Ontolearn is an open-source software library for learning owl class expressions at large scale.
Given positive and negative OWL named individual examples
To tackle this supervised learning problem, ontolearn offers many symbolic, neuro-symbolic and deep learning based Learning algorithms:
- Drill → Neuro-Symbolic Class Expression Learning
- EvoLearner → EvoLearner: Learning Description Logics with Evolutionary Algorithms
- NCES2 → (soon) Neural Class Expression Synthesis in ALCHIQ(D)
- NCES → Neural Class Expression Synthesis
- NERO → (soon) Learning Permutation-Invariant Embeddings for Description Logic Concepts
- CLIP → Learning Concept Lengths Accelerates Concept Learning in ALC
- CELOE → Class Expression Learning for Ontology Engineering
- OCEL → A limited version of CELOE
Find more in the Documentation.
pip install ontolearn
or
git clone https://github.com/dice-group/Ontolearn.git
# To create a virtual python env with conda
conda create -n venv python=3.10.14 --no-default-packages && conda activate venv && pip install -e .
# To download knowledge graphs
wget https://files.dice-research.org/projects/Ontolearn/KGs.zip -O ./KGs.zip && unzip KGs.zip
# To download learning problems
wget https://files.dice-research.org/projects/Ontolearn/LPs.zip -O ./LPs.zip && unzip LPs.zip
from ontolearn.learners import TDL
from ontolearn.triple_store import TripleStore
from ontolearn.knowledge_base import KnowledgeBase
from ontolearn.learning_problem import PosNegLPStandard
from owlapy.owl_individual import OWLNamedIndividual
from owlapy import owl_expression_to_sparql, owl_expression_to_dl
# (1) Initialize Triplestore or KnowledgeBase
# sudo docker run -p 3030:3030 -e ADMIN_PASSWORD=pw123 stain/jena-fuseki
# Login http://localhost:3030/#/ with admin and pw123 and upload KGs/Family/family.owl
# kb = TripleStore(url="http://localhost:3030/family")
kb = KnowledgeBase(path="KGs/Family/father.owl")
# (2) Initialize a learner.
model = TDL(knowledge_base=kb, use_nominals=True)
# (3) Define a description logic concept learning problem.
lp = PosNegLPStandard(pos={OWLNamedIndividual("http://example.com/father#stefan")},
neg={OWLNamedIndividual("http://example.com/father#heinz"),
OWLNamedIndividual("http://example.com/father#anna"),
OWLNamedIndividual("http://example.com/father#michelle")})
# (4) Learn description logic concepts best fitting (3).
h = model.fit(learning_problem=lp).best_hypotheses()
print(h)
print(owl_expression_to_dl(h))
print(owl_expression_to_sparql(expression=h))
"""
OWLObjectSomeValuesFrom(property=OWLObjectProperty(IRI('http://example.com/father#','hasChild')),filler=OWLObjectOneOf((OWLNamedIndividual(IRI('http://example.com/father#','markus')),)))
∃ hasChild.{markus}
SELECT
DISTINCT ?x WHERE {
?x <http://example.com/father#hasChild> ?s_1 .
FILTER ( ?s_1 IN (
<http://example.com/father#markus>
) )
}
"""
print(model.classification_report)
"""
Classification Report: Negatives: -1 and Positives 1
precision recall f1-score support
Negative 1.00 1.00 1.00 3
Positive 1.00 1.00 1.00 1
accuracy 1.00 4
macro avg 1.00 1.00 1.00 4
weighted avg 1.00 1.00 1.00 4
"""
from ontolearn.learners import TDL, Drill
from ontolearn.triple_store import TripleStore
from ontolearn.learning_problem import PosNegLPStandard
from owlapy.owl_individual import OWLNamedIndividual
from owlapy import owl_expression_to_sparql, owl_expression_to_dl
from ontolearn.utils.static_funcs import save_owl_class_expressions
# (1) Initialize Triplestore
kb = TripleStore(url="https://dbpedia.data.dice-research.org/sparql")
