QETLAB:Change log/v0.7

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New functions

  • BellInequalityMax: Computes the maximum value of a Bell inequality in a classical, quantum, or no-signalling setting.
  • BreuerState: Generates a Breuer state, which is a specific family of bound entangled states on even local dimensions.
  • DephasingChannel: Produces a (completely or partially) dephasing channel.
  • DickeState: Generates a Dicke state.
  • GHZState: Generates a (generalized) GHZ state.
  • GisinState: Generates a 2-qubit Gisin state.
  • HorodeckiState: Generates a Horodecki state, which is a specific family of bound entangled states in (3 \otimes 3)- and (2 \otimes 4)-dimensional spaces.
  • LocalDistinguishability: Computes the maximum probability of distinguishing quantum states by means of symmetric-extendible measurements.
  • NPAHierarchy: Determines whether or not a set of probabilities satisfy the conditions of the NPA hierarchy, which is a necessary condition for the probabilities to arise from quantum mechanics.
  • PauliChannel: Generates a Pauli channel (i.e., a quantum channel with Kraus operators that are multiples of Pauli operators).
  • RandomProbabilities: Computes a random probability vector, distributed uniformly on the unit simplex.
  • WState: Generates a (generalized) W-state.
  • XORGameValue: Computes the classical or quantum value of a nonlocal XOR game (replaces the old functions XORClassicalValue and XORQuantumValue).
  • helpers/unique_perms: Computes all distinct permutations of a given vector (the same as unique(perms(V),'rows'), but typically faster and less memory-intensive).
  • helpers/update_odometer: Increases the entries of a vector subject to constraints on how large the entries of that vector can be. Useful when you want to have k nested for loops, but k isn't specified beforehand.

Changes to existing functions

  • AbsPPTConstraints: The DIM input argument is now optional, and the LAM input argument can now either be a vector of eigenvalues or a density matrix (it had to be a vector of eigenvalues before).
  • IsAbsPPT: Can now be used directly as a constraint or objective function within other CVX optimization problems.
  • IsPPT: Can now be used directly as a constraint or objective function within other CVX optimization problems.
  • IsPSD: Can now be used directly as a constraint or objective function within other CVX optimization problems.
  • SymmetricExtension: Can now be used directly as a constraint or objective function within other CVX optimization problems.
  • SymmetricInnerExtension: Can now be used directly as a constraint or objective function within other CVX optimization problems.
  • TensorSum: Is now much faster at tensoring together lots (> 20) of sparse vectors.

Removed functions