docs: restructure the 3.13.0 post around themes and use cases

- deeper technical detail and code in the eight themes; pull request
  numbers move to the appendix, timeline steps are labelled by theme
- comparison with other libraries by use case, as heatmaps per
  platform, with validation levels and the caveats next to the results
- appendix: test files, all 182 suite rows with a histogram, timeline
  steps, algorithmic fixes, per-file tables, behaviour changes, setup,
  pull requests by theme

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/scripts/figures/perf_blog_tables.py

@@ -0,0 +1,67 @@
+"""Prints the tables of Appendix E of home/blog/how_3_13_0_got_faster.md (comparison with other libraries) as Markdown,
+from data/perf_usecases_<platform>.json, which tests/benchmarks/json_view/others/summarize.py --json writes.
+
+Usage: python3 scripts/figures/perf_blog_tables.py <platform> [title]
+"""
+import json
+import sys
+from pathlib import Path
+
+from perf_blog import normalize_usecases
+
+HERE = Path(__file__).resolve().parent
+FILES = [("twitter", "`twitter.json`"), ("citm_catalog", "`citm_catalog.json`"), ("canada", "`canada.json`"),
+         ("jeopardy", "`jeopardy.json`"), ("status", "one status (2.5 KB)")]
+USE_CASES = [("validate", "validate"), ("sum", "sum"), ("select", "select"), ("edit", "edit"), ("minify", "minify"),
+             ("write", "write")]
+NAMES = {"nlohmann json_document": "nlohmann/json `json_document`", "nlohmann json": "nlohmann/json `json`",
+         "sonic-rs": "sonic-rs (Rust)", "simd-json": "simd-json (Rust)", "serde_json": "serde_json (Rust)"}
+MARK = {"no UTF-8": "U", "partial": "P"}
+
+
+def fmt(us):
+    if us >= 10000:
+        return "{:,.0f}".format(us)
+    if us >= 100:
+        return "{:,.0f}".format(us)
+    return "%.1f" % us
+
+
+def table(data, uc, indent):
+    files = [f for f, _ in FILES if f in data.get(uc, {})]
+    libs = list(data[uc][files[0]].keys())
+    jd = lambda f: data[uc][f]["nlohmann json_document"]["best"]["us"]
+    libs.sort(key=lambda l: sum(((data[uc][f][l]["best"] or data[uc][f][l]["best_any"])["us"] / jd(f)) for f in files))
+    head = "| library | variant | " + " | ".join(n for f, n in FILES if f in files) + " |"
+    rows = [head, "| --- | --- | " + " | ".join("--:" for _ in files) + " |"]
+    for lib in libs:
+        best = [data[uc][f][lib]["best"] for f in files]
+        anyv = [data[uc][f][lib]["best_any"] for f in files]
+        names = sorted({b["variant"] for b in best if b} | {a["variant"] + " [%s]" % MARK[a["level"]] for b, a in zip(best, anyv) if a["level"] in MARK and (not b or a["us"] < b["us"])})
+        cells = []
+        for b, a in zip(best, anyv):
+            c = fmt(b["us"]) if b else "–"
+            if a["level"] in MARK and (not b or a["us"] < b["us"] * 0.97):
+                c += " (%s %s)" % (MARK[a["level"]], fmt(a["us"]))
+            cells.append(c)
+        bold = "**%s**" if lib == "nlohmann json_document" else "%s"
+        rows.append("| %s | %s | %s |" % (bold % NAMES.get(lib, lib), ", ".join(names), " | ".join(cells)))
+    return "\n".join(indent + r for r in rows)
+
+
+def main():
+    platform = sys.argv[1]
+    data = json.load((HERE / "data" / ("perf_usecases_%s.json" % platform)).open())
+    data = normalize_usecases(data)   # the same choices as the figure
+    out = []
+    for uc, label in USE_CASES:
+        if uc not in data:
+            continue
+        out.append("**%s**\n" % label)
+        out.append(table(data, uc, ""))
+        out.append("")
+    print("\n".join(out))
+
+
+if __name__ == "__main__":
+    main()