30:T6a8,function asteroidDataPlot(mode,scale) { let modeOptions = modes[mode]; let data = objectHistory; function x(d) { return new Date(d.fetched); } function y(d) { return {ip: ip, palermo: palermo, numObservations: numObservations, daysObserved:daysObserved}[mode](d); } function ip(d) { let nextImpact = getNextImpactData(d); return Number(nextImpact.ip); } function palermo(d) { let nextImpact = getNextImpactData(d); return Number(nextImpact.ps); } function torino(d) { let nextImpact = getNextImpactData(d); return Number(nextImpact.ts); } function daysObserved(d) { return Number(d.summary.darc.split(" ")[0]); } function numObservations(d) { return Number(d.summary.nobs); } function mass(d) { return Number(d.summary.mass); } function energy(d) { return Number(d.summary.energy); } function fill(d) { //return torino(d); return daysObserved(d); } let title = "Asteroid 2024 YR4 " + modeOptions.title; let subtitle = modeOptions.subtitle; let label = modeOptions.label; //return data.map(y); return Plot.plot({ title, subtitle, caption: html`https://observablehq.com/@labvegas/asteroid-2032
Data from https://ssd-api.jpl.nasa.gov/doc/sentry.html`, marginLeft: 55, marginRight: 55, width, x: { grid: true, label: "Report date" }, y: { label, grid: true, percent: modeOptions.percent, zero: toggleZero && scale != "log", type: scale, }, marks: [ Plot.dot(data, {x, y, fill, tip:true}), Plot.line(data, {x, y, stroke:fill, tip:true}), Plot.line(data, {x, y, stroke:"#3333"}), ] }); }31:T474,async function checkForChanges(){ if (!objectDetails || objectDetailsJSON === "null") { return {}; } let newObjectDetails = await getObjectDetails(config.objDes); let d = canonicalizeDetails(newObjectDetails) ; delete d.fetched; let newObjectDetailsJSON = JSON.stringify(d); let changed = newObjectDetailsJSON !== objectDetailsJSON; if (changed) { let oldObjectDetails = objectDetails; mutable objectDetails = newObjectDetails; let newObjectDetails2 = getObjectDetails(config.objDes, true); let d = canonicalizeDetails(newObjectDetails2) ; delete d.fetched; let newObjectDetails2JSON = JSON.stringify(d); let changed2 = newObjectDetailsJSON !== newObjectDetails2JSON; let changedBack = objectDetailsJSON == newObjectDetails2JSON; console.log("new objectDetails",{changed, changed2, changedBack, oldObjectDetails, newObjectDetails, newObjectDetails2}); if (changed2) { mutable objectDetails = newObjectDetails2; return {changed, ...newObjectDetails2}; } } else { console.log("objectDetails unchanged"); } return {changed, ...newObjectDetails}; }32:Tf3e,oldData = d3.sort([ { fetched: 1736105294000, url: "https://web.archive.org/web/20250105112814/https://ssd-api.jpl.nasa.gov/sentry.api?des=2024%20YR4&www=1", "summary": { "h": "23.86", "fullname": "(2024 YR4)", "nsat": "0", "first_obs": "2024-12-26", "mass": "2.52e+08", "ps_max": "-1.61", "v_inf": "13.26", "energy": "9.019e+00", "last_obs": "2025-01-04", "ndop": 0, "ndel": 0, "method": "IOBS", "nobs": 137, "n_imp": 8, "cdate": "2025-01-04 11:30:30", "des": "2024 YR4", "ps_cum": "-1.48", "diameter": "0.057", "darc": "8.9206 days", "pdate": "2025-01-04 23:55:08", "v_imp": "17.32", "ip": "0.001359994838", "ts_max": "1" }, "signature": { "version": "2.0", "source": "NASA/JPL Sentry Data API" }, "data": [ { "ts": "0", "ps": "-6.64", "sigma_vi": "0.7151", "energy": "8.775e+00", "ip": "2.796e-08", "date": "2047-12-22.05" }, { "ts": "0", "sigma_vi": "0.6821", "ps": "-5.95", "ip": "8.765e-08", "date": "2039-12-23.35", "energy": "9.022e+00" }, { "ts": "0", "ps": "-7.47", "sigma_vi": "0.7318", "energy": "8.993e+00", "date": "2043-12-23.18", "ip": "3.302e-09" }, { "sigma_vi": "0.6830", "ps": "-8.07", "energy": "8.889e+00", "ip": "2.457e-09", "date": "2079-12-22.73", "ts": "0" }, { "ts": "0", "energy": "8.791e+00", "date": "2047-12-22.07", "ip": "7.569e-09", "sigma_vi": "0.7463", "ps": "-7.20" }, { "ip": "1.659e-07", "date": "2047-12-22.05", "energy": "8.778e+00", "ps": "-5.86", "sigma_vi": "0.6998", "ts": "0" }, { "energy": "9.036e+00", "date": "2032-12-22.62", "ip": "3.377e-04", "ps": "-2.09", "sigma_vi": "0.7295", "ts": "0" }, { "ts": "1", "energy": "9.014e+00", "ip": "1.022e-03", "date": "2032-12-22.59", "sigma_vi": "0.6629", "ps": "-1.61" } ] }, {fetched: 1737566113000, url:"https://web.archive.org/web/20250122091513/https://ssd-api.jpl.nasa.gov/sentry.api?des=2024%20YR4&www=1","signature":{"version":"2.0","source":"NASA/JPL Sentry Data API"},"data":[{"ts":"0","ip":"3.410e-09","ps":"-7.84","energy":"8.282e+00","sigma_vi":"0.0713","date":"2067-06-22.73"},{"ts":"0","ip":"2.806e-09","ps":"-7.97","energy":"8.296e+00","sigma_vi":"3.0660","date":"2071-06-22.72"},{"ts":"0","ip":"1.464e-07","ps":"-5.95","energy":"8.088e+00","sigma_vi":"0.1432","date":"2047-12-22.05"},{"ts":"0","ip":"8.672e-07","energy":"8.091e+00","ps":"-5.17","sigma_vi":"0.0810","date":"2047-12-22.05"},{"ip":"4.567e-07","ps":"-5.26","energy":"8.315e+00","ts":"0","date":"2039-12-23.35","sigma_vi":"0.0164"},{"ip":"5.213e-03","ps":"-0.93","energy":"8.308e+00","ts":"1","date":"2032-12-22.59","sigma_vi":"0.0702"}],"summary":{"cdate":"2025-01-21 07:27:44","mass":"2.33e+08","h":"23.92","n_imp":6,"nsat":"0","ndel":0,"v_imp":"17.32","ndop":0,"first_obs":"2024-12-25","v_inf":"13.26","ps_cum":"-0.93","method":"IOBS","ts_max":"1","des":"2024 YR4","diameter":"0.056","fullname":"(2024 YR4)","pdate":"2025-01-21 15:50:50","nobs":206,"darc":"26.836 days","last_obs":"2025-01-21","ps_max":"-0.93","ip":"0.005214476516","energy":"8.308e+00"}} ], d=>-d.fetched)33:T493,{ let xmin = -3; let xmax = 3; let dx = 0.001; let x0 = xRange; let r = radiusOfImpact; let sigma = sigmaRange; let mean = 0; let cum = 0 ; let data = d3.range(xmin,xmax,dx).map(x=>{ let p = normDist(x,mean,sigma) ; cum += p * dx; return { x, cum, p, }; }); data.forEach((d,i,a)=>{ let id = Math.floor(r/dx); let cum0 = 0; if (i >= id) { cum0 = a[i-id].cum; } let cum1 = 1; if (i + id < a.length) { cum1 = a[i+id].cum; d.prob = cum1 - cum0; } }); function y (d) { return d.prob; } //return data; let d0 = data.find(d=>Math.abs(d.x-x0) < dx/2 ) return Plot.plot({ title: "Probability", marginLeft: 55, marginRight: 55, width, x: { grid: true, label: "Position" }, y: { label: "Probability (%)", grid: true, percent: true, }, marks: [ Plot.line(data, {x:"x", y, tip:true}), Plot.dot([d0], {x:"x", y, tip:true}), Plot.text([d0], {x:"x", y, text:d=>"" + Math.round(d.prob*100*1000)/1000 + "%", textAnchor:"end", lineAnchor:"bottom", dx:-5, dy:-5}), ] }); }34:T479,{ return "disabled"; let data = randData ; let days = daysRange; let regData = data.slice(0,days); let dataLM = new