rand.random_states

Generates random quantum states using Qiskit.

Functions

random_states(n, d[, seed])

Generate a list of random quantum states.

Module Contents

rand.random_states.random_states(n, d, seed=None)

Generate a list of random quantum states.

This function generates a list of quantum states, each of a specified dimension. The states are valid quantum states distributed according to the Haar measure.

Examples

Generating three quantum states each of dimension 4.

from toqito.rand import random_states

states = random_states(3, 4)
print(f"length of states is {len(states)}")

print(f"Shape of each state vector: {states[0].shape}")

for idx, state in enumerate(states):
   print(f"\nState {idx}:")
   print(state)

length of states is 3
Shape of each state vector: (4, 1)

State 0:
[[-0.3911973 -0.2439141j ]
 [-0.40019527+0.13556597j]
 [ 0.04182829+0.15055571j]
 [ 0.29554738+0.70510376j]]

State 1:
[[-0.16955403-0.17896464j]
 [ 0.08536334+0.50378187j]
 [-0.31602644-0.57031278j]
 [ 0.29099813+0.41028128j]]

State 2:
[[ 0.06835308-0.41898005j]
 [-0.12370692-0.77946159j]
 [ 0.01926438-0.21155522j]
 [ 0.13519676-0.36539691j]]

It is also possible to pass a seed to this function for reproducibility.

from toqito.rand import random_states

states = random_states(3, 4, seed=42)

for idx, state in enumerate(states):
   print(f"\nState {idx}:")
   print(state)


State 0:
[[ 0.13830446+0.0299699j ]
 [-0.47202619+0.51163029j]
 [ 0.34061349+0.21219233j]
 [ 0.42690188-0.39001418j]]

State 1:
[[-0.71489214+0.1351165j ]
 [-0.47714049-0.35135073j]
 [ 0.04684288+0.32187898j]
 [-0.11587661-0.01829369j]]

State 2:
[[-0.00827473-0.0910465j ]
 [-0.42013238-0.33536439j]
 [ 0.43311201+0.60211343j]
 [ 0.38307005-0.07610726j]]
Parameters:

  • n (int) – int The number of random states to generate.

  • d (int) – int The dimension of each quantum state.

  • seed (int | None) – int | None A seed used to instantiate numpy’s random number generator.

Returns:

list[numpy.ndarray] A list of n numpy arrays, each representing a d-dimensional quantum state as a column vector.

Return type:

list[numpy.ndarray]