clargv,zlargv: rename local ABS1 helper to CABSMAX#1220
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langou merged 1 commit intoReference-LAPACK:masterfrom Mar 28, 2026
Merged
clargv,zlargv: rename local ABS1 helper to CABSMAX#1220langou merged 1 commit intoReference-LAPACK:masterfrom
langou merged 1 commit intoReference-LAPACK:masterfrom
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The local ABS1 statement function in CLARGV and ZLARGV does not compute
the usual complex ABS1/CABS1 quantity. It returns
max(abs(real(z)), abs(aimag(z)))
and is used only as a scaling helper in the same algorithmic path as
CLARTG/ZLARTG.
Rename the helper to CABSMAX so that the name matches its actual
behavior and does not suggest CABS1 semantics.
No numerical behavior is changed.
nakatamaho
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…k#1219, #1220) Upstream lapack#1219 renames the local ABS1 statement function to CABS1 in BLAS/LAPACK/CBLAS sources where it computes |Re(z)| + |Im(z)|. Upstream lapack#1220 further handles Clargv/Zlargv, whose local ABS1 helper actually computes max(|Re(z)|, |Im(z)|) and must not be renamed to CABS1; rename it to CABSMAX instead. Apply both to the MPLAPACK C++ codebase: - Add patch-cabs1_unification and patch-cabsmax to external/lapack/Makefile.am. - Update mplapack/reference/Clargv.cpp: add inline cabsmax(), replace the two cabs1() call sites with cabsmax(). - Regenerate fable/3.12.1/lapack/patch-Clargv.cpp: introduce cabsmax inline helper and drop the erroneous lvalue ABS1 statement removal. - Remove now-superfluous patches from fable/patch_lapack_3.12.1.sh: Cggev, Cggev3, Cggevx, Ctgevc, Clags2, Chgeqz were previously patched for ABS1->CABS1 and are subsumed by lapack#1219. - Remove from fable/patch_lapack_test_3.12.1.sh: Cdrges, Cdrges3, Cget52 for the same reason. - Simplify patch-Cdrgsx.cpp: the abs1->cabs1 hunks are no longer needed after lapack#1219. No numerical change. cf. Reference-LAPACK/lapack#1220 Reference-LAPACK/lapack#1219
langou
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Thanks! Yes, that'll avoid confusion for whoever thinks they know what CABS1 is. CABSMAX is a good choice of name WRT CABS1. Thanks!
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The local ABS1 statement function in CLARGV and ZLARGV does not compute the usual complex ABS1/CABS1 quantity. It returns
and is used only as a scaling helper in the same algorithmic path as CLARTG/ZLARTG.
Rename the helper to CABSMAX so that the name matches its actual behavior and does not suggest CABS1 semantics.
No numerical behavior is changed.
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