Flagship changes:

• Added support for representing and verifying stabilizer flows (stim.Flow, stim.Circuit.has_flow, stim.Circuit.detecting_regions)

Notable changes:

• New top-level methods/types:
  • Added stim.Flow class for representing stabilizer flows
  • Added stim.target_pauli
  • Added stim.target_combined_paulis
  • Added stim.PauliStringIterator
• New stim.Circuit methods:
  • Added stim.Circuit.decomposed
  • Added stim.Circuit.detecting_regions
  • Added stim.Circuit.to_qasm
  • Added stim.Circuit.has_flow
  • Added stim.Circuit.has_all_flows
  • Added stim.Circuit.shortest_error_sat_problem
  • Added stim.Circuit.likeliest_error_sat_problem
• New stim.GateData methods:
  • Added stim.GateData.{__eq__,__ne__,__repr__,__init__,__str__}
  • Added stim.GateData.flows
  • Added stim.GateData.generalized_inverse
  • Added stim.GateData.inverse
• New stim.PauliString methods:
  • stim.PauliString.__init__ now allows sparse syntax (like stim.PauliString("-X50*Z99"))
  • Added stim.PauliString.iter_all
  • Added stim.PauliString.pauli_indices
  • Added stim.PauliString.weight
  • Sped up stim.PauliString.{after,before} by over 10x
• New stim.Tableau methods:
  • Added stim.Tableau.to_circuit("graph_state")
  • Added stim.Tableau.to_circuit("mpp_state")
  • Added stim.Tableau.to_circuit("mpp_state_unsigned")
  • Added stim.Tableau.to_stabilizers
  • Sped up stim.Tableau.from_stabilizers by over 200x
• New stim.FlipSimulator methods:
  • Added stim.FlipSimulator.broadcast_pauli_errors
• New gates:
  • Added CZSWAP gate (with alias SWAPCZ)
  • Added SPP gate (generalized S gate that applies to Pauli products)
  • Added SPP_DAG (inverse of SPP)
• Added sinter.FusionBlossomCompiledDecoder, speeding up decoding with fusion blossom
• Added sinter plot --ymax command line argument
• stimcirq now converts PAULI_CHANNEL_2 into cirq's native asymmetric channel
• Added Bloch Rotation (Euler angles) to gate documentation
• Added prebuilt wheels for python 3.12
• Tweaked sinter plot's marker/color ordering to increase how many curves are needed to get two curves that look similar

Notable bug fixes:

• Fixed sinter plot --xaxis only applying to one subplot, instead of all subplots
• Fixed build-from-source not working on IBM PowerPC
• Fixed HERALDED_PAULI_CHANNEL_1 targeting the wrong qubits (this fix was also backported to 1.12.1)
• Fixed stim.Circuit.explain_dem_errors not supporting all gates
• Fixed crumble not allowing e and q to repeatedly move between layers when held down
• Fixed crumble not falling back to an emulated clipboard when clipboard permissions weren't granted

Special thanks to this release's contributors:

@fdmalone
@markturner289
@mmcewen-g
@nickdgardner
@noajshu
@tomirendo