31:Taad,function drawCoords(coords) { const height = 400; const ctx = DOM.context2d(width, height); let minX = null; let minY = null; let maxX = null; let maxY = null; coords.forEach(([x, y]) => { if (minX == null || x < minX) minX = x; if (minY == null || y < minY) minY = y; if (maxX == null || x > maxX) maxX = x; if (maxY == null || y > maxY) maxY = y; }); const padding = 0.1; const normalize = (x, y) => [ (((x - minX) / (maxX - minX)) * (1 - padding * 2) + padding) * width, (((y - minY) / (maxY - minY)) * (1 - padding * 2) + padding) * height ]; ctx.strokeStyle = 'black'; coords.forEach(coord => { ctx.beginPath(); ctx.arc(...normalize(...coord), 2, 0, 2 * Math.PI); ctx.stroke(); }); // Identify the track const track = identifyTrack(coords); for (const segment of getLineSegments(coords)) { ctx.strokeStyle = 'rgba(255, 0, 0, 0.15)'; ctx.beginPath(); ctx.moveTo(...normalize(...segment.p1)); ctx.lineTo(...normalize(...segment.p2)); ctx.stroke(); } // Draw parallel segment lines and their midpoints const parallelSegments = track.parallelSegments; parallelSegments.forEach(parallelSegment => { ctx.strokeStyle = 'rgba(0, 0, 0, 0.15)'; ctx.beginPath(); ctx.moveTo(...normalize(...parallelSegment.mid[0])); ctx.lineTo(...normalize(...parallelSegment.mid[1])); ctx.stroke(); }); const arcDrawIterations = 50; if (track.arc != null) { // Draw winning arc ctx.strokeStyle = 'green'; track.arc.mid.forEach(point => { ctx.beginPath(); ctx.arc(...normalize(...point), 2, 0, 2 * Math.PI); ctx.stroke(); }); const project = (coord, radius, top, percent) => { const baseDegrees = track.arc.bearingDegrees + (top ? 90 : -90); return destinationMeters(coord, baseDegrees + 180 * percent, radius); }; ctx.strokeStyle = 'orange'; ctx.lineWidth = 5; ctx.beginPath(); ctx.moveTo( ...normalize(...project(track.arc.mid[0], track.arc.radii[0], true, 0)) ); for (let i = 1; i <= arcDrawIterations; i++) { ctx.lineTo( ...normalize( ...project( track.arc.mid[0], track.arc.radii[0], true, i / arcDrawIterations ) ) ); } for (let i = 0; i <= arcDrawIterations; i++) { ctx.lineTo( ...normalize( ...project( track.arc.mid[1], track.arc.radii[1], false, i / arcDrawIterations ) ) ); } ctx.lineTo( ...normalize(...project(track.arc.mid[0], track.arc.radii[0], true, 0)) ); ctx.stroke(); } return ctx.canvas; }32:T61f,function identifyTrack(coords) { // Store max overall fitness let overallBest = null; let overallBestFitness = 0; // Store all parallel segments collected const parallelSegments = []; // Tree helpers const nCoords = coords.length; const tree = makeTree(coords); for (const parallelSegment of identifyParallelSegments(coords)) { parallelSegments.push(parallelSegment); // Iterate all new best fitnesses to break on earliest/best match for (const { topBest, bottomBest, topFitness, bottomFitness } of arcFitness( parallelSegment, nCoords, tree )) { // See if we can store a new best fitness if (topBest != null && bottomBest != null) { // Best fitness is the min of top and bottom fitnesses const bestFitness = Math.min(topFitness, bottomFitness); if (bestFitness > overallBestFitness) { // Set new best fitness overallBest = { mid: [topBest.point, bottomBest.point], bearingDegrees: turf.bearing( turf.point(topBest.point), turf.point(bottomBest.point) ), radii: [topBest.radius, bottomBest.radius], fitness: [topBest.fitness, bottomBest.fitness] }; } if (bestFitness > COORDS_NEEDED_OVERALL_AMOUNT) { // Return early if we have a good enough solution return { parallelSegments, arc: overallBest }; } } } } return { parallelSegments, arc: overallBest }; }33:T55c,function* getLineSegments(coords) { const contenders = []; // Identify long line segments function calculateMse(startIndex, endIndex) { const p1 = coords[startIndex]; const p2 = coords[endIndex]; let total = 0; for (let i = startIndex + 1; i < endIndex; i++) { const