31:T14b6,map = () => { const wrapper = d3.create("div") .style("position", "relative") .style("width", `${mapwidth}px`) .style("height", `${mapheight}px`); wrapper.append("style").html(css); const canvasStatic = wrapper.append("canvas") .style("position", "absolute"); canvasStatic.node().width = mapwidth; canvasStatic.node().height = mapheight; const contextStatic = canvasStatic.node().getContext("2d"); path.context(contextStatic); // States contextStatic.beginPath(); contextStatic.fillStyle = "#f5f5f5"; contextStatic.strokeStyle = "#767676"; contextStatic.lineWidth = 0.5; statesGeo.features.forEach(path); contextStatic.fill(); contextStatic.stroke(); // Boundaries if (showCurrent) { contextStatic.beginPath(); contextStatic.fillStyle = colors.zoneCurrent; zonesCurrentGeo.features.forEach(path); contextStatic.fill(); } if (showProposed) { contextStatic.beginPath(); contextStatic.fillStyle = colors.zoneProposed; zonesProposedGeo.features.forEach(path); contextStatic.fill(); } const canvas = wrapper.append("canvas") .style("position", "absolute"); canvas.node().width = mapwidth; canvas.node().height = mapheight; const context = canvas.node().getContext("2d"); const svg = wrapper.append("svg") .style("position", "absolute") .attr("width", mapwidth) .attr("height", mapheight); svg.selectAll(".state-label") .data(statesData) .join("text") .attr("class", "state-label") .attr("transform", d => `translate(${projection([d.lon, d.lat])})`) .text(d => d.name_abbr); // whale const whale = svg.append("g") .attr("class", "whale") .html(whaleString); const tag = svg.append("circle") .attr("fill", "#ffb371") .attr("r", 2); const scaleBar = svg.append("g") .attr("class", "scale-bar") .call(scaleBarGenerator); scaleBar.select(".label") .text(`${scaleBar.select(".tick:last-of-type text").text()} miles`); return Object.assign(wrapper.node(), { update(t) { const coordinates = bishopInterpolator(t); const projected = projection(coordinates); context.clearRect(0, 0, mapwidth, mapheight); path.context(context); // Ships // context.fillStyle = colors.vesselFaster; segGrouped.forEach(ship => { const curr = ship.position_interpolator(t); const prev = ship.position_interpolator(t - interval); if (curr) { context.beginPath(); const [ x, y ] = projection(curr); if (prev) { const knots = radiansToNauticalMiles(d3.geoDistance(curr, prev)) * 3; // interval is every 20 minutes, knots is per hour context.fillStyle = knots > 12 ? colors.vesselFaster : colors.vesselSlower; const angle = geometric.lineAngle([[x, y], projection(prev)]); const length = knots / 10; context.moveTo(...geometric.pointTranslate([x, y], angle - 90, shipRadius)); context.lineTo(...geometric.pointTranslate([x, y], angle + 90, shipRadius)); context.lineTo(...geometric.pointTranslate([x, y], angle, length)); context.closePath(); context.fill() } else { context.fillStyle = colors.vesselSlower; } context.arc(x, y, shipRadius, 0, Math.PI * 2); context.fill(); } }); // Journey context.beginPath(); context.lineWidth = 1; context.strokeStyle = "#202020"; const filtered = bishopGeo.features .filter(leg => leg.properties.end.datetime.getTime() <= t); if (filtered.length) { // connect to whale const journeyLast = filtered[filtered.length - 1]; if (journeyLast) { const start = journeyLast.properties.end; filtered.push({ type: "Feature", geometry: { type: "LineString", coordinates: [ [start.lon, start.lat], coordinates ] } }); } filtered.forEach(path); context.stroke(); } path.context(null); const whaleAngle = (() => { if (t === bishopStart.getTime()){ const positionsNext = [0.1, 0.5, 1, 1.5, 2].map(n => { const c = bishopInterpolator(t + interval * n); return c[0] ? projection(c) : projected; }); return d3.mean(positionsNext, d => geometric.lineAngle([d, projected])); } else { const positionsPrev = [0.1, 0.5, 1, 1.5, 2].map(n => { const c = bishopInterpolator(t - interval * n); return c[0] ? projection(c) : projected; }); return d3.mean(positionsPrev, d => geometric.lineAngle([projected, d])); } })(); whale .attr("transform", `translate(${[projected[0] - whaleWidth * 0.5, projected[1] - whaleHeight * 0.5]}) rotate(${whaleAngle - 90}, ${whaleWidth * 0.5}, ${whaleHeight * 0.5})`); tag .attr("cx", d => projected[0]) .attr("cy", d => projected[1]); } }); }32:T1104,whaleString = ` `33:T50b,statesData = [ { name: "Connecticut", name_abbr: "Conn.", name_postal: "CT", lon: -72.649234, lat: 41.5 }, { name: "Delaware", name_abbr: "Del.", name_postal: "DE", lon: -75.441883, lat: 38.803258 }, { name: "Florida", name_abbr: "Fla.", name_postal: "FL", lon: -82.277997, lat: 29.639664, }, { name: "Georgia", name_abbr: "Ga.", name_postal: "GA", lon: -83.376207, lat: 32.613036, }, { name: "Maryland", name_abbr: "Md.", name_postal: "MD", lon: -77.023139, lat: 39.3 }, { name: "Massachusetts", name_abbr: "Mass.", name_postal: "MA", lon: -72.1, lat: 42.2, }, { name: "New Jersey", name_abbr: "N.J.", name_postal: "NJ", lon: -74.64, lat: 39.691160 }, { name: "North Carolina", name_abbr: "N.C.", name_postal: "NC", lon: -79.049846, lat: 35.5 }, { name: "Rhode Island", name_abbr: "R.I.", name_postal: "RI", lon: -71.566889, lat: 41.55 }, { name: "South Carolina", name_abbr: "S.C.", name_postal: "SC", lon: -80.764230, lat: 33.9, }, { name: "Virginia", name_abbr: "Va.", name_postal: "VA", lon: -78.768774, lat: 37.259825 } ]34:T78d,// Group the data by segments and filter out segments that are too short segGrouped = { const data = d3.groups(shipData, d => d.seg_id) .map(([seg_id, entries]) => { const [lon_min, lon_max] = d3.extent(entries, d => d.lon) const [lat_min, lat_max] = d3.extent(entries, d => d.lat) const [ms_min, ms_max] = d3.extent(entries, d => d.datetime.getTime()) let closest_distance = Infinity; const bishopInRange = bishopData.filter(d => d.datetime.getTime() >= ms_min && d.datetime.getTime() <= ms_max) const bishopTree = new BishopBush() bishopTree.load(bishopInRange); const entriesInRange = entries .map(d => { const bishops = bishopTree.search({ minX: d.lon - minBishopDist, minY: d.lat - minBishopDist, maxX: d.lon + minBishopDist, maxY: d.lat + minBishopDist }); if (bishops.length) { return bishops.map(d0 => { const ms = Math.abs(d0.datetime.getTime() - d.datetime.getTime()); return { hours: ms / (1000 * 60 * 60), miles: 3959 * d3.geoDistance([d0.lon, d0.lat], [d.lon, d.lat]) } }) } else { return null; } }) .filter(d => d) .flat() .filter(d0 => d0.hours <= minHours) return { seg_id, entries, avg_knots: d3.mean(entries, d => d.speed_knots), max_knots: d3.max(entries, d => d.speed_knots), length: geometric.polygonLength(entries.map(d => [d.lon, d.lat])), ms_min, ms_max, entriesInRange, position_interpolator: pathInterpolate(entries) } }) .sort((a, b) => d3.descending(a.length, b.length)) if (showAllShips) { return data; } else { return data .filter(d => d.entriesInRange.length > 0) } }35:[{"id":"cf34c555db241dbb46106f381c456127b1507c347c714fe8a04980dd7682bb84189ce46838dbc90272c99e71464b369b485cd633d7776f511bef0c907070c7b0","href":"https://static.observableusercontent.com/files/cf34c555db241dbb46106f381c456127b1507c347c714fe8a04980dd7682bb84189ce46838dbc90272c99e71464b369b485cd633d7776f511bef0c907070c7b0","name":"20240429_harry_stevens.csv (1).zip","type":"application/zip","lastModified":1714698459671.051,"size":39812016},{"id":"097b29259d40f3d103dd976d41932b66b2b766d9b3ddd83069367d5ddf168386c99fa1930c94c30190c9344e2499f3c0cc6a42cab4e2d04302d723d2af7b112b","href":"https://static.observableusercontent.com/files/097b29259d40f3d103dd976d41932b66b2b766d9b3ddd83069367d5ddf168386c99fa1930c94c30190c9344e2499f3c0cc6a42cab4e2d04302d723d2af7b112b","name":"NARW