Genetic Algorithm for VQC ansatz search

1.0.14 verified Sat May 09 auth: no python

GA-VQC provides a genetic algorithm to automatically search for optimal variational quantum circuit (VQC) ansätze for quantum machine learning tasks. Version 1.0.14 is the latest; development appears to be active on GitHub.

pip install ga-vqc

Common errors

error ModuleNotFoundError: No module named 'ga_vqc' ↓

cause Incorrect import path; correct module name is 'gavqc'.

fix

Use: from gavqc import GenAlg

error TypeError: __init__() got an unexpected keyword argument 'X' ↓

cause GenAlg expects 'X' and 'y' as positional or keyword arguments, but older versions used different parameter names.

fix

Ensure you are using the latest version (pip install --upgrade ga-vqc). The current API accepts 'X' and 'y'.

Warnings

breaking Import path changed: module name is 'gavqc' (not 'ga_vqc' or 'ga-vqc'). ↓

fix Use 'from gavqc import ...' instead of 'import ga_vqc'.

gotcha GenAlg.run() modifies the instance; best circuit stored in GenAlg.best_circuit attribute. ↓

fix Access results via the GenAlg instance after calling run().

deprecated Support for Qiskit <0.45 is dropped. ↓

fix Upgrade to Qiskit 0.45+.

Imports

GenAlg
wrong
```
from ga_vqc import GenAlg
```
correct
```
from gavqc import GenAlg
```
Module name uses lowercase 'gavqc', not hyphen or underscore.

VQCAnsatz

wrong

from ga_vqc.ansatz import VQCAnsatz

correct

from gavqc import VQCAnsatz

VQCAnsatz is exported from top-level gavqc.

Quickstart

Minimal example to run genetic algorithm for VQC ansatz search.

from gavqc import GenAlg
from qiskit.circuit import QuantumCircuit
from qiskit.circuit.library import RealAmplitudes
import numpy as np

# Example: optimize a simple circuit structure
ansatz = RealAmplitudes(2, reps=1)
X = np.random.rand(10, 2)
y = np.random.randint(0, 2, 10)

ga = GenAlg(
    ansatz=ansatz,
    X=X, y=y,
    generations=10,
    population_size=10,
    mutation_rate=0.1
)
ga.run()
print("Best fitness:", ga.best_fitness)
print("Best circuit:", ga.best_circuit)