LLamaSharp/LLama/LLamaWeights.cs

128 lines
4.1 KiB
C#

using System;
using System.Collections.Generic;
using System.Text;
using LLama.Abstractions;
using LLama.Extensions;
using LLama.Native;
using Microsoft.Extensions.Logging;
namespace LLama
{
/// <summary>
/// A set of model weights, loaded into memory.
/// </summary>
public sealed class LLamaWeights
: IDisposable
{
/// <summary>
/// The native handle, which is used in the native APIs
/// </summary>
/// <remarks>Be careful how you use this!</remarks>
public SafeLlamaModelHandle NativeHandle { get; }
/// <summary>
/// Total number of tokens in vocabulary of this model
/// </summary>
public int VocabCount => NativeHandle.VocabCount;
/// <summary>
/// Total number of tokens in the context
/// </summary>
public int ContextSize => NativeHandle.ContextSize;
/// <summary>
/// Get the size of this model in bytes
/// </summary>
public ulong SizeInBytes => NativeHandle.SizeInBytes;
/// <summary>
/// Get the number of parameters in this model
/// </summary>
public ulong ParameterCount => NativeHandle.ParameterCount;
/// <summary>
/// Get the newline token for this model
/// </summary>
public LLamaToken NewlineToken => NativeApi.llama_token_nl(NativeHandle);
/// <summary>
/// Get the "end of sentence" token for this model
/// </summary>
public LLamaToken EndOfSentenceToken => NativeApi.llama_token_eos(NativeHandle);
/// <summary>
/// Get the "beginning of sentence" token for this model
/// </summary>
public LLamaToken BeginningOfSentenceToken => NativeApi.llama_token_bos(NativeHandle);
/// <summary>
/// Dimension of embedding vectors
/// </summary>
public int EmbeddingSize => NativeHandle.EmbeddingSize;
/// <summary>
/// All metadata keys in this model
/// </summary>
public IReadOnlyDictionary<string, string> Metadata { get; set; }
private LLamaWeights(SafeLlamaModelHandle weights)
{
NativeHandle = weights;
Metadata = weights.ReadMetadata();
}
/// <summary>
/// Load weights into memory
/// </summary>
/// <param name="params"></param>
/// <returns></returns>
public static LLamaWeights LoadFromFile(IModelParams @params)
{
using var pin = @params.ToLlamaModelParams(out var lparams);
var weights = SafeLlamaModelHandle.LoadFromFile(@params.ModelPath, lparams);
foreach (var adapter in @params.LoraAdapters)
{
if (string.IsNullOrEmpty(adapter.Path))
continue;
if (adapter.Scale <= 0)
continue;
weights.ApplyLoraFromFile(adapter.Path, adapter.Scale, @params.LoraBase);
}
return new LLamaWeights(weights);
}
/// <inheritdoc />
public void Dispose()
{
NativeHandle.Dispose();
}
/// <summary>
/// Create a llama_context using this model
/// </summary>
/// <param name="params"></param>
/// <param name="logger"></param>
/// <returns></returns>
public LLamaContext CreateContext(IContextParams @params, ILogger? logger = null)
{
return new LLamaContext(this, @params, logger);
}
/// <summary>
/// Convert a string of text into tokens
/// </summary>
/// <param name="text"></param>
/// <param name="add_bos"></param>
/// <param name="encoding"></param>
/// <param name="special">Allow tokenizing special and/or control tokens which otherwise are not exposed and treated as plaintext.</param>
/// <returns></returns>
public LLamaToken[] Tokenize(string text, bool add_bos, bool special, Encoding encoding)
{
return NativeHandle.Tokenize(text, add_bos, special, encoding);
}
}
}