeds a bound. OperationCanceledException when cancelled.

Example — restored asynchronously, hashing as before.

using Lodestar.Text.Vectorization;

static async Task<bool> RestoreAsync()
{
    var original = new HashingVectorizer(new HashingVectorizerOptions { NumFeatures = 16 });

    using var buffer = new MemoryStream();
    await original.SaveAsync(buffer);
    buffer.Position = 0;

    HashingVectorizer restored = await HashingVectorizer.LoadAsync(buffer);
    return restored.NumFeatures == original.NumFeatures;
}

bool identical = RestoreAsync().GetAwaiter().GetResult();  // => True

The GetAwaiter().GetResult() is only what lets a synchronous example drive an async one; in async code the call is simply await.

Remarks — the bounds in options are checked as the content is read. They matter less here than for the vectorizers that carry a vocabulary, since the content is a few settings, and they are applied anyway so that one loading path behaves the same everywhere.

Applies to — net10.0, netstandard2.0.

See also — HashingVectorizer.Load, HashingVectorizer.SaveAsync, ArtifactLoadOptions.