filtered Argos tracks_calving seasons 2015 and 2016_Movebank DAR output_27NOV2020.csv","type":"text/csv","lastModified":1714698459671.051,"size":120587},{"id":"dd02d7c41c4cbe16111c34de3017ddaa603154ae5a395c27f8f620fb760fcbb2597255c2866fde9a9af73c4e801376394c22ce18b6da1f7cd38064d58f527d44","href":"https://static.observableusercontent.com/files/dd02d7c41c4cbe16111c34de3017ddaa603154ae5a395c27f8f620fb760fcbb2597255c2866fde9a9af73c4e801376394c22ce18b6da1f7cd38064d58f527d44","name":"North_Atlantic_Right_Whale_Seasonal_Management_Areas.zip","type":"application/zip","lastModified":1714698459671.051,"size":1338840},{"id":"9c1cd509951f1ff85a80d4c50809ded4feb746674666ed4c351bc59b0394a355f55c148fd2edb234df20dabab44d18a7e1b0bc85c53d695a1822968519639fd4","href":"https://static.observableusercontent.com/files/9c1cd509951f1ff85a80d4c50809ded4feb746674666ed4c351bc59b0394a355f55c148fd2edb234df20dabab44d18a7e1b0bc85c53d695a1822968519639fd4","name":"Proposed-Right-Whale-Seasonal-Speed-Zones.zip","type":"application/zip","lastModified":1714698459671.051,"size":2534594},{"id":"ab1462487956729172d82edff0e1c770bc55e04c5419f355ec2e45a66d277d3eb269a70319e4f8aab01d480032deee8cc9a22182d6bc109cf7a91a6cafe261fb","href":"https://static.observableusercontent.com/files/ab1462487956729172d82edff0e1c770bc55e04c5419f355ec2e45a66d277d3eb269a70319e4f8aab01d480032deee8cc9a22182d6bc109cf7a91a6cafe261fb","name":"states.topo.json","type":"application/json","lastModified":1715088160678.285,"size":67221}] 2f:{"title":"Animation of Bishop the right whale’s northward migration","cells":[{"id":0,"value":"# Animation of Bishop the right whale’s northward migration","pinned":false,"hidden":false,"mode":"md"},{"id":1291,"value":"This notebook contains the data and code to produce a simpler version of the animated map seen in [“Bishop vanished. His species can still be saved.”](https://www.washingtonpost.com/climate-environment/interactive/2024/north-atlantic-right-whale-species-challenges/), published in The Washington Post on May 11, 2024.","pinned":false,"hidden":false,"mode":"md"},{"id":1123,"value":"On Jan. 20, 2015, off the coast of New Smyrna Beach, Fla., scientists tagged Bishop, a 1-year-old North Atlantic right whale, with a satellite transmitter. For the next 50 days, he broadcast his location as he migrated over 1,000 miles up the East Coast. It was one of the longest transmissions of his species ever recorded.","pinned":false,"hidden":false,"mode":"md"},{"id":1352,"value":"On the map below, the dots show the positions of vessels that had their AIS transponders turned on. Pink vessels are moving faster than 10 knots. I filtered out vessels that did not come close to Bishop, but there is a toggle below to show all vessels.","pinned":false,"hidden":false,"mode":"md"},{"id":115,"value":"viewof time = Scrubber(\n d3.range(bishopStart.getTime(), bishopEnd.getTime(), interval),\n {\n autoplay: false,\n loop: false,\n format: date => new Date(date).toLocaleString(\"en\", {\n dateStyle: \"long\",\n timeStyle: \"short\"\n })\n }\n)","pinned":false,"hidden":false,"mode":"ojs"},{"id":1437,"value":"display = map()","pinned":false,"hidden":false,"mode":"ojs"},{"id":1117,"value":"viewof showCurrent = Inputs.toggle({ label: \"Show current speed limit zones:\" })","pinned":false,"hidden":false,"mode":"ojs"},{"id":1113,"value":"viewof showProposed = Inputs.toggle({ label: \"Show proposed speed limit zones:\" })","pinned":false,"hidden":false,"mode":"ojs"},{"id":1367,"value":"viewof showAllShips = Inputs.toggle({ label: \"Show all ships:\", value: false })","pinned":false,"hidden":false,"mode":"ojs"},{"id":1125,"value":"On his migration north, Bishop passed hundreds of speeding vessels, including fishing boats, transport ships, and leisure