Change Log¶

Source code for previous releases can be found at https://github.com/grey-area/qcircuits/releases.

v0.6.0, 2021/01/03¶

Added purification of density operators.
Added reduced density operators for states and density operators.
Added convenience method for computing density operator from single pure state.
Added method for computing computational basis measurement probabilities from density operators.
More efficient partial trace for density operators.
Tests for the above.

Added density operators, along with operator application, qubit permutation, and measurement functionality.

Supports Python 3.4.3
Added phase gate, pi/8 gate.
Added rotation gates.
Can now add, subtract, negate, scalar-multiply states (and operators).
State re-normalization is now done after operator application and measurement.
New __str__ and __repr__ methods of operators and states.
Can now get Kronecker product column vector/matrix representations of states and operators, and construct them from those representations.
Can now compute the Schmidt number of a composite state.
Can now permute the incoming and outgoing qubits of an operator in the same way as can be done to states.
Can now apply d-qubit operators to n-qubit operators where n>d by supplying the indices of the higher-rank operator that the lower-rank operator will apply to. Unified implementation with implementation of applying operator to larger state, simplifying the __call__ method of Operator.

Added methods to permute or swap qubits in a state
There is now a flag when measuring the state that determines whether or not the measured qubits are removed from the state vector
Added a method to get the adjoint/inverse of an operator
Can now measure an arbitrary number of bits at once, in any order
Measuring a state now modifies it, rather than returning the post-measurement state
Operators can now be applied to qubits in arbitrary order
Added Toffoli gate
Loosened requirements to >python3.4.3 and >= numpy1.11.3
Added unit tests
Added documentation