Version 1.1 Update Notes

The v1.1 release line covers numerical failure handling, vortex-example stability, macOS portability, and tutorial validation, preserving the existing input format and solver interfaces wherever possible.

Version 1.1

• The 3D vortex example recomputes its nonlinear right-hand side after startup extrapolation and uses a local final-step size without modifying the global time step.
• Periodic quadratic products use a 2/3 Fourier mask. An optional bounded tail-energy spectral vanishing-viscosity (SVV) filter can damp populated high modes; separate feedback states are maintained for the toroidal and poloidal potentials.
• The mapped far-field coefficient is removed after each vortex step, and all MPI ranks collectively abort if either potential becomes non-finite.
• Laplacian inversion null modes, transformed-input handling, FFT chopped-region checks, and dense-by-band storage bounds are corrected.
• Invalid chopping sizes, unsupported hyperviscosity powers, enabled hyperviscosity with a non-positive coefficient, malformed SVV controls, and invalid output intervals now fail during input parsing.
• Homebrew GNU Fortran is supported without the Linux-only -mcmodel=medium flag, and external libraries can be built from any working directory with explicit compiler choices, as in FC=gfortran CC=cc BUILD_JOBS=2 ./external/CMake_build.sh.
• Documented and notebook MPI commands use portable mpirun -n, and the validation tool adds OpenMPI-only flags at runtime only when they are required, so compatible MPICH installations can also run the tutorials.
• Added the tutorial validation gate, which checks six notebooks, twelve documentation pages, and 13 documented executable paths on the requested MPI rank count, runs matched low-viscosity SVV-off and SVV-on vortex cases and requires their final fields to differ, and requires representative zero-coefficient hyperviscosity, unsupported-power, and invalid-SVV inputs to fail nonzero. Notebook cells are executed as well when nbformat, nbclient, and a Python kernel are installed. CI repeats the gate with GNU Fortran bounds checking, backtraces, and floating-point traps enabled.
• Known limitation: exact 2/3 de-aliasing applies to the periodic azimuthal and axial directions only. The mapped radial quadratic product is not over-integrated; SVV can damp its high-mode tail but cannot undo radial energy already aliased into retained modes.
• Known limitation: the saved vortex sample field is vorticity magnitude, not a kinetic-energy spectrum. A velocity-spectrum diagnostic and resolution study are required before assessing a -5/3 inertial-range slope.
• Known limitation: with periodic 2/3 masking, svv_cutoff = 0.75 primarily targets the mapped radial tail. Use a cutoff below approximately 2/3 if the highest retained periodic bands should also participate, and retune the target and strength for the chosen Reynolds number and resolution.
• Known issue, fixed in v1.1.1: the documented gate command python3 tools/validate_tutorials.py --ranks 2 always failed on this version, because wave_propagation_1d stops unless given exactly one process and the gate passed its global rank count to every application. On v1.1 itself, use --ranks 1.

Version 1.1.1

• Fixed the tutorial validation gate, which could not pass above one MPI rank. wave_propagation_1d solves a purely radial problem, so the rank owning the radial direction must own all of it, and the program stops deliberately when launched on more than one process. The gate passed its global --ranks value to every application, so that case aborted at any rank count above one. The rank count is now overridden for that application alone, and the twelve remaining tutorials keep their parallel coverage.
• Corrected CITATION.cff, which recorded the v1.0 Zenodo DOI together with a version string and release date matching no tag.
• This maintenance patch did not change the numerical solver, input format, or documented tutorial commands; the sources under src/ are identical to v1.1.

Version 1.1.2

• Combined the 1.1 patch update notes into this single page, matching the v1.0.x convention of one page per major-minor line, and aligned its structure and wording with the v1.0 page.
• Updated the validation gate’s documentation inventory and the Update Notes index to match the merged page.
• This maintenance patch did not change the numerical solver, input format, or documented tutorial commands; the sources under src/ are identical to v1.1.

Version 1.1.3

• CITATION.cff now records the concept DOI rather than a version DOI. A version DOI is minted from the release it identifies, so no tag can contain its own; the concept DOI always resolves to the newest version and is correct in every release. The version DOIs for v1.1, v1.1.1 and v1.1.2 are listed under identifiers.
• This maintenance patch did not change the numerical solver, input format, or documented tutorial commands; the sources under src/ are identical to v1.1.