Metadata-Version: 2.4
Name: gansu2
Version: 2026.9.21
Summary: GPU Accelerated Numerical Simulation Utility for quantum chemistry
Author: Hiroshima University / Fujitsu Limited
License: BSD-3-Clause
Project-URL: Homepage, https://gansu2.github.io/
Project-URL: Documentation, https://gansu2.github.io/en/
Project-URL: Releases, https://github.com/gansu2/dist/releases
Project-URL: User Portal, https://gansu2.github.io/portal/
Keywords: quantum-chemistry,gpu,hartree-fock,ccsd,cuda
Classifier: Development Status :: 4 - Beta
Classifier: Intended Audience :: Science/Research
Classifier: License :: OSI Approved :: BSD License
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: 3.11
Classifier: Programming Language :: Python :: 3.12
Classifier: Programming Language :: Python :: 3.13
Classifier: Topic :: Scientific/Engineering :: Chemistry
Classifier: Operating System :: POSIX :: Linux
Requires-Python: >=3.8
Description-Content-Type: text/markdown
License-File: LICENSE
Requires-Dist: numpy
Requires-Dist: nvidia-cuda-runtime-cu12
Requires-Dist: nvidia-cublas-cu12
Requires-Dist: nvidia-cusolver-cu12
Requires-Dist: nvidia-cusparse-cu12
Requires-Dist: nvidia-nccl-cu12
Dynamic: license-file

# GANSU2

[![PyPI](https://img.shields.io/pypi/v/gansu2.svg)](https://pypi.org/project/gansu2/) [![PyPI Downloads](https://static.pepy.tech/personalized-badge/gansu2?period=total&units=INTERNATIONAL_SYSTEM&left_color=BLACK&right_color=GREEN&left_text=downloads)](https://pepy.tech/projects/gansu2)

**GANSU2** (GPU Accelerated Numerical Simulation Utility) is a GPU-native quantum
chemistry package: Hartree-Fock, Kohn-Sham DFT, post-HF (MP2, CCSD, CCSD(T),
DLPNO-CCSD, DMET, FCI), excited states (CIS, ADC(2), EOM-CCSD, STEOM-CCSD),
analytic gradients / Hessians and geometry optimization, all in double precision
on NVIDIA GPUs. It is distributed as a small `pip` wheel plus a licensed shared
library that is fetched on first use.

Full documentation: **https://gansu2.github.io/**

## Install

```bash
pip install gansu2
```

No CUDA toolkit, no compiler, no `cmake` on your side. The wheel is a thin
Python wrapper; the CUDA 12 runtime libraries come in as `pip` dependencies
(`nvidia-cublas-cu12`, `nvidia-cusolver-cu12`, ...). On first use GANSU2
downloads the GPU shared library `libgansu2.so` and the `gansu2` command-line
tool from the matching [release](https://github.com/gansu2/dist/releases),
verifies them against their published SHA-256, and caches them under
`~/.cache/gansu2/<version>/`.

**Requirements**

* Linux x86_64 (`manylinux_2_28`: Ubuntu 20.04+, Debian 10+, RHEL 8+ and equivalents)
* Python 3.8+
* NVIDIA driver compatible with the CUDA 12.x runtime (>= 525.60.13)
* NVIDIA GPU with Compute Capability 8.0+ (Ampere / Ada / Hopper / Blackwell)

## Quick test

```python
import gansu2

gansu2.init()
m = gansu2.Molecule("H2O.xyz", basis="sto-3g")
print(f"RHF energy: {m.run(method='RHF').total_energy:.6f} Ha")
gansu2.finalize()
```

Or from the command line (the `gansu2` command is installed by the wheel):

```bash
gansu2 -x H2O.xyz -g sto-3g                                   # RHF
gansu2 -x H2O.xyz -g cc-pvdz --post_hf_method ccsd            # CCSD
gansu2 -x H2O.xyz -g cc-pvdz --method rks --functional pbe    # DFT (RKS / PBE)
gansu2 -x H2O.xyz -g cc-pvdz -r optimize                      # geometry optimization
gansu2 --list-basis                                           # bundled basis sets
```

## License key

Small calculations run without any license. Larger ones need a **free license
key**, which grants full, unlimited use (commercial use included):

1. `gansu2-license -s` prints an 8-character sign-up code.
2. Create an account at the [User Portal](https://gansu2.github.io/portal/),
   enter the sign-up code, and press **Start**. Your key is emailed to you.
3. `gansu2-license -k <YOUR-KEY> -a` registers the key on the machine.

The key is a floating license: it is not tied to a machine. See the
[installation guide](https://gansu2.github.io/en/INSTALL.html) and the
[Terms and Conditions](https://gansu2.github.io/en/TERMS/).

## Offline / air-gapped use

Download the wheel and the matching `libgansu2.so` from the
[release page](https://github.com/gansu2/dist/releases) on a connected machine,
then on the target machine:

```bash
pip install ./gansu2-<version>-py3-none-manylinux_2_28_x86_64.whl
export GANSU2_LIB=/path/to/libgansu2-<version>-linux-x86_64.so
python -c "import gansu2; gansu2.init()"
```

`GANSU2_LIB` makes the loader use that file instead of downloading.

## Documentation

* [Installation](https://gansu2.github.io/en/INSTALL.html)
* [CLI guide](https://gansu2.github.io/en/usage_cli/)
* [Python API guide](https://gansu2.github.io/en/usage_python/)
* [C API reference](https://gansu2.github.io/en/usage_c_api/)
* [All parameters](https://gansu2.github.io/en/parameters/)

## Acknowledgements and license

GANSU2 is developed by Hiroshima University and Fujitsu Limited. It is derived
from the open-source GANSU project (BSD-3-Clause,
https://github.com/Yasuaki-Ito/GANSU); the BSD-3-Clause notice of GANSU is
retained in the distribution. Use of the GANSU2 binaries is governed by the
[Terms and Conditions](https://gansu2.github.io/en/TERMS/).
