perf: hoist loop-invariant substitution out of JacobianSpectrum - #146
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The harmonic of a uv pair depends only on the pair, not on the eigenvalue, but
it was recomputed inside the eigenvalue loop, rebuilding `Dict(solution_dict)`
and running a symbolic `substitute` on every (eigenvalue, pair) iteration.
Profiling the lab frame Jacobian response showed that loop dominated by
`Dict{Num}` lookups, `isequal(::Num, ::Num)` and SymbolicUtils hash consing.
Substituting once per pair up front cuts the benchmark from 2.30/2.46 ms to
1.82/1.96 ms and drops allocations from 11798 to 10809, restoring parity with
the pre-Symbolics-7 stack, which measured 1.824 ms on the same machine.
Bumps HarmonicSteadyState to v0.5.1.
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The harmonic of a uv pair depends only on the pair, not on the eigenvalue, but
JacobianSpectrumrecomputed it inside the eigenvalue loop. Every(eigenvalue, pair)iteration rebuiltDict(solution_dict)and ran a symbolicsubstitute.Profiling
get_jacobian_responseshowed that loop dominated byDict{Num}lookups,isequal(::Num, ::Num)and SymbolicUtils hash consing, withsubstitutethe single most expensive primitive at ~530 ns per call.Substituting once per pair up front, and hoisting
_get_uv_pairsand_get_asas well:Measured full suite, same machine, alternating runs. For reference the pre-Symbolics-7 stack measured 1.824 ms in the same condition, so this restores parity.
Behaviour is unchanged: the substituted harmonic never depended on the eigenvalue.
Bumps to v0.5.1.