ML.SimpleLinearRegression(regData.map(x), regData.map(y)); console.log(dataLM); let dataCorr = dataLM.score(regData.map(x), regData.map(y)); console.log(dataCorr); regData.push({ x: daysUntilImpact, y: dataLM.intercept + dataLM.slope * daysUntilImpact }); let regLine = [ {x: 0, y:dataLM.intercept}, {x: daysUntilImpact, y:dataLM.intercept + dataLM.slope * daysUntilImpact}, ] //return data; data.forEach((d,i,a)=>{ }); function y(d) { return d.y; } function x(d) { return d.x; } //return data; return Plot.plot({ title: "Position at day", marginLeft: 55, marginRight: 55, width, x: { grid: true, label: "Day" }, y: { label: "Observed position offset from actual", grid: true, percent: false, }, marks: [ Plot.dot(data, {x, y, opacity: d=>d.x < days ? 1: 0.1 , tip:true}), Plot.linearRegressionY(data.slice(0,days), {x, y}), Plot.line(regLine, {x, y, tip:false}), ] }); }35:[] 2e:{"title":"Asteroid 2024 YR4","cells":[{"id":0,"value":"# Asteroid 2024 YR4","pinned":false,"hidden":false,"mode":"md"},{"id":26,"value":"### Current probability that Asteroid 2024 YR4 is on course to impact Earth on ${impactDate.toUTCString().slice(5,16)} (based on ${objectDetails.summary.darc} days of observation): \n# ${Math.round(Number(nextImpactData.ip)*10000000000)/100000000}%\n### Or 1 in ${(Math.round(1/Number(nextImpactData.ip))).toLocaleString()}","pinned":false,"hidden":false,"mode":"md"},{"id":671,"value":"Torino scale: ${nextImpactData.ts}","pinned":false,"hidden":false,"mode":"md"},{"id":694,"value":"### NASA: Latest Calculations Conclude Asteroid 2024 YR4 Now Poses No Significant Threat to Earth in 2032 and Beyond\n\nhttps://blogs.nasa.gov/planetarydefense/2025/02/24/latest-calculations-conclude-asteroid-2024-yr4-now-poses-no-significant-threat-to-earth-in-2032-and-beyond/","pinned":false,"hidden":false,"mode":"md"},{"id":659,"value":"https://cneos.jpl.nasa.gov/sentry/details.html#?des=2024%20YR4","pinned":false,"hidden":false,"mode":"md"},{"id":21,"value":"Asteroid ${objectDetails.summary.des} was last observed ${objectDetails.summary.last_obs}","pinned":false,"hidden":false,"mode":"md"},{"id":642,"value":"asteroidDataPlot(modeSelect, toggleLog ? \"log\":undefined)","pinned":false,"hidden":false,"mode":"ojs"},{"id":701,"value":"viewof toggleLog = Inputs.toggle({label: \"Log scale\", value: false})","pinned":false,"hidden":false,"mode":"ojs"},{"id":317,"value":"viewof toggleZero = Inputs.toggle({label: \"Include zero\", value: true})","pinned":false,"hidden":false,"mode":"ojs"},{"id":442,"value":"viewof modeSelect = Inputs.select(Object.keys(modes), {label: \"Select mode\", format: x => modes[x].title})","pinned":false,"hidden":false,"mode":"ojs"},{"id":646,"value":"asteroidDataPlot(\"daysObserved\")","pinned":false,"hidden":false,"mode":"ojs"},{"id":649,"value":"asteroidDataPlot(\"numObservations\")","pinned":false,"hidden":false,"mode":"ojs"},{"id":651,"value":"asteroidDataPlot(\"palermo\")","pinned":false,"hidden":false,"mode":"ojs"},{"id":120,"value":"NASA's image showing the uncertainty region on Dec 22, 2025: \n

The yellow dots show the position uncertainty of asteroid 2024 YR4 when it encounters Earth in 2032, based on observations up to January 31, 2025 (orbit solution 40). Only 1.6% of this region intersects the Earth, which is the small dot at the center of the Moon's orbit.