dist = pointToLineMeters(coords[i], p1, p2); total += sqr(dist); } return total / (endIndex - startIndex + 1); } for (let start = 0; start < coords.length - 1; start++) { let contender = null; for (let end = start + 1; end < coords.length; end++) { const p1 = coords[start]; const p2 = coords[end]; const dist = pointToPointMeters(p1, p2); // Filter only line segments of the right length if (dist < MIN_LINE_SEGMENT) continue; // Filter on how straight the line is const mse = calculateMse(start, end); if (mse > MAX_LINE_MSE) { // Too much error start = end; break; } // Candidate segment if (dist > MAX_LINE_SEGMENT) { // Line segment too long, remove from contention contender = null; // Keep continuing until the line ends continue; } contender = { start, end, p1, p2, dist, mse }; } if (contender != null) { yield contender; } } }34:T72d,function extractParallelSegment(segments, bearings, midpoints, i, j) { // Check for parallel const bearing1 = bearings[i]; const bearing2 = bearings[j]; const angle = angleDifference(bearing1, bearing2); // Check threshold at 0 and 180 degrees if ( (angle > PARALLEL_LINE_ANGLE_THRESHOLD && angle < Math.PI - PARALLEL_LINE_ANGLE_THRESHOLD) || angle > Math.PI + PARALLEL_LINE_ANGLE_THRESHOLD ) { return null; } // Lines are parallel. See if the coords should be swapped and get mid-segment const p1Dist = pointToPointMeters(segments[i].p1, segments[j].p1); const p12Dist = pointToPointMeters(segments[i].p1, segments[j].p2); const shouldSwap = p12Dist < p1Dist; const midP1 = midpoint( segments[i].p1, shouldSwap ? segments[j].p2 : segments[j].p1 ); const midP2 = midpoint( segments[i].p2, shouldSwap ? segments[j].p1 : segments[j].p2 ); // Lines are parallel. Check for angle between midpoints // (should be tangent) const averageBearing = (bearing1 + bearing2) / 2; const midpoint1 = midpoints[i]; const midpoint2 = midpoints[j]; const midpointBearing = bearing(midpoint1, midpoint2); const tangentAngle = angleDifference(midpointBearing, averageBearing); if ( tangentAngle < Math.PI / 2 - TANGENT_LINE_ANGLE_THRESHOLD || tangentAngle > Math.PI / 2 + TANGENT_LINE_ANGLE_THRESHOLD ) { return null; } // Lines midpoints are in the right place. Check for distance // between midpoints const midpointDistance = pointToPointMeters(midpoint1, midpoint2); if ( midpointDistance < MIN_PARALLEL_LINE_DISTANCE || midpointDistance > MAX_PARALLEL_LINE_DISTANCE ) { return null; } // Segments look good! return { segments: [segments[i], segments[j]], mid: [midP1, midP2], radius: midpointDistance / 2 }; }35:T92c,function* arcFitness(parallelSegment, nCoords, coordTree) { const getFitness = (parallelSegment, top, centerOffset) => { // Grab points for the arc const lineBearing = turf.bearing( turf.point(parallelSegment.mid[top ? 1 : 0]), turf.point(parallelSegment.mid[top ? 0 : 1]) ); const center = destinationMeters( parallelSegment.mid[top ? 0 : 1], lineBearing, centerOffset ); const anglePadding = 30; const angleIterations = 5; const searchRadius = 5; const bins = []; for (let i = 0; i < angleIterations; i++) { const angleOffset = -90 + anglePadding + (i / (angleIterations - 1)) * (180 - anglePadding * 2); bins[i] = coordTree.nearest( destinationMeters( center, lineBearing + angleOffset, parallelSegment.radius ), nCoords, searchRadius ).length; } const minBin = Math.min(...bins); return { score: minBin, center }; }; const segmentBearing = bearing(...parallelSegment.mid); // Identify max fitness for top and bottom segments let topBest = null; let bottomBest = null; let topFitness = 0; let bottomFitness = 0; // Iterate top = [true, false] for (let i = 0; i < 2; i++) { const top = i == 0; let maxCenter = top ? parallelSegment.mid[0] : parallelSegment.mid[1]; let maxFitness = 0; // Evaluate optimal set of parameters with arc center offsets for (let j = 0; j < ARC_CENTER_OFFSETS.length; j++) { const centerOffset = ARC_CENTER_OFFSETS[j]; const fitness = getFitness(parallelSegment, top, centerOffset); // Update fitness if new max is set let updated = false; if (top && fitness.score > topFitness) { topBest = { point: fitness.center, radius: parallelSegment.radius, fitness: fitness.score }; topFitness = fitness.score; updated = true; } if (!top && fitness.score > bottomFitness) { bottomBest = { point: fitness.center, radius: parallelSegment.radius, fitness: fitness.score }; bottomFitness = fitness.score; updated = true; } if (updated) yield { topBest, bottomBest, topFitness, bottomFitness }; } } }36:[{"id":"9fca5fe3bbb23eda10f69a1d7272eaa511fe8ac9a6b507722e54a1d46a244d9634d2c9a486bb83592b3e2b62468f7bb2286fedbc9063157bfca840f511f3ec09","href":"https://static.observableusercontent.com/files/9fca5fe3bbb23eda10f69a1d7272eaa511fe8ac9a6b507722e54a1d46a244d9634d2c9a486bb83592b3e2b62468f7bb2286fedbc9063157bfca840f511f3ec09","name":"8x400.fit","type":"application/octet-stream","lastModified":1625116356494.675,"size":196734}] 2f:{"title":"Track Workout Extractor","cells":[{"id":0,"value":"md`# Track Workout Extractor`","pinned":false,"hidden":false,"mode":"ojs"},{"id":143,"value":"{\n const coords = workout.records\n .map(x => [x.position_long, x.position_lat])\n .filter(x => x[0] != null);\n return drawCoords(coords);\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":490,"value":"md`## Params`","pinned":false,"hidden":false,"mode":"ojs"},{"id":145,"value":"// Swap the comments to show a different workout\n\nfile = FileAttachment(\"8x400.fit\")\n// file = FileAttachment(\"400_300_200_100_4x100.fit\")\n// file = FileAttachment(\"10_mile.fit\")\n// file = FileAttachment(\"track_with_cooldown.fit\")\n// file = FileAttachment(\"parkview_track_run.fit\")\n// file = FileAttachment(\"long_track_run.fit\")\n// file = FileAttachment(\"hot_8_200s.fit\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":242,"value":"MIN_LINE_SEGMENT = 65","pinned":false,"hidden":false,"mode":"ojs"},{"id":245,"value":"MAX_LINE_SEGMENT = 130","pinned":false,"hidden":false,"mode":"ojs"},{"id":247,"value":"MAX_LINE_MSE = 4","pinned":false,"hidden":false,"mode":"ojs"},{"id":834,"value":"PARALLEL_LINE_ANGLE_THRESHOLD = Math.PI / 8","pinned":false,"hidden":false,"mode":"ojs"},{"id":836,"value":"TANGENT_LINE_ANGLE_THRESHOLD = Math.PI / 8","pinned":false,"hidden":false,"mode":"ojs"},{"id":840,"value":"MIN_PARALLEL_LINE_DISTANCE = 60","pinned":false,"hidden":false,"mode":"ojs"},{"id":842,"value":"MAX_PARALLEL_LINE_DISTANCE = 100","pinned":false,"hidden":false,"mode":"ojs"},{"id":291,"value":"LINE_CLUSTER_THRESHOLD_ANGLE = Math.PI / 6 // 18 degrees","pinned":false,"hidden":false,"mode":"ojs"},{"id":322,"value":"LINE_CLUSTER_THRESHOLD_DIST = 1","pinned":false,"hidden":false,"mode":"ojs"},{"id":1197,"value":"COORDS_NEEDED_OVERALL_AMOUNT = 5","pinned":false,"hidden":false,"mode":"ojs"},{"id":1292,"value":"ARC_CENTER_OFFSETS = [-30, -25, -20, -15, -10, -5, 0, 5, 10, 15, 20, 25, 30]","pinned":false,"hidden":false,"mode":"ojs"},{"id":984,"value":"ARC_RADIUS_TOLERANCE = 5","pinned":false,"hidden":false,"mode":"ojs"},{"id":643,"value":"md`## Drawing`","pinned":false,"hidden":false,"mode":"ojs"},{"id":108,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":593,"value":"md`## Utility`","pinned":false,"hidden":false,"mode":"ojs"},{"id":215,"value":"function sqr(x) { return x * x }","pinned":false,"hidden":false,"mode":"ojs"},{"id":962,"value":"function getPoint(p) {\n return turf.point([p[0], p[1]]);\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":238,"value":"function pointToPointMeters(p1, p2) {\n const point1 = getPoint(p1);\n const point2 = getPoint(p2);\n return turf.distance(point1, point2, { units: 'kilometers' }) * 1000;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":234,"value":"function