---
license: mit
---

# CAT-LM: Aligned <u>C</u>ode <u>A</u>nd <u>T</u>ests Language Model

### Model Description
**CAT-LM** is a GPT-style language model with 2.7 Billion parameters, trained on a corpus of Python and Java projects (~260GB). It supports a maximum sequence length of 8,192 tokens. We utilize a novel pretraining signal that explicitly considers the mapping between code and test files when available.

### Publication

[CAT-LM: Training Language Models on Aligned Code And Tests](https://conf.researchr.org/details/ase-2023/ase-2023-papers/59/CAT-LM-Training-Language-Models-on-Aligned-Code-And-Tests)  
[Nikitha Rao](https://raonikitha.github.io)\*, [Kush Jain](https://www.kushjain.com/)\*, [Uri Alon](https://urialon.ml), [Claire Le Goues](https://clairelegoues.com), and [Vincent J. Hellendoorn](http://vhellendoorn.github.io)\
38th IEEE/ACM International Conference on Automated Software Engineering (ASE 2023)

### Usage

```python
from transformers import AutoModelForCausalLM, AutoTokenizer

tokenizer = AutoTokenizer.from_pretrained('nikitharao/catlm', use_fast = False)
model = AutoModelForCausalLM.from_pretrained('nikitharao/catlm')

prompt = """
def add(x,y):
    \"\"\"Add two numbers x and y\"\"\"
    return x+y
<|codetestpair|>
"""

print('Input prompt:')
print(prompt)
       
input_ids = tokenizer(prompt, return_tensors="pt").input_ids

# The model was trained without the `</s>` token and should be removed.
if tokenizer.decode(input_ids[0,-1]) == '</s>':
    input_ids = input_ids[:,:-1]

print(input_ids)
len_input = input_ids.shape[1]

sample_output = model.generate(
    input_ids,
    do_sample=True, 
    max_new_tokens = 512,
    top_k=50, 
    top_p=0.95,
    temperature=0.2
)
generated_output = sample_output[0][len_input:]
output = tokenizer.decode(generated_output, skip_special_tokens=True)
print('Output:')
print(output)
```

<b>Note:</b> The model was trained without the `</s>` token and should be removed.

Please see https://github.com/RaoNikitha/CAT-LM for more details.