unitaryfund / qrack

Comprehensive, GPU accelerated framework for developing universal virtual quantum processors
https://qrack.readthedocs.io/en/latest/
GNU Lesser General Public License v3.0
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QBDT vs. state vector threshold #908

Closed WrathfulSpatula closed 3 years ago

WrathfulSpatula commented 3 years ago

For use under QUnit, (or in general,) QBinaryDecisionTree now has a switch-over threshold from state vector as a more efficient alternative for narrower widths. To recover the original behavior, set the environment variable QRACK_BDT_THRESHOLD to 0. By default, binary decision tree methods will engage in QBinaryDecisionTree instances that are 31 qubits or greater in wifth, (equivalent to a QRACK_BDT_THRESHOLD of 30).