pointToLineMeters(p, w, v) {\n // Return point to line distance in meters\n const point = turf.point(p);\n const line = turf.lineString([w, v]);\n return turf.pointToLineDistance(point, line, { units: 'kilometers' }) * 1000;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":868,"value":"function bearing(p1, p2) {\n let bearing = turf.bearing(turf.point(p1), turf.point(p2));\n if (bearing < 0) bearing += 180;\n return (bearing / 180) * Math.PI;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":871,"value":"function angleDifference(a1, a2) {\n return Math.abs(Math.atan2(Math.sin(a1 - a2), Math.cos(a1 - a2)));\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":873,"value":"function midpoint(p1, p2) {\n return turf.getCoord(turf.midpoint(turf.point(p1), turf.point(p2)));\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":1041,"value":"function normalizeBearingDegrees(bearingDegrees) {\n while (bearingDegrees < -180) bearingDegrees += 360;\n while (bearingDegrees > 180) bearingDegrees -= 360;\n return bearingDegrees;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":995,"value":"function destinationMeters(point, bearingDegrees, meters) {\n return turf.getCoord(\n turf.destination(\n turf.point(point),\n meters / 1000,\n normalizeBearingDegrees(bearingDegrees),\n {\n units: 'kilometers'\n }\n )\n );\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":930,"value":"function makeTree(coords) {\n const tree = new kdTree(coords.slice(), pointToPointMeters, [0, 1]);\n return tree;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":599,"value":"md`## Core Algo`","pinned":false,"hidden":false,"mode":"ojs"},{"id":1283,"value":"$32","pinned":true,"hidden":false,"mode":"ojs"},{"id":214,"value":"$33","pinned":true,"hidden":false,"mode":"ojs"},{"id":1279,"value":"function* identifyParallelSegments(coords) {\n // Iterate through each plausible line segment\n const segments = [];\n const bearings = [];\n const midpoints = [];\n for (const segment of getLineSegments(coords)) {\n segments.push(segment);\n bearings.push(bearing(segment.p1, segment.p2));\n midpoints.push(midpoint(segment.p1, segment.p2));\n\n // Check all pairwise combos of segments iteratively\n for (let i = 0; i < segments.length - 1; i++) {\n const parallelSegment = extractParallelSegment(\n segments,\n bearings,\n midpoints,\n i,\n segments.length - 1\n );\n if (parallelSegment != null) yield parallelSegment;\n }\n }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":831,"value":"$34","pinned":true,"hidden":false,"mode":"ojs"},{"id":979,"value":"$35","pinned":true,"hidden":false,"mode":"ojs"},{"id":493,"value":"md`## Scratch pad`","pinned":false,"hidden":false,"mode":"ojs"},{"id":257,"value":"coords = workout.records\n .map(x => [x.position_long, x.position_lat])\n .filter(x => x[0] != null)","pinned":false,"hidden":false,"mode":"ojs"},{"id":860,"value":"segments = Array.from(getLineSegments(coords))","pinned":false,"hidden":false,"mode":"ojs"},{"id":299,"value":"parallelSegments = Array.from(identifyParallelSegments(coords))","pinned":false,"hidden":false,"mode":"ojs"},{"id":1302,"value":"track = identifyTrack(coords)","pinned":false,"hidden":false,"mode":"ojs"},{"id":85,"value":"workout.laps[1]","pinned":true,"hidden":false,"mode":"ojs"},{"id":47,"value":"workout.laps[0].start_time","pinned":true,"hidden":false,"mode":"ojs"},{"id":59,"value":"workoutObj.laps","pinned":true,"hidden":false,"mode":"ojs"},{"id":496,"value":"md`## Render just a lap of workout data`","pinned":false,"hidden":false,"mode":"ojs"},{"id":127,"value":"// pick the lap\nviewof lap = html``","pinned":true,"hidden":false,"mode":"ojs"},{"id":136,"value":"// offset each lap by a number of seconds to align the data better\nviewof factor = html``","pinned":true,"hidden":false,"mode":"ojs"},{"id":78,"value":"{\n