Methods & Data Dictionary

Pathfinder · how the numbers are made, and what every column means
snapshot 2026-08-01 11:52
34m ago · schema v3

Every figure on these boards comes from one blind process — a walk that steps to a random unvisited neighbour until it traps itself — measured once and aggregated cheaply. This page is the reference: the pipeline that turns raw traces into a snapshot, a dictionary of every per-path measure, the science each panel tests, and a live look at the current snapshot with a link to download it.

I

The pipeline

Nothing here touches the path library or the network at page-load: a scheduled builder does all the reading and writes one JSON snapshot, and every board renders only that file. The builder is incremental — each new .wrd is analysed exactly once into an append-only index — so even a multi-million-path library is processed once, ever.

Library
*.wrd traces — full (x, y) traces of the kept "interesting" walks
Index pass
each new file measured into path_stats.csv (≈50 columns/path)
Aggregate pass
streams the index (+ population & fleet logs) into path_stats_summary.json
Boards
these pages render the JSON only — instant, offline, read-only

Three sources, three provenances. LIB the kept .wrd library — geometry-rich, but only the tail (length ≥ 3000 or radius ≥ 300). POP combined histograms over every walk ever run — the uncensored truth for means and exponents. LOG the per-machine performance.log — throughput and luck. Any full-population claim must come from POP; the library alone is a censored sample.

II

Per-path data dictionary

One row per kept path in path_stats.csv. Each column is a single linear pass over the trace (the convex hull is O(N log N); the sealed-chamber flood fill is bounded). Everything the boards show derives from this table plus the population and fleet logs.

Table 1. The measures computed for every walk, grouped by theme.
ColumnMeaning
Identity
fileFilename Length_Serial_Client.wrd
serial / clientThe path's serial number and the machine that found it
mtimeWhen the file was written (used for growth and record history)
familyMarathoner (N≥3000), Voyager (R_max≥300), Legend (both), or other
Size & displacement
lengthSteps taken, N (points − 1) — the headline number
end_rEnd-to-end distance R from origin to the death point
manhattan|dx|+|dy| at death
max_rFarthest radius the walk ever reached — the Voyager criterion
rgRadius of gyration — the polymer-physics size measure
bbox_w / bbox_h / aspectBounding-box width, height and long/short ratio
hull_area / hull_perim / hull_vConvex-hull area, perimeter and vertex count
fill_bbox / fill_hullPoints per unit bounding-box / hull area — coil density
fractal_dBox-counting dimension of the trace (2-D SAW theory: 4/3)
asphericityGyration-tensor shape, 0 = disc … 1 = rod
Direction & turning
d0 … d7Counts of each of the 8 step directions
diag_fracFraction of steps that were diagonal (cover √2)
longest_runLongest unbroken straight run, in steps
chiralityNet signed turning (+ = CCW, − = CW)
winding_deg / orbitsTotal angle wound about the origin, and full turns
turn_entropyShannon entropy of the turn-angle histogram
reversal_rate / repeat_fracShare of turns ≥90°, and share that repeat the heading
drift_mag / drift_deg / death_degCentroid drift magnitude & bearing; death bearing
Death & constraint
self_contactsTimes the walk brushed its own trail and survived
choice_entropyMean log₂(free neighbours) — how constrained the walk was
enclosed_areaUnvisited cells sealed into chambers at death (−1 if skipped)
free_m10 / free_m50 / free_m100Free neighbours 10/50/100 steps before the trap
Origin & tempo
esc50 / esc100 / esc200 / esc300First step to reach radius 50/100/200/300 (−1 = never)
closest_returnNearest approach to home after first passing radius 100
outward_biasFraction of steps that increased the radius
tortuosityN ÷ R — steps spent per cell of net progress
peak_fracWhere R_max happened, as a fraction of the walk
III

Methods the panels test

Flory exponent ν
Fit ⟨R²⟩ ∼ N across length bins. The 2-D self-avoiding-walk value is ν = 3/4 exactly (Nienhuis 1982); kinetic-growth walks are believed to share it asymptotically.
Fractal dimension D
Mean box-counting slope of a trace; theory D = 1/ν = 4/3.
Asphericity
From the gyration-tensor eigenvalues, ((λ₁−λ₂)/(λ₁+λ₂))²; a known universal mean for 2-D SAWs.
Winding-angle law
Variance of the angle wound about the origin grows ∝ ln N (Duplantier & Saleur 1988).
First-passage scaling
Median step to reach radius r grows as r1/ν = r4/3.
Asphyxiation curve
Ensemble-mean free neighbours 100/50/10 steps before the trap — the universal shape of dying.
Mean trapping length
The [POP] mean walk length. The 4-direction lattice value is ≈70.7 (Hemmer & Hemmer 1984); the 8-direction constant has no published figure and is measured here.
RNG integrity
Chirality must split 50/50 (binomial p) and the 8 step directions must be equiprobable across the ensemble (χ² vs uniform); the roses must be round.
Correlation matrix
Pearson r between the curated measures, from streamed sums, sums-of-squares and cross-products.
Shape space
PCA of the correlation matrix (a Jacobi eigen-decomposition); a reservoir sample of paths is projected onto the top two components. The nearest twin is the closest pair in standardised descriptor space.
Record history
Because the index is written oldest-first, a forward pass with running maxima recovers when each record fell; for i.i.d. draws the count grows as ln n + γ and the next break waits ~n paths.
The bestiary
Each walk is placed into one personality species by priority rules on orbits, outward bias, straight-run length, hull fill, reach and tortuosity, using library-adaptive cut-offs.
Rarity / Path of the Day
Mean absolute z-score across length, reach, gyration, tortuosity and hull area over the recent window.
IV

This snapshot

schema
v3
compiled
2026-08-01 11:52:15 (34m ago)
library
45.5K kept paths

Blocks present in the current snapshot:

census Counts by family and client
distributions Per-measure histograms
length_profile Paths-per-length (library + population)
records Hall-of-fame record holders
records_history When each record fell (vs ln n)
roses Drift / death / step / frontier roses
symmetry RNG-integrity χ² and chirality
science Flory ν, winding, asphyxiation, first-passage
correlation Pearson-r matrix of the measures
families_detail Per-family summary
growth Library growth over time
shape_map PCA shape space + nearest twin
bestiary Personality-species classification
population Uncensored [POP] truths
fleet Per-machine luck [LOG]
coverage World coverage heat grid
thumbnails Embedded specimen traces

⭳ Download the raw snapshot (JSON) everything on every board, in one file

Reference for the statistics builder and the reading boards. The dictionary mirrors the index schema. All measurement, no decoration.