Guides

Task-oriented documentation for each of propaq's subsystems. Each guide assumes you have read Core concepts.

• Circuits and gates

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  Converting Qiskit and Cirq circuits, the native gate basis, the transpile-based fallback, and registering fast paths for custom gates.

• Truncation

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  The truncator pipeline: weight, coefficient, frequency truncators, and how flushes are triggered.

• Noise models

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  Built-in uniform damping, Python-defined models, and how noise interacts with Clifford deferral.

• Surrogate propagation

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  Compiling a parameterized circuit once and evaluating it for many parameter assignments, plus model persistence.

• Extrapolation

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  Zero-noise and zero-cutoff extrapolation to estimate the ideal expectation value from a sweep of runs.

• Streaming and I/O

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  Saving and reloading term sums, and lazy streaming for results too large to hold in memory.

• Hybrid simulation

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  Splitting a circuit between a Heisenberg half and a Schrödinger half, and contracting a propagated observable against an MPS in one native call.

• Logging and profiling

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  JSONL event logs, the parser, and what to look at when a run is slower or less accurate than you expect.

• Native plugins

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  Writing noise models and truncation policies in C, Rust or AOT-compiled Julia against propaq's plugin ABI.