cypari

2.5.6 verified Fri May 01 auth: no python maintenance

A standalone Python interface to the PARI/GP computer algebra system, extracted from SageMath. Version 2.5.6 (2024?) provides basic number theory functions, elliptic curves, and polynomial arithmetic. Development appears slow; latest release is from 2020?.

pip install cypari

Common errors

error ModuleNotFoundError: No module named 'cypari' ↓

cause Trying to import 'cypari' but the actual module is 'cypari2'.

fix

Use import cypari2 instead of import cypari.

error ImportError: cannot import name 'Pari' from 'cypari' ↓

cause After successful import of 'cypari' (if eventually loaded), the symbol is not there.

fix

Use from cypari2 import Pari.

Warnings

gotcha The import module is `cypari2`, not `cypari`. Even though the PyPI package is `cypari`, all imports use the `cypari2` namespace. ↓

fix Use `import cypari2` instead of `import cypari`.

deprecated Older versions (pre-2.0) used `from cypari import Pari` directly. This no longer works. ↓

fix Update to `from cypari2 import Pari`.

Imports

cypari2
wrong
```
import cypari
```
correct
```
import cypari2
```
Package name is cypari, but top-level module is cypari2. Use cyipopt pattern?
Pari
wrong
```
from cypari import Pari
```
correct
```
from cypari2 import Pari
```
Direct import from cypari fails; must use cypari2.

Quickstart

Initialize a PARI session and compute factorization.

from cypari2 import Pari
pari = Pari()
print(pari('factor(123456789)'))