# (3) Initialize a learner.
model = Drill(knowledge_base=kb) # or TDL(knowledge_base=kb)
# (4) Define a description logic concept learning problem.
lp = PosNegLPStandard(pos={OWLNamedIndividual("http://dbpedia.org/resource/Angela_Merkel")},
neg={OWLNamedIndividual("http://dbpedia.org/resource/Barack_Obama")})
# (5) Learn description logic concepts best fitting (4).
h = model.fit(learning_problem=lp).best_hypotheses()
print(h)
print(owl_expression_to_dl(h))
print(owl_expression_to_sparql(expression=h))
save_owl_class_expressions(expressions=h,path="#owl_prediction")
Fore more please refer to the examples folder.
Click me!
Load an RDF knowledge graph
ontolearn-webservice --path_knowledge_base KGs/Mutagenesis/mutagenesis.owl
or launch a Tentris instance https://github.com/dice-group/tentris over Mutagenesis.
ontolearn-webservice --endpoint_triple_store http://0.0.0.0:9080/sparql
The below code trains DRILL with 6 randomly generated learning problems provided that path_to_pretrained_drill does not lead to a directory containing pretrained DRILL. Thereafter, trained DRILL is saved in the directory path_to_pretrained_drill. Finally, trained DRILL will learn an OWL class expression.
import json
import requests
with open(f"LPs/Mutagenesis/lps.json") as json_file:
learning_problems = json.load(json_file)["problems"]
for str_target_concept, examples in learning_problems.items():
response = requests.get('http://0.0.0.0:8000/cel',
headers={'accept': 'application/json', 'Content-Type': 'application/json'},
json={"pos": examples['positive_examples'],
"neg": examples['negative_examples'],
"model": "Drill",
"path_embeddings": "mutagenesis_embeddings/Keci_entity_embeddings.csv",
"path_to_pretrained_drill": "pretrained_drill",
# if pretrained_drill exists, upload, otherwise train one and save it there
"num_of_training_learning_problems": 2,
"num_of_target_concepts": 3,
"max_runtime": 60000, # seconds
"iter_bound": 1 # number of iterations/applied refinement opt.
})
print(response.json()) # {'Prediction': '∀ hasAtom.(¬Nitrogen-34)', 'F1': 0.7283582089552239, 'saved_prediction': 'Predictions.owl'}
TDL (a more scalable learner) can also be used as follows
import json
import requests
response = requests.get('http://0.0.0.0:8000/cel',
headers={'accept': 'application/json', 'Content-Type': 'application/json'},
json={"pos": examples['positive_examples'],
"neg": examples['negative_examples'],
"model": "TDL"})
print(response.json())
NCES (another scalable learner). The following will first train NCES if the provided path path_to_pretrained_nces
does not exist
import json
import requests
with open(f"LPs/Mutagenesis/lps.json") as json_file:
learning_problems = json.load(json_file)["problems"]
## This trains NCES before solving the provided learning problems. Expect poor performance for this number of epochs, and this training data size.
## If GPU is available, set `num_of_training_learning_problems` t0 10_000 or more. Set `nces_train_epochs` to 300 or more, and increase `nces_batch_size`.
