Code and data for A metric-compatible positivity-preserving compact scheme for degenerate time-space fractional reaction-diffusion with variable delay

This record contains the code and numerical data accompanying the manuscript “A metric-compatible positivity-preserving compact scheme for degenerate time-space fractional reaction-diffusion with variable delay.” The archive includes the uniform-grid reference solver, nonuniform Alikhanov time stepping, causal accepted-history delay reconstruction, inverse-diffusion metric projection, clipping comparisons, and direct-implicit baseline implementations. It provides 20 experimental CSV files containing 988 records and 182 compressed trajectory files, including 160 trajectories with analytical reference arrays and 22 unforced numerical-reference trajectories. Figure-generation scripts, environment records, a data dictionary, a figure-and-table source map, and read-only verification programs are included. The numerical studies cover temporal and spatial convergence, oscillatory and discontinuous delays, weak-startup behavior, projection activity, clipping error amplification, and computational costs. Fixed-candidate error transfer is distinguished from independently advanced trajectory accuracy, and operator-action timings are distinguished from complete-solver runtimes. Benchmark coordinates are nondimensional; computational timings use the units specified in the accompanying files. This record archives the research materials associated with the manuscript and does not include peer-review reports or correspondence. Licensing: Author-owned source code is licensed under the MIT License.Author-owned numerical data, figures and documentation are licensed underCreative Commons Attribution 4.0 International (CC BY 4.0).Third-party materials, if any, retain their original licenses and notices.The scope of each license is specified in RIGHTS.md.