Release 0.8.1

What's Changed

Added

• Qx.draw_histogram/2, replacing Qx.histogram/2. The new name
  matches the rest of the Qx.draw* family (Qx.draw/2,
  Qx.draw_counts/2, Qx.draw_bloch/2, Qx.draw_state/2).

• Qx.StateInit.bell_state_vector/2 and Qx.StateInit.ghz_state_vector/2,
  the canonically-named state-vector constructors. The _vector suffix
  names the return type, disambiguating these from the circuit-returning
  Qx.bell_state/1 and Qx.ghz_state/0.

Deprecated

• Qx.StateInit.bell_state/2 and Qx.StateInit.ghz_state/2 in favour of
  the _vector-suffixed names above. Both keep working through 0.8.x —
  they delegate verbatim to the new functions — and are scheduled for
  removal in v0.9.

Changed

• Qx.Patterns.bell_state_circuit/1 and Qx.Patterns.ghz_state_circuit/1 are
  now @doc false. The documented entry points for these circuits are the
  Qx.bell_state/1 and Qx.ghz_state/1 facades, which delegate to them; the
  Patterns functions remain callable (no API change), they just no longer
  appear as separate HexDocs pages.

• Public API surface is now declared explicitly (no API change). Iron
  Law #6 now guards the modules README and the tutorials actually treat as
  primary surface: Qx.Qubit, Qx.Register, Qx.StateInit, Qx.Patterns,
  Qx.Math, Qx.Hardware, Qx.Hardware.Config, Qx.Export.OpenQASM, and
  Qx.Draw (alongside the previously-declared Qx, Qx.QuantumCircuit,
  Qx.Operations, Qx.Simulation, Qx.SimulationResult, Qx.Behaviours.*).
  Internal helpers no longer appear in the published docs — Qx.Validation,
  the Qx.Draw.SVG.* and Qx.Export.OpenQASM.* sub-modules, and
  Qx.Hardware.Ibm / Qx.Hardware.Portal are now @moduledoc false. Every
  function stays callable; the typed Qx.*Error exceptions remain part of the
  public contract.

• Typed errors for the last raw ArgumentErrors in Qx.Validation
  (plan: iron-law-7-followon). Completes the Iron Law #7 pass begun
  in 0.8.0. Qx.Validation now raises typed exceptions instead of
  ArgumentError:

  • a non-numeric gate parameter raises the new Qx.ParameterError
    (carries the offending :value);
  • duplicate qubit indices raise Qx.QubitIndexError;
  • a state-vector shape mismatch raises Qx.StateShapeError.

  Observable on the public rotation/phase gates Qx.rx/3, ry/3,
  rz/3, u/5, cp/4, crx/4, cry/4, crz/4 (and their
  Qx.Operations equivalents): a non-numeric angle now raises
  Qx.ParameterError rather than ArgumentError. Code rescuing the
  old ArgumentError must be updated.

• Typed errors across the rest of the public surface
  (plan: iron-law-7-sweep). Clears the remaining raw ArgumentErrors
  and one stray FunctionClauseError from the public API, finishing the
  Iron Law #7 work begun in 0.8.0. Two new exceptions:

  • Qx.RegisterError — register construction input (an empty list, a
    malformed qubit, or a renderer handed a non-register); carries a
    :reason.
  • Qx.BasisError — a computational basis value that is not 0 or 1;
    carries the offending :value.

  Retyped surfaces — code rescuing the old ArgumentError /
  FunctionClauseError must be updated:

  • Qx.Register.new/1 and Qx.Register.from_basis_states/1 →
    Qx.RegisterError / Qx.BasisError;
  • the register two-qubit distinctness gates (cx, cz, cy,
    ccx, swap, iswap, cswap, and the controlled-target gates)
    → Qx.QubitIndexError;
  • Qx.Qubit.from_basis/1 → Qx.BasisError;
  • Qx.Draw.* plots and Qx.Draw.Tables.render/2 with an invalid
    :format → Qx.OptionError; a non-register input →
    Qx.RegisterError;
  • Qx.Export.OpenQASM.to_qasm/2 with an invalid :version →
    Qx.OptionError;
  • Qx.Draw.circuit/2 on a malformed circuit →
    Qx.QubitCountError / Qx.GateError / Qx.QubitIndexError /
    Qx.ClassicalBitError;
  • Qx.u/5 with an out-of-range qubit now raises
    Qx.QubitIndexError instead of FunctionClauseError, matching
    rx/ry/rz/cp.

Deprecated

• Qx.histogram/2 is deprecated. Use Qx.draw_histogram/2 instead.
  Emits a compile-time warning and is hidden from ExDoc. Scheduled
  for removal in v1.0.

Installation

Add to your mix.exs:

def deps do
  [
    {:qx_sim, "~> 0.8.1"}
  ]
end

Documentation

• Hex.pm: https://hex.pm/packages/qx_sim/0.8.1
• Docs: https://hexdocs.pm/qx_sim/0.8.1