logicqubit 1.7.9

LogicQubit is a simple library for quantum computing simulation.

Features

• Numerical and symbolic simulation of quantum algorithms
• Plot state and current operation, density matrix and measurement graphs
• The state values can be represented as angles, which helps in the analysis of the fourrier quantum transform.
• Operations can be performed directly on the instantiated qubit object or using qubit indices.

Table of Contents

• Installation
• Startup
  • To instantiate a qubit
  • To instantiate a qubit register
• Operations
  • Operations on one qubit
  • Operations on two qubits
  • List of available gates
• Measure
  • Measure the expected value of one or more qubits
  • Measure one shot on a qubit
• Plot graphs and print state
  • Plot expected values
  • Plot the density matrix
  • Print the current state
  • Print the current state as angles
• Code sample
• Other code samples

Installation

CPU-only install:

pip install logicqubit

GPU (PyTorch/CUDA) extras:

pip install "logicqubit[cuda]"

Startup

logicQuBit = LogicQuBit(n_qubits, symbolic = True)

Additional optional keyword arguments let you choose the TensorNetwork backend and toggle CUDA acceleration:

logicQuBit = LogicQuBit(
    n_qubits,
    tn_backend="numpy",   # or "jax", "pytorch", "tensorflow"
    enable_cuda=False     # set to True to try a GPU-capable backend
)

Where n_qubits is the number of qubits, and symbolic defines whether the values a and b of the qubits will be symbolic or not, if the symbolic input is omitted the calculation will be numeric.

To instantiate a qubit

q = Qubit()

To instantiate a qubit register

reg = QubitRegister(num_qubits)

Operations

Operations on one qubit

The operation can be performed as q.Gate(parameters) or logicQuBit.Gate(id_qubit, parameters).

Operations on two qubits

In this case, the operation can be performed as q.Gate(control_qubit, parameters) or logicQuBit.Gate(control_qubit, target_qubit, parameters).

*The need for parameters depends on the type of gate.

List of available gates

Single-qubit gates: X, Y, Z, V, S, T, H, RX, RY, RZ, U, U1, U2, U3.

Two-qubits gates: CX or CNOT, CY, CZ, CV, CS, CT, CRX, CRY, CRZ, CU, CU1, CU2, CU3, SWAP.

Three-qubits gates: CCX or Toffoli, Fredkin.

Measure

Measure the expected value of one or more qubits

result = logicQuBit.Measure([q1,q2,..,qn])

Measure one shot on a qubit

value = logicQuBit.Measure_One(qubit)

Plot graphs and print state

Plot expected values

logicQuBit.plot()

Generate a graph of the values obtained by the Measure([...]).

Plot the density matrix

logicQuBit.PlotDensityMatrix()

Print the current state

logicQuBit.PrintState()

Print the current state as angles

logicQuBit.getPsiAtAngles(degree=True)

The degree variable defines whether the result will be displayed in degrees or radians.

Code sample

from logicqubit.logic import *

logicQuBit  = LogicQuBit(3)

a = Qubit()
b = Qubit()
c = Qubit()

a.H()
b.H()

c.CCX(a,b) # and operation

logicQuBit.Measure([c])
logicQuBit.Plot()

Other code samples

https://github.com/clnrp/logicqubit-algorithms