2025-06-21 12:29:04 -05:00

64 lines
2.3 KiB
Python

# Copyright (c) Sebastian Raschka under Apache License 2.0 (see LICENSE.txt).
# Source for "Build a Large Language Model From Scratch"
# - https://www.manning.com/books/build-a-large-language-model-from-scratch
# Code: https://github.com/rasbt/LLMs-from-scratch
from llms_from_scratch.ch04 import GPTModel, GPTModelFast
from llms_from_scratch.kv_cache.gpt2 import GPTModel as GPTModelKV
from llms_from_scratch.ch04 import generate_text_simple
from llms_from_scratch.kv_cache.generate import generate_text_simple as generate_text_simple_cached
import pytest
import torch
import tiktoken
GPT_CONFIG_124M = {
"vocab_size": 50257, # Vocabulary size
"context_length": 1024, # Context length
"emb_dim": 768, # Embedding dimension
"n_heads": 12, # Number of attention heads
"n_layers": 12, # Number of layers
"drop_rate": 0.1, # Dropout rate
"qkv_bias": False # Query-Key-Value bias
}
@pytest.mark.parametrize("ModelClass", [GPTModel, GPTModelFast, GPTModelKV])
@pytest.mark.parametrize("generate_fn", [generate_text_simple, generate_text_simple_cached])
def test_gpt_model_variants(ModelClass, generate_fn):
# Skip incompatible combinations
if generate_fn is generate_text_simple and getattr(ModelClass, "reset_kv_cache", False):
return
if generate_fn is generate_text_simple_cached and not getattr(ModelClass, "reset_kv_cache", False):
return
torch.manual_seed(123)
model = ModelClass(GPT_CONFIG_124M)
model.eval() # disable dropout
start_context = "Hello, I am"
tokenizer = tiktoken.get_encoding("gpt2")
encoded = tokenizer.encode(start_context)
encoded_tensor = torch.tensor(encoded).unsqueeze(0)
print(f"\n{50*'='}\n{22*' '}IN\n{50*'='}")
print("\nInput text:", start_context)
print("Encoded input text:", encoded)
print("encoded_tensor.shape:", encoded_tensor.shape)
out = generate_fn(
model=model,
idx=encoded_tensor,
max_new_tokens=10,
context_size=GPT_CONFIG_124M["context_length"]
)
expect = torch.tensor([
[15496, 11, 314, 716, 27018, 24086, 47843, 30961, 42348, 7267,
49706, 43231, 47062, 34657]
])
assert torch.equal(expect, out), "Generated output does not match expected output"