for str_target_concept, examples in learning_problems.items():
response = requests.get('http://0.0.0.0:8000/cel',
headers={'accept': 'application/json', 'Content-Type': 'application/json'},
json={"pos": examples['positive_examples'],
"neg": examples['negative_examples'],
"model": "NCES",
"path_embeddings": "mutagenesis_embeddings/Keci_entity_embeddings.csv",
"path_to_pretrained_nces": None,
# if pretrained_nces exists, load weghts, otherwise train one and save it
"num_of_training_learning_problems": 100,
"nces_train_epochs": 5,
"nces_batch_size": 16
})
print(response.json())
Now this will use pretrained weights for NCES
import json
import requests
with open(f"LPs/Mutagenesis/lps.json") as json_file:
learning_problems = json.load(json_file)["problems"]
for str_target_concept, examples in learning_problems.items():
response = requests.get('http://0.0.0.0:8000/cel',
headers={'accept': 'application/json', 'Content-Type': 'application/json'},
json={"pos": examples['positive_examples'],
"neg": examples['negative_examples'],
"model": "NCES",
"path_embeddings": "./NCESData/mutagenesis/embeddings/ConEx_entity_embeddings.csv",
"path_to_pretrained_nces": "./NCESData/mutagenesis/trained_models/",
# if pretrained_nces exists, load weghts, otherwise train one and save it
"num_of_training_learning_problems": 100,
"nces_train_epochs": 5,
"nces_batch_size": 16
})
print(response.json())
To see the results
# To download learning problems. # Benchmark learners on the Family benchmark dataset with benchmark learning problems.
wget https://files.dice-research.org/projects/Ontolearn/LPs.zip -O ./LPs.zip && unzip LPs.zip
Here we apply 10-fold cross validation technique on each benchmark learning problem with max runtime of 60 seconds to measure the training and testing performance of learners. In the evaluation, from a given single learning problem (a set of positive and negative examples), a learner learns an OWL Class Expression (H) on a given 9 fold of positive and negative examples. To compute the training performance, We compute F1-score of H train positive and negative examples. To compute the test performance, we compute F1-score of H w.r.t. test positive and negative examples.
# To download learning problems and benchmark learners on the Family benchmark dataset with benchmark learning problems.
python examples/concept_learning_cv_evaluation.py --kb ./KGs/Family/family-benchmark_rich_background.owl --lps ./LPs/Family/lps_difficult.json --path_of_nces_embeddings ./NCESData/family/embeddings/ConEx_entity_embeddings.csv --path_of_clip_embeddings ./CLIPData/family/embeddings/ConEx_entity_embeddings.csv --max_runtime 60 --report family_results.csv
In the following python script, the results are summarized and the markdown displayed below generated.
import pandas as pd
df=pd.read_csv("family_results.csv").groupby("LP").mean()
print(df[[col for col in df if col.startswith('Test-F1') or col.startswith('RT')]].to_markdown(floatfmt=".3f"))
Note that DRILL is untrained and we simply used accuracy driven heuristics to learn an OWL class expression.
Below, we report the average test F1 score and the average runtimes of learners.
