Skip to main content

Visualization tools for the qubit Bloch sphere

Project description

Qubit Bloch Sphere Visualization

A collection of visualization tools for the qubit Bloch sphere. The Bloch sphere is a useful representation of the state of a single-qubit quantum computer.

X gate comparison with Hadamard-Z-Hadamard

See also: Feynman path integral visualization

Install

bloch_sphere is available on PyPI:

python3 -m pip install bloch_sphere

Prerequisites

Cairo needs to be installed separately to render videos. See platform-specific instructions for Linux, Windows, and macOS from Cairo. Below are some examples for installing Cairo on Linux distributions and macOS.

Ubuntu

sudo apt-get install libcairo2

macOS

Using homebrew:

brew install cairo

Usage

This package provides a command line tool to generate animations. In your shell, run the following (run animate_bloch -h for help).

animate_bloch hadamard x y s s
animate_bloch2 xy_vs_z x,y z

With annotations:

animate_bloch2 xy_vs_z_annotated \
    x,y z \
    --circuit '& \gate{X} & \gate{Y} & \qw & \push{=} & & \gate{Z} & \qw' \
    --equation '$YX\ket{\psi}=Z\ket{\psi}$' \
    --fps 20 \
    --mp4

Custom gates: custom;<x-axis>;<y-axis>;<z-axis>;<number half rotations>;<label>

animate_bloch2 custom_hzy "custom;0;1;1;1;Hzy" "s,h,inv_s"

Code Examples

Visualize a single Bloch sphere

from bloch_sphere.animate_bloch import do_or_save_animation, AnimState

@do_or_save_animation('my_animation', save=False, fps=20, preview=True)
# Or
#@do_or_save_animation('my_animation', save='gif', fps=20, preview=True)
#@do_or_save_animation('my_animation', save='mp4', fps=20, preview=False)
def animate(state: AnimState):
    state.x_gate()
    state.y_gate()
    state.s_gate()
    state.s_gate()
    ...
    state.wait()  # Pause at the end

Example output animation

Compare two sequences of gates

from bloch_sphere.animate_bloch_compare import main

main('hzh_x', 'h,z,h'.split(','), 'x'.split(','),
     r'& \gate{H} & \gate{Z} & \gate{H} & \qw & \push{=} & & \gate{X} & \qw',
     r'$HZH\ket{\psi}=X\ket{\psi}$',
     mp4=False,
     fps=20,
     preview=True,
)

Or

import drawSvg as draw
import latextools
from bloch_sphere.animate_bloch_compare import render_animation

# Add some extra labels
zero_ket = draw.Group()
zero_ket.draw(latextools.render_snippet('$\ket{0}$', latextools.pkg.qcircuit),
              x=0, y=0, center=True, scale=0.015)
one_ket = draw.Group()
one_ket.draw(latextools.render_snippet('$\ket{1}$', latextools.pkg.qcircuit),
             x=0, y=0, center=True, scale=0.015)
zero_ket_inner = draw.Use(zero_ket, 0, 0, transform='scale(0.75)')
one_ket_inner = draw.Use(one_ket, 0, 0, transform='scale(0.75)')

w = 624*2  # Output width
fps = 20
draw_args = dict(
    w = w/2,
    outer_labels=[
        [(0, 0, 1), (-0.15, 0.13), zero_ket],
        [(0, 0, -1), (0.15, -0.13), one_ket],
    ],
    inner_labels=[
        [(0, 0, 0.8), (0, 0), zero_ket_inner],
        [(0, 0, -0.8), (0, 0), one_ket_inner],
    ],
)

gates1 = 'h,z,h'.split(',')
gates2 = 'x'.split(',')
def func1(state):
    state.draw_args = dict(draw_args)
    state.draw_args['inner_labels'] = []
    state.sphere_fade_in()
    state.apply_gate_list(gates1, final_wait=False)
    state.wait()
    for _ in gates2:
        state.i_gate()
    state.wait()
    state.wait()
    state.sphere_fade_out()
    state.wait()
def func2(state):
    state.draw_args = dict(draw_args)
    state.draw_args['inner_labels'] = []
    state.sphere_fade_in()
    for _ in gates1:
        state.i_gate()
    state.wait()
    state.apply_gate_list(gates2, final_wait=False)
    state.wait()
    state.wait()
    state.sphere_fade_out()
    state.wait()
render_animation('hzh_x_compare', func1, func2,
                 r'& \gate{H} & \gate{Z} & \gate{H} & \qw & \push{=} & & \gate{X} & \qw',
                 r'$HZH\ket{\psi}=X\ket{\psi}$',
                 save='gif',  # False, 'gif', or 'mp4'
                 fps=fps,
                 preview=True,
                 w=w)

Example output animation

Synthesize any gate as Rz, Rx, Rz

Any single-qubit gate can be decomposed into a series of three rotations about fixed axes, most commonly as rotations about Z, X, and Z. See the example code that generated the below animation.

Example output animation

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distributions

No source distribution files available for this release.See tutorial on generating distribution archives.

Built Distribution

bloch_sphere-0.3.0-py3-none-any.whl (11.1 kB view hashes)

Uploaded Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page