","pinned":false,"hidden":false,"mode":"html"},{"id":187,"value":"Risk corridor map
\n\n $\"Impact$ ","pinned":false,"hidden":false,"mode":"html"},{"id":396,"value":"Orbit viewer: https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2024%20YR4&view=VOP","pinned":false,"hidden":false,"mode":"md"},{"id":106,"value":"https://cneos.jpl.nasa.gov/news/news210.html","pinned":false,"hidden":false,"mode":"md"},{"id":100,"value":"https://ssd-api.jpl.nasa.gov/doc/sentry.html\n\nhttps://cneos.jpl.nasa.gov/sentry/details.html#?des=2024%20YR4\n\nhttps://catalina.lpl.arizona.edu/css-orbit-view?Namev=2024%20YR4&JDTv=2460702.5&av=2.5163758&Mv=16.19143&ev=0.6616095&Iv=3.40829&Periv=134.36444&Nodev=271.36761&Pv=3.9917492271732957&qv=0&Tv=0&Cx=0&Cy=-4&Cz=1000&CZ=93\n\nhttps://en.wikipedia.org/wiki/2024_YR4\n\nhttps://groups.io/g/mpml/topic/2024_yr4_torino_scale_3/110849089\n\nSearch for 2024 YR4:\nhttps://groups.io/g/mpml/search?p=recentpostdate%2Fsticky%2C%2C%2C20%2C2%2C0%2C0&q=2024%20yr4\n\nhttps://uk.news.yahoo.com/asteroid-hit-earth-yr4-update-impact-nasa-416-asteroid-170800833.html","pinned":false,"hidden":false,"mode":"md"},{"id":393,"value":"https://ssd-api.jpl.nasa.gov/doc/sentry.html\n\n>","pinned":false,"hidden":false,"mode":"md"},{"id":180,"value":"-----\n\n-----\n","pinned":false,"hidden":false,"mode":"md"},{"id":676,"value":"ESA API: https://neo.ssa.esa.int/computer-access\n\nObservation data: https://neo.ssa.esa.int/PSDB-portlet/download?file=2024YR4.rwo\n\nhttps://neo.ssa.esa.int/PSDB-portlet/download?file=2024YR4.clolin\n\n\n\n","pinned":false,"hidden":false,"mode":"md"},{"id":440,"value":"modes = ({\n ip: {\n title: \"Probability of Impact\",\n subtitle: \"Estimated probability changing with new observations\",\n percent: true,\n label: \"Probability of impact (%)\",\n },\n palermo: {\n title: \"Palermo Scale\",\n subtitle: \"Estimated Palermo hazard scale over time\",\n percent: false, \n label: \"Palermo hazard scale\",\n },\n daysObserved: {\n title: \"Observation span\",\n subtitle: \"Number of days from first observation to last\",\n percent: false,\n label: \"Days\",\n },\n numObservations: {\n title: \"Number of Observations\",\n subtitle: \"Number of observations used in analysis\",\n percent: false,\n label: \"Number of observations\",\n },\n})\n","pinned":false,"hidden":false,"mode":"ojs"},{"id":704,"value":"{\n function m(d) {\n let nextImpact = getNextImpactData(d);\n let o = {fetched:d.fetched,...nextImpact,...d.summary,...nextImpact};\n return o;\n }\n return objectHistory.map(m);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":710,"value":"objectHistory.filter(d=>!d.data)","pinned":true,"hidden":false,"mode":"ojs"},{"id":142,"value":"$30","pinned":false,"hidden":false,"mode":"ojs"},{"id":31,"value":"impactDate = {\n let dateSplit = nextImpactData.date.split(\".\")\n let date = new Date(dateSplit[0]);\n return date;\n}\n ","pinned":false,"hidden":false,"mode":"ojs"},{"id":523,"value":"daysObserved = Number(objectDetails.summary.darc.split(\" \")[0])","pinned":true,"hidden":false,"mode":"ojs"},{"id":48,"value":"nextImpactData = getNextImpactData(objectDetails);","pinned":false,"hidden":false,"mode":"ojs"},{"id":16,"value":"mutable objectDetails = null;","pinned":true,"hidden":false,"mode":"ojs"},{"id":391,"value":"method = objectDetails.summary.method","pinned":true,"hidden":false,"mode":"ojs"},{"id":134,"value":"objectHistory = rawHistory.results.map(d=>({fetched:d.fetched,...JSON.parse(d.text,)})).concat(oldData).map(canonicalizeDetails)","pinned":true,"hidden":false,"mode":"ojs"},{"id":378,"value":"uniqueHistories.map(d=>d.data[0].ip)","pinned":true,"hidden":false,"mode":"ojs"},{"id":163,"value":"uniqueHistories = d3.reverse(objectHistory).filter((d,i,a)=> {\n if (!i) {\n return true;\n }\n const d1 = canonicalizeDetails(a[i-1]);\n delete d1.fetched ;\n delete d1.summary.pdate;\n const d2 = canonicalizeDetails(d);\n delete d2.fetched \n delete d2.summary.pdate;\n return (JSON.stringify(d1) !