craft. He made it to the north, but this year alone, three right whales have been found dead with injuries consistent with boat impacts. Bishop himself has not been since 2017 and is presumed dead. North Atlantic right whales are critically endangered, with just 350 left in the wild.","pinned":false,"hidden":false,"mode":"md"},{"id":1129,"value":"The Biden administration has proposed expanding the speed-limited area and applying speed limits to vessels smaller than 65 feet. Scientists say it would help save North Atlantic right whales from extinction, but industry groups worry it would raise costs.","pinned":false,"hidden":false,"mode":"md"},{"id":1288,"value":"NOAA Fisheries provided Bishop’s location data as well as the boundaries of the [current](https://www.fisheries.noaa.gov/resource/map/north-atlantic-right-whale-seasonal-management-areas-sma) and [proposed](https://www.fisheries.noaa.gov/resource/data/proposed-right-whale-seasonal-speed-zones) speed-limited areas. The vessels’ location data was processed and provided by [Global Fishing Watch](https://globalfishingwatch.org/).","pinned":false,"hidden":false,"mode":"md"},{"id":1186,"value":"toc({ selector: \"h2,h3,h4\", heading: \"Jump to:\" })","pinned":false,"hidden":false,"mode":"ojs"},{"id":1281,"value":"## Graphics","pinned":false,"hidden":false,"mode":"md"},{"id":75,"value":"$31","pinned":true,"hidden":false,"mode":"ojs"},{"id":1328,"value":"display.update(time)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1238,"value":"## Style","pinned":false,"hidden":false,"mode":"md"},{"id":1262,"value":"css = `\n.whale {\n stroke-width: 0.5px;\n}\n.whale .whale-black {\n fill: #666;\n stroke: #666;\n \n}\n.whale .whale-white {\n fill: white;\n stroke: #666;\n}\n.whale .whale-none {\n fill: none;\n stroke: none;\n}\n.scale-bar text {\n font-family: ${franklinLight};\n font-size: 14px;\n}\n.scale-bar .tick {\n opacity: 0;\n pointer-events: none;\n}\n.state-label {\n font-family: ${franklinLight};\n font-size: 14px;\n fill: #767676;\n letter-spacing: 1.5px;\n paint-order: stroke fill;\n stroke: #f5f5f5;\n stroke-linejoin: round;\n stroke-opacity: 0.6;\n stroke-width: 4px;\n text-anchor: middle;\n text-transform: uppercase;\n}\n`","pinned":true,"hidden":false,"mode":"ojs"},{"id":1266,"value":"whaleWidth = 11.999999046325684","pinned":true,"hidden":false,"mode":"ojs"},{"id":1268,"value":"whaleHeight = 24.84000015258789","pinned":true,"hidden":false,"mode":"ojs"},{"id":1241,"value":"colors = ({\n \"vesselSlower\": \"#000000\",\n \"vesselFaster\": \"#ff4f83\",\n \"zoneCurrent\": \"#d3e7fa\",\n \"zoneProposed\": \"#5784c5\"\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":350,"value":"shipRadius = 2","pinned":true,"hidden":false,"mode":"ojs"},{"id":1257,"value":"$32","pinned":true,"hidden":false,"mode":"ojs"},{"id":65,"value":"## Projection","pinned":false,"hidden":false,"mode":"md"},{"id":69,"value":"projection = d3.geoMercator()\n .fitExtent([[pad, pad], [mapwidth - pad, mapheight - pad]], boundsGeo);","pinned":true,"hidden":false,"mode":"ojs"},{"id":72,"value":"path = d3.geoPath(projection)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1388,"value":"scaleBarGenerator = d3.geoScaleBar()\n .projection(projection)\n .size([mapwidth, mapheight])\n .left((16 / mapwidth))\n .top(1 - (24 / mapheight))\n .units(d3.geoScaleMiles)\n .tickSize(null)","pinned":true,"hidden":false,"mode":"ojs"},{"id":52,"value":"## Dimensions","pinned":false,"hidden":false,"mode":"md"},{"id":54,"value":"mapwidth = Math.min(640, width)","pinned":true,"hidden":false,"mode":"ojs"},{"id":59,"value":"mapheight = mapwidth * aspect","pinned":true,"hidden":false,"mode":"ojs"},{"id":56,"value":"aspect = 1.4","pinned":true,"hidden":false,"mode":"ojs"},{"id":1480,"value":"pad = 