clausy: clausify feature-model formulas 🎅

clausy transforms feature-model formulas into conjunctive normal form (CNF) for subsequent analysis.

Getting Started

To transform any .sat, .model, or FeatureIDE-compatible file into .cnf (aka .dimacs), run:

git clone --recursive https://github.com/ekuiter/clausy.git
cd clausy

# option 1: build as Docker image
docker build -t clausy .
cat meta/simple.sat | docker run --rm -i clausy

# option 2: build locally into build/ directory
make
make external # optional: compile external solvers
build/clausy -i meta/simple.sat

# option 3: download precompiled binaries for 64-bit Linux
wget https://nightly.link/ekuiter/clausy/workflows/static/main/build.zip
unzip build.zip

You can also click here to download precompiled binaries for 64-bit Linux.

Depending on the invocation, external tools may be needed (e.g., Java for parsing FeatureIDE-compatible files).

Advanced Usage, Documentation, and Tests

Documentation for clausy is available online.

# equivalent to the above, but more explicit
build/clausy -i meta/simple.sat -t cnf-dist print

# read from standard input and count solutions with Tseitin transformation
cat model.uvl | build/clausy -i -.uvl -t canon -t cnf-tseitin count

# read from command line and find some solution
echo '(!def(a)|def(b))' | build/clausy -i -.model -t cnf-dist satisfy

# prove a tautology
echo '(def(a)|!def(a))' | build/clausy -i -.model -i '(-1)' -t cnf-tseitin satisfy &>/dev/null; test $? -eq 20

# prove model equivalence
build/clausy -i a.model -i b.model -i '+(*(-1 2) *(1 -2))' -t cnf-tseitin satisfy &>/dev/null; test $? -eq 20

# compute diff statistics
build/clausy -i a.model -i b.model diff

# serialize diff
build/clausy -i a.model -i b.model diff --left slice --right slice --output-prefix a_to_b
 
# simplify a given CNF
build/clausy -i model.dimacs

# advanced usage via Docker (file I/O with standard input)
cat meta/simple.sat | docker run --rm -i clausy -i -.sat -t cnf-tseitin count

# advanced usage via Docker (file I/O with volumes)
docker run --rm -v ./a.xml:/a.xml -v ./b.xml:/b.xml -v ./diff:/diff clausy -i /a.xml -i /b.xml diff --left slice --right slice --output-prefix /diff/a_to_b

# run tests
make test

# view documentation
make doc

# view live documentation (for developers)
make doc-live

CNF Transformation Zoo

We also maintain a detailed table of tools that implement a CNF transformation. Key differences to clausy include:

• Most of the listed tools are not or only sparsely documented. clausy, in contrast, is extensively documented.
• Some of the listed tools have additional features that are not related to CNF transformation. clausy, in contrast, is focused and specialized, making it easier to understand/debug and ideal for learning and experimentation purposes.
• Most of the listed tools have relatively limited options for input formats. clausy, in contrast, has a diverse set of inputs, as it extends FeatureIDE's inputs with additional formats.

License

The source code of this project is released under the LGPL v3 license.