FA-90947 / Quantum circuit simulation / Member archive

Pauli expectation ignores the state norm · case 02

For 3|0> + 4|1>, <Z> is reported as -7 instead of -0.28.

Member previewVariant 2 · 3 implementations · 7 checks per implementation

Case contract

Input [n, amps, pauli]; pauli is an n-character string over I,X,Y,Z whose rightmost character acts on qubit 0 (LSB). Return the real expectation <psi|P|psi>/<psi|psi> rounded to 6 decimals. Errors: "length-mismatch", "bad-pauli" (any character outside uppercase IXYZ).

Why this case matters

Pauli expectation values are the observable layer of variational algorithms; string-order or phase slips bias every energy estimate.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: random expectation 0	`5.298027`	`1.0`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.