50","pinned":true,"hidden":false,"mode":"ojs"},{"id":30,"value":"## Data","pinned":false,"hidden":false,"mode":"md"},{"id":1192,"value":"### Input","pinned":false,"hidden":false,"mode":"md"},{"id":572,"value":"// Tagged right whale location data from NOAA Fisheries\nwhaleData = FileAttachment(\"NARW filtered Argos tracks_calving seasons 2015 and 2016_Movebank DAR output_27NOV2020.csv\").csv()","pinned":true,"hidden":false,"mode":"ojs"},{"id":724,"value":"// Filtered from Natural Earth 50m cultural vectors: https://www.naturalearthdata.com/downloads/50m-cultural-vectors/\nstatesTopo = FileAttachment(\"states.topo.json\").json()","pinned":true,"hidden":false,"mode":"ojs"},{"id":730,"value":"// AIS data from Tyler Clavelle at Global Fishing Watch, which also processed the data\nshipZip = FileAttachment(\"20240429_harry_stevens.csv (1).zip\").zip()","pinned":true,"hidden":false,"mode":"ojs"},{"id":627,"value":"// https://www.fisheries.noaa.gov/resource/data/proposed-right-whale-seasonal-speed-zones\nzonesProposedGeo = shpToGeo(await FileAttachment(\"Proposed-Right-Whale-Seasonal-Speed-Zones.zip\").zip())","pinned":true,"hidden":false,"mode":"ojs"},{"id":1107,"value":"// From Eric M. Patterson, Ph.D., of NOAA Fisheries\n// You can also log in and download from here: https://www.fisheries.noaa.gov/resource/map/north-atlantic-right-whale-seasonal-management-areas-sma\nzonesCurrentGeo = shpToGeo(await FileAttachment(\"North_Atlantic_Right_Whale_Seasonal_Management_Areas.zip\").zip())","pinned":true,"hidden":false,"mode":"ojs"},{"id":1199,"value":"### Analysis","pinned":false,"hidden":false,"mode":"md"},{"id":295,"value":"interval = 60e3 * 20","pinned":true,"hidden":false,"mode":"ojs"},{"id":1201,"value":"#### Bishop","pinned":false,"hidden":false,"mode":"md"},{"id":574,"value":"bishopData = whaleData\n .filter(d => d.WhaleID === \"Eg4445\")\n .map((d, i) => {\n return {\n // frame: i,\n lon: +d[\"location-long\"],\n lat: +d[\"location-lat\"],\n datetime: new Date(`${d.timestamp.replace(\" \", \"T\")}Z`)\n }\n })","pinned":true,"hidden":false,"mode":"ojs"},{"id":36,"value":"bishopStart = d3.min(bishopData, d => d.datetime)","pinned":true,"hidden":false,"mode":"ojs"},{"id":50,"value":"bishopEnd = d3.max(bishopData, d => d.datetime)","pinned":true,"hidden":false,"mode":"ojs"},{"id":604,"value":"bishopRange = bishopEnd.getTime() - bishopStart.getTime()","pinned":true,"hidden":false,"mode":"ojs"},{"id":183,"value":"bishopInterpolator = pathInterpolate(bishopData, bishopStart.getTime(), bishopEnd.getTime())","pinned":true,"hidden":false,"mode":"ojs"},{"id":27,"value":"bishopGeo = ({\n type: \"FeatureCollection\",\n features: bishopData\n .map((start, i) => {\n if (i === bishopData.length - 1) return;\n \n const end = bishopData[i + 1];\n return {\n type: \"Feature\",\n properties: {\n start,\n end\n },\n geometry: {\n type: \"LineString\",\n coordinates: [\n [start.lon, start.lat],\n [end.lon, end.lat]\n ]\n }\n }\n })\n .filter(d => d)\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":1205,"value":"#### States","pinned":false,"hidden":false,"mode":"md"},{"id":221,"value":"statesGeo = topojson.feature(statesTopo, statesTopo.objects.states)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1338,"value":"$33","pinned":true,"hidden":false,"mode":"ojs"},{"id":1211,"value":"#### Ships","pinned":false,"hidden":false,"mode":"md"},{"id":255,"value":"shipDataNums = [\"lat\", \"lon\", \"speed_knots\", \"best_length_m\"]","pinned":true,"hidden":false,"mode":"ojs"},{"id":253,"value":"shipData = (await shipZip.file(\"20240429_harry_stevens.csv\").csv())\n .map(d => {\n shipDataNums.forEach(c => {\n d[c] = +d[c];\n d.datetime = new Date(d.timestamp);\n });\n return d;\n })","pinned":true,"hidden":false,"mode":"ojs"},{"id":534,"value":"avgKnots = 2 // filter out slowest segments","pinned":true,"hidden":false,"mode":"ojs"},{"id":555,"value":"length = 5 // filter out short segments","pinned":true,"hidden":false,"mode":"ojs"},{"id":858,"value":"minHours = 24 // filter for ships that were close in a certain time period","pinned":true,"hidden":false,"mode":"ojs"},{"id":878,"value":"minMiles = 10 // filter for ships that were close to bishop","pinned":true,"hidden":false,"mode":"ojs"},{"id":841,"value":"minBishopDist = minMiles / (54.6 * 2) // degrees longitude","pinned":true,"hidden":false,"mode":"ojs"},{"id":261,"value":"$34","pinned":true,"hidden":false,"mode":"ojs"},{"id":768,"value":"// An RBush to index Bishop's position data\nclass BishopBush extends RBush {\n toBBox(d) { return {minX: d.lon, minY: d.lat, maxX: d.lon, maxY: d.lat}; }\n compareMinX(a, b) { return a.lon - b.lon; }\n compareMinY(a, b) { return a.lat - b.lat; }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":1513,"value":"#### Zones","pinned":false,"hidden":false,"mode":"md"},{"id":1515,"value":"bounds = d3.geoBounds(zonesProposedGeo);","pinned":true,"hidden":false,"mode":"ojs"},{"id":1460,"value":"boundsGeo = ({\n type: \"Polygon\",\n coordinates: [[\n bounds[0],\n [bounds[0][0], bounds[1][1]],\n bounds[1],\n [bounds[1][0], bounds[0][1]],\n bounds[0]\n ]]\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":215,"value":"## Utilities","pinned":false,"hidden":false,"mode":"md"},{"id":1011,"value":"function radiansToNauticalMiles(radians) {\n const earthRadiusKm = 6371; // Earth's average radius in kilometers\n const nauticalMileInMeters = 1852; // One nautical mile in meters\n const nauticalMilesPerRadian = 2 * Math.PI * earthRadiusKm * 1000 / nauticalMileInMeters;\n return radians * nauticalMilesPerRadian;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":926,"value":"function createInterpolator(accessor, interpolator){\n return (path) => {\n const [minTime, maxTime] = d3.extent(path, d => d.datetime.getTime());\n \n return (time) => {\n if (time < minTime) {\n return null;\n }\n \n if (time > maxTime) {\n return null;\n }\n \n // Find the segment\n let segmentStart, segmentEnd, segmentT;\n for (let i = 0, l = path.length - 1; i < l; i++) {\n const start = path[i], end = path[i + 1];\n const startTime = start.datetime.getTime();\n const endTime = end.datetime.getTime();\n \n if (time >= startTime && time <= endTime) {\n segmentStart = accessor(start);\n segmentEnd = accessor(end);\n segmentT = (time - startTime) / (endTime - startTime);\n break;\n }\n }\n \n if (!segmentStart || !segmentEnd) {\n return null;\n }\n \n return interpolator(segmentStart, segmentEnd)(segmentT); \n }\n }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":117,"value":"pathInterpolate = createInterpolator(\n d => [d.lon, d.lat],\n (a, b) => geometric.lineInterpolate([a, b])\n)","pinned":true,"hidden":false,"mode":"ojs"},{"id":107,"value":"## Imports","pinned":false,"hidden":false,"mode":"md"},{"id":1345,"value":"import { franklinLight } from \"@climatelab/fonts@46\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":109,"value":"import {Scrubber} from \"@mbostock/scrubber@255\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":649,"value":"import { shpToGeo } from \"@climatelab/shapefile-to-geojson@16\";","pinned":true,"hidden":false,"mode":"ojs"},{"id":1172,"value":"import { toc } from \"@climatelab/toc@45\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":1390,"value":"d3 = require(\"d3@7\", \"d3-geo-scale-bar@1\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":123,"value":"geometric = require(\"geometric@2\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":770,"value":"RBush = require(\"rbush@3\");","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W35","stdlib":"1","titling":"auto"}