LP | Test-F1-OCEL | RT-OCEL | Test-F1-CELOE | RT-CELOE | Test-F1-Evo | RT-Evo | Test-F1-DRILL | RT-DRILL | Test-F1-TDL | RT-TDL | Test-F1-NCES | RT-NCES | Test-F1-CLIP | RT-CLIP |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Aunt | 0.614 | 13.697 | 0.855 | 13.697 | 0.978 | 5.278 | 0.811 | 60.351 | 0.956 | 0.118 | 0.812 | 1.168 | 0.855 | 14.059 |
Cousin | 0.712 | 10.846 | 0.789 | 10.846 | 0.993 | 3.311 | 0.701 | 60.485 | 0.820 | 0.176 | 0.677 | 1.050 | 0.779 | 9.050 |
Grandgranddaughter | 1.000 | 0.013 | 1.000 | 0.013 | 1.000 | 0.426 | 0.980 | 17.486 | 1.000 | 0.050 | 1.000 | 0.843 | 1.000 | 0.639 |
Grandgrandfather | 1.000 | 0.897 | 1.000 | 0.897 | 1.000 | 0.404 | 0.947 | 55.728 | 0.947 | 0.059 | 0.927 | 0.902 | 1.000 | 0.746 |
Grandgrandmother | 1.000 | 4.173 | 1.000 | 4.173 | 1.000 | 0.442 | 0.893 | 50.329 | 0.947 | 0.060 | 0.927 | 0.908 | 1.000 | 0.817 |
Grandgrandson | 1.000 | 1.632 | 1.000 | 1.632 | 1.000 | 0.452 | 0.931 | 60.358 | 0.911 | 0.070 | 0.911 | 1.050 | 1.000 | 0.939 |
Uncle | 0.876 | 16.244 | 0.891 | 16.244 | 0.964 | 4.516 | 0.876 | 60.416 | 0.933 | 0.098 | 0.891 | 1.256 | 0.928 | 17.682 |
LP | Train-F1-OCEL | Train-F1-CELOE | Train-F1-Evo | Train-F1-DRILL | Train-F1-TDL | Train-F1-NCES | Train-F1-CLIP |
---|---|---|---|---|---|---|---|
Aunt | 0.835 | 0.918 | 0.995 | 0.837 | 1.000 | 0.804 | 0.918 |
Cousin | 0.746 | 0.796 | 1.000 | 0.732 | 1.000 | 0.681 | 0.798 |
Grandgranddaughter | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 |
Grandgrandfather | 1.000 | 1.000 | 1.000 | 0.968 | 1.000 | 0.973 | 1.000 |
Grandgrandmother | 1.000 | 1.000 | 1.000 | 0.975 | 1.000 | 0.939 | 1.000 |
Grandgrandson | 1.000 | 1.000 | 1.000 | 0.962 | 1.000 | 0.927 | 1.000 |
Uncle | 0.904 | 0.907 | 0.996 | 0.908 | 1.000 | 0.884 | 0.940 |
python examples/concept_learning_cv_evaluation.py --kb ./KGs/Mutagenesis/mutagenesis.owl --lps ./LPs/Mutagenesis/lps.json --path_of_nces_embeddings ./NCESData/mutagenesis/embeddings/ConEx_entity_embeddings.csv --path_of_clip_embeddings ./CLIPData/mutagenesis/embeddings/ConEx_entity_embeddings.csv --max_runtime 60 --report mutagenesis_results.csv
LP | Train-F1-OCEL | Test-F1-OCEL | RT-OCEL | Train-F1-CELOE | Test-F1-CELOE | RT-CELOE | Train-F1-Evo | Test-F1-Evo | RT-Evo | Train-F1-DRILL | Test-F1-DRILL | RT-DRILL | Train-F1-TDL | Test-F1-TDL | RT-TDL | Train-F1-NCES | Test-F1-NCES | RT-NCES | Train-F1-CLIP | Test-F1-CLIP | RT-CLIP |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
NotKnown | 0.916 | 0.918 | 60.705 | 0.916 | 0.918 | 60.705 | 0.975 | 0.970 | 51.870 | 0.809 | 0.804 | 60.140 | 1.000 | 0.852 | 13.569 | 0.717 | 0.718 | 3.784 | 0.916 | 0.918 | 26.312 |
python examples/concept_learning_cv_evaluation.py --kb ./KGs/Carcinogenesis/carcinogenesis.owl --lps ./LPs/Carcinogenesis/lps.json --path_of_nces_embeddings ./NCESData/carcinogenesis/embeddings/ConEx_entity_embeddings.csv --path_of_clip_embeddings ./CLIPData/carcinogenesis/embeddings/ConEx_entity_embeddings.csv --max_runtime 60 --report carcinogenesis_results.csv
LP | Train-F1-OCEL | Test-F1-OCEL | RT-OCEL | Train-F1-CELOE | Test-F1-CELOE | RT-CELOE | Train-F1-Evo | Test-F1-Evo | RT-Evo | Train-F1-DRILL | Test-F1-DRILL | RT-DRILL | Train-F1-TDL | Test-F1-TDL | RT-TDL | Train-F1-NCES | Test-F1-NCES | RT-NCES | Train-F1-CLIP | Test-F1-CLIP | RT-CLIP |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
NOTKNOWN | 0.737 | 0.711 | 62.048 | 0.740 | 0.701 | 62.048 | 0.822 | 0.628 | 64.508 | 0.740 | 0.707 | 60.120 | 1.000 | 0.616 | 5.196 | 0.705 | 0.704 | 4.157 | 0.740 | 0.701 | 48.475 |
