Pass correct off-diagonal length to SymTridiagonal in expT! call - #277
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Pass correct off-diagonal length to SymTridiagonal in expT! call#277KristofferC wants to merge 1 commit into
SymTridiagonal in expT! call#277KristofferC wants to merge 1 commit into
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The j×j Lanczos tridiagonal needs only β[1:j-1]; the extra β[j] was tolerated and ignored by SymTridiagonal, but Julia 1.14 throws a DimensionMismatch (JuliaLang/LinearAlgebra.jl#1569). The shorter form is accepted on all Julia versions. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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expT!SymTridiagonal in expT! call
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The Lanczos loop in the error-estimate variant of
expv!passes@view(β[1:j])toexpT!, one element more than thej×jtridiagonal needs —β[j]is the residual norm, not part ofT_j.SymTridiagonalused to ignore the extra element (LAPACK convention), but on Julia 1.14 it throwsDimensionMismatch(JuliaLang/LinearAlgebra.jl#1569), which currently breaks dependents in PkgEval at precompile time, e.g. FirstPassageTools and MRFingerprintingRecon.Passing
β[1:j-1]is accepted on all Julia versions (no compat bound changes needed, safe to backport), andexpT!only usesβthrough theSymTridiagonal, so behavior on ≤1.13 is unchanged.🤖 Generated with Claude Code