const coords = workoutObj.recordsTree\n .search([\n workout.laps[lap].start_time.getTime() + factor * 1000,\n workout.laps[lap].timestamp.getTime() + factor * 1000\n ])\n .map(x => [x.position_long, x.position_lat])\n .filter(x => x[0] != null);\n return drawCoords(coords);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":482,"value":"md`## Workout Wrapper`","pinned":false,"hidden":false,"mode":"ojs"},{"id":57,"value":"workoutObj = new Workout(workout)","pinned":false,"hidden":false,"mode":"ojs"},{"id":53,"value":"class Workout {\n constructor(workout) {\n this.workout = workout;\n\n // Build up a records tree of all events\n this.recordsTree = new IntervalTree();\n for (let i = 0; i < this.workout.records.length; i++) {\n const startTime = this.workout.records[i].timestamp.getTime();\n // End time is either next record, or if at end, last record + 1 second\n const endTime =\n i == this.workout.records.length - 1\n ? this.workout.records[i].timestamp.getTime() + 1000\n : this.workout.records[i + 1].timestamp.getTime();\n this.recordsTree.insert([startTime, endTime], this.workout.records[i]);\n }\n }\n\n get laps() {\n return this.workout.laps;\n }\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":1718,"value":"async function getWorkoutFromFitFile(arrayBuffer) {\n const rawWorkout = await getRawWorkoutFromFitFile(arrayBuffer);\n return new Workout(rawWorkout);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":1726,"value":"function getCoordsFromWorkout(workout) {\n return workout.records\n .map(x => [x.position_long, x.position_lat])\n .filter(x => x[0] != null);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":453,"value":"md`## Fit Parsing`","pinned":false,"hidden":false,"mode":"ojs"},{"id":4,"value":"FitFileParser = (await require('https://bundle.run/fit-file-parser@1.9.0'))\n .default","pinned":false,"hidden":false,"mode":"ojs"},{"id":18,"value":"fitParser = new FitFileParser()","pinned":false,"hidden":false,"mode":"ojs"},{"id":13,"value":"fitContents = (await file).arrayBuffer()","pinned":false,"hidden":false,"mode":"ojs"},{"id":1720,"value":"function getRawWorkoutFromFitFile(arrayBuffer) {\n return new Promise((resolve, reject) => {\n fitParser.parse(arrayBuffer, function(error, data) {\n if (error) {\n reject(error);\n } else {\n resolve(data);\n }\n });\n });\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":22,"value":"workout = await getRawWorkoutFromFitFile(fitContents)","pinned":false,"hidden":false,"mode":"ojs"},{"id":439,"value":"md`## Includes`","pinned":false,"hidden":false,"mode":"ojs"},{"id":148,"value":"convexHull = require('https://bundle.run/convex-hull@1.0.3')","pinned":false,"hidden":false,"mode":"ojs"},{"id":173,"value":"d3 = require('d3-polygon')","pinned":false,"hidden":false,"mode":"ojs"},{"id":196,"value":"turf = require('@turf/turf')","pinned":false,"hidden":false,"mode":"ojs"},{"id":61,"value":"IntervalTree = (await require('@flatten-js/interval-tree')).default","pinned":false,"hidden":false,"mode":"ojs"},{"id":926,"value":"kdTree = (await require('kd-tree-javascript')).kdTree","pinned":false,"hidden":false,"mode":"ojs"},{"id":435,"value":"md`## Units`","pinned":false,"hidden":false,"mode":"ojs"},{"id":38,"value":"MPH_FROM_M_S = 1 / 0.44704","pinned":false,"hidden":false,"mode":"ojs"},{"id":384,"value":"md`## Errata`","pinned":false,"hidden":false,"mode":"ojs"},{"id":33,"value":"workout.laps\n .map(x => {\n return {\n time: x.total_elapsed_time,\n distance: x.total_distance,\n cadence: x.avg_cadence * 2,\n speed: (x.total_distance / x.total_elapsed_time) * MPH_FROM_M_S,\n maxSpeed: x.max_speed * MPH_FROM_M_S\n };\n })\n .filter(x => Math.abs(x.distance - 400) < 40)\n .map(x => x.time)\n .join('\\n')","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W36","stdlib":"1","titling":"auto"}