python examples/owl_class_expression_learning_dbpedia.py --model Drill && python examples/owl_class_expression_learning_dbpedia.py --model TDL
LP-Type | Train-F1-Drill | RT-Drill | Train-F1-TDL | RT-TDL |
---|---|---|---|---|
OWLObjectAllValuesFrom | 0.438 | 240.331 | 1.000 | 206.288 |
OWLObjectIntersectionOf | 0.213 | 202.558 | 0.717 | 91.660 |
OWLObjectUnionOf | 0.546 | 187.144 | 0.967 | 129.700 |
To see the results
Creating a feature branch refactoring from development branch
git branch refactoring develop
Each feature branch must be merged to develop branch. To this end, the tests must run without a problem:
# To download knowledge graphs
wget https://files.dice-research.org/projects/Ontolearn/KGs.zip -O ./KGs.zip && unzip KGs.zip
# To download learning problems
wget https://files.dice-research.org/projects/Ontolearn/LPs.zip -O ./LPs.zip && unzip LPs.zip
# Download weights for some model for few tests
wget https://files.dice-research.org/projects/NCES/NCES_Ontolearn_Data/NCESData.zip -O ./NCESData.zip && unzip NCESData.zip && rm NCESData.zip
wget https://files.dice-research.org/projects/Ontolearn/CLIP/CLIPData.zip && unzip CLIPData.zip && rm CLIPData.zip
pytest -p no:warnings -x # Running 76 tests takes ~ 17 mins
Currently, we are working on our manuscript describing our framework. If you find our work useful in your research, please consider citing the respective paper:
# DRILL
@inproceedings{demir2023drill,
author = {Demir, Caglar and Ngomo, Axel-Cyrille Ngonga},
booktitle = {The 32nd International Joint Conference on Artificial Intelligence, IJCAI 2023},
title = {Neuro-Symbolic Class Expression Learning},
url = {https://www.ijcai.org/proceedings/2023/0403.pdf},
year={2023}
}
# NCES2
@inproceedings{kouagou2023nces2,
author={Kouagou, N'Dah Jean and Heindorf, Stefan and Demir, Caglar and Ngonga Ngomo, Axel-Cyrille},
title={Neural Class Expression Synthesis in ALCHIQ(D)},
url = {https://papers.dice-research.org/2023/ECML_NCES2/NCES2_public.pdf},
booktitle={Machine Learning and Knowledge Discovery in Databases},
year={2023},
publisher={Springer Nature Switzerland},
address="Cham"
}
# NCES
@inproceedings{kouagou2023neural,
title={Neural class expression synthesis},
author={Kouagou, N’Dah Jean and Heindorf, Stefan and Demir, Caglar and Ngonga Ngomo, Axel-Cyrille},
booktitle={European Semantic Web Conference},
pages={209--226},
year={2023},
publisher={Springer Nature Switzerland}
}
# EvoLearner
@inproceedings{heindorf2022evolearner,
title={Evolearner: Learning description logics with evolutionary algorithms},
author={Heindorf, Stefan and Bl{\"u}baum, Lukas and D{\"u}sterhus, Nick and Werner, Till and Golani, Varun Nandkumar and Demir, Caglar and Ngonga Ngomo, Axel-Cyrille},
booktitle={Proceedings of the ACM Web Conference 2022},
pages={818--828},
year={2022}
}
# CLIP
@inproceedings{kouagou2022learning,
title={Learning Concept Lengths Accelerates Concept Learning in ALC},
author={Kouagou, N’Dah Jean and Heindorf, Stefan and Demir, Caglar and Ngonga Ngomo, Axel-Cyrille},
booktitle={European Semantic Web Conference},
pages={236--252},
year={2022},
publisher={Springer Nature Switzerland}
}
In case you have any question, please contact: caglar.demir@upb.de
or caglardemir8@gmail.com