== JSON.stringify(d2));\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":349,"value":"compareObjects(canonicalizeDetails(uniqueHistories.slice(-1)[0]),canonicalizeDetails(uniqueHistories.slice(-2)[0]))","pinned":true,"hidden":false,"mode":"ojs"},{"id":566,"value":"compareObjects(canonicalizeDetails(objectHistory[0]),canonicalizeDetails(objectHistory[1]))","pinned":true,"hidden":false,"mode":"ojs"},{"id":368,"value":"canonicalizeDetails(uniqueHistories[1])","pinned":true,"hidden":false,"mode":"ojs"},{"id":370,"value":"canonicalizeDetails(uniqueHistories[2])","pinned":true,"hidden":false,"mode":"ojs"},{"id":346,"value":"function compareObjects(o1,o2) {\n let d1 = {};\n let d2 = {};\n Object.keys(o1).forEach(k=>{\n if (k in o2) {\n if (o1[k] === o2[k]) {\n return ;\n }\n if (typeof(o1[k])== \"object\" && o1[k] && typeof(o2[k])== \"object\" && o2[k]) {\n let c = compareObjects(o1[k],o2[k]);\n if (Object.keys(c.d1).length) {\n d1[k] = c.d1; \n }\n if (Object.keys(c.d2).length) {\n d2[k] = c.d2;\n }\n return;\n }\n d1[k] = o1[k];\n d2[k] = o2[k]\n }\n else {\n d1[k] = o1[k];\n }\n });\n Object.keys(o2).forEach(k=>{\n if (!(k in o1)) {\n d2[k] = o2[k];\n }\n });\n return {d1,d2};\n}\n","pinned":true,"hidden":false,"mode":"ojs"},{"id":231,"value":"{\n while (true) {\n yield await checkForChanges() ;\n yield Promises.tick(5*1000*60);\n }\n}\n","pinned":true,"hidden":false,"mode":"ojs"},{"id":138,"value":"function getNextImpactData(objDetails) {\n return d3.sort(objDetails.data,d=>d.date)[0];\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":5,"value":"config =({\n apiURL: \"https://ssd-api.jpl.nasa.gov/sentry.api\",\n objDes: \"2024%20YR4\",\n});","pinned":true,"hidden":false,"mode":"ojs"},{"id":13,"value":"async function getObjectDetails(des, trackChanges = false) {\n let url = config.apiURL + \"?des=\" + des;\n url = getProxyURL(url, false, trackChanges);\n const response = await fetch(url);\n let json = await response.json();\n return canonicalizeDetails(json);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":580,"value":"JSON.stringify(null)","pinned":true,"hidden":false,"mode":"ojs"},{"id":55,"value":"$31","pinned":true,"hidden":false,"mode":"ojs"},{"id":130,"value":"rawHistory = getHistory()","pinned":true,"hidden":false,"mode":"ojs"},{"id":575,"value":"{\n if (objectHistory && objectHistory.length && !objectDetails) {\n mutable objectDetails = objectHistory[0]; \n }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":323,"value":"$32","pinned":true,"hidden":false,"mode":"ojs"},{"id":127,"value":"async function getHistory(des = config.objDes) {\n objectDetails;\n let url = config.apiURL + \"?des=\" + des;\n console.log(\"getting history of \"+url);\n let r = await getURLhistory(url);\n return r; \n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":74,"value":"function isObject(obj) {\n return typeof obj === 'object' && obj !== null;\n}\n","pinned":true,"hidden":false,"mode":"ojs"},{"id":357,"value":"function canonicalizeDetails(o) {\n return {\n data: d3.sort(o.data,d=>d.date, d=>d.ps).map(deepCopyWithSort),\n signature:deepCopyWithSort(o.signature),\n summary: deepCopyWithSort(o.summary),\n fetched: o.fetched,\n } \n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":359,"value":"objectHistory[0]","pinned":true,"hidden":false,"mode":"ojs"},{"id":66,"value":"function deepCopyWithSort(i) {\n if (! isObject(i)) {\n return i;\n }\n if (Array.isArray(i)) {\n return i.map(deepCopyWithSort);\n }\n let o = {};\n d3.sort(Object.keys(i)).forEach(k=>{\n o[k] = deepCopyWithSort(i[k]);\n });\n return o; \n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":68,"value":"canonicalizeDetails(objectDetails)","pinned":true,"hidden":false,"mode":"ojs"},{"id":58,"value":"objectDetailsJSON = {\n let d = canonicalizeDetails(objectDetails) ;\n delete d.fetched;\n return JSON.stringify(d);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":10,"value":"import {getProxyURL, getURLhistory} from \"@labvegas/cors\"","pinned":false,"hidden":false,"mode":"ojs"},{"id":269,"value":"viewof sigmaRange = Inputs.range([0.005, 2], {label: \"Sigma\", step: 0.005, value:1})","pinned":true,"hidden":false,"mode":"ojs"},{"id":398,"value":"viewof xRange = Inputs.range([-1, 0], {label: \"Distance from mean\", step: 0.01, value:-1})","pinned":true,"hidden":false,"mode":"ojs"},{"id":418,"value":"viewof radiusOfImpact = Inputs.range([0.001, 0.2], {label: \"Radius for impact\", step: 0.001, value:0.01})","pinned":true,"hidden":false,"mode":"ojs"},{"id":242,"value":"$33","pinned":false,"hidden":false,"mode":"ojs"},{"id":468,"value":"daysUntilImpact = 8*365.25 - 4;","pinned":true,"hidden":false,"mode":"ojs"},{"id":486,"value":"randDataSigma = 1;","pinned":true,"hidden":false,"mode":"ojs"},{"id":479,"value":"function pathProb(samples,sigma,line,) {\n let p = 1;\n samples.forEach((sample,i)=>{\n p = updatePathProb(p,sample,sigma,line);\n });\n return p;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":587,"value":"function updatePathProb(p,sample,sigma,line,) {\n const lineY = line.intercept + line.slope * sample.x;\n const pi = normDistUnscaled(sample.y-lineY,0,sigma);\n return p * pi;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":600,"value":"function updatePathProbs(sample,sigma, a=pathProbs){\n let finalProbs = {};\n let totalP = 0;\n a.forEach(d=>{\n d.p = updatePathProb(d.p,sample,sigma,d.line);\n finalProbs[d.line.finalY] = (finalProbs[d.line.finalY] || 0) + d.p;\n totalP += d.p;\n });\n let probData = Object.entries(finalProbs).map(kv=>{\n let y = Number(kv[0]);\n let p = kv[1]/totalP;\n return {\n x: sample.x,\n y,\n p\n };\n });\n return probData;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":615,"value":"allFinalProbs = calcAllFinalProbs()","pinned":true,"hidden":false,"mode":"ojs"},{"id":612,"value":"function calcAllFinalProbs(samples=randData, sigma=1, pathProbs=null) {\n if (!pathProbs) {\n pathProbs = initPathProbs();\n }\n //return pathProbs;\n let a = [];\n samples.forEach(sample=>{\n // TODO: Find peak probability and position of it\n a.push(updatePathProbs(sample,sigma,pathProbs));\n });\n return a; \n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":533,"value":"positionDist = d3.randomNormal(0,randDataSigma);","pinned":true,"hidden":false,"mode":"ojs"},{"id":471,"value":"randData = {\n let data = d3.range(0,daysUntilImpact).map(x=>{\n let y = positionDist();\n return {\n x,\n y,\n };\n });\n return data;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":531,"value":"function changeDay(day) {\n randData[day].y = positionDist();\n return randData[day].y;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":537,"value":"dayChanged = changeDay(daysRange-1);","pinned":true,"hidden":false,"mode":"ojs"},{"id":474,"value":"viewof daysRange = Inputs.range([2, daysUntilImpact], {label: \"Days of observation\", step: 1, value: Math.floor(daysObserved)})","pinned":true,"hidden":false,"mode":"ojs"},{"id":484,"value":"{\n return \"disabled\";\n dayChanged;\n\n let plotData = finalProbs;\n\n let p0 = plotData.find(d=>d.y==0).p;\n let p2 = plotData.find(d=>d.y==2).p;\n let pm2 = plotData.find(d=>d.y==-2).p;\n //return plotData;\n return Plot.plot({\n title: \"Predicted probability of final position with \" + daysRange + \" days of observation.\",\n subtitle: html`P(-2): ${Math.round(pm2*100000)/1000}%
P(0): ${Math.round(p0*100000)/1000}%
P(2): ${Math.round(p2*100000)/1000}%`,\n marginLeft: 55,\n marginRight: 55,\n width,\n x: {\n grid: true,\n label: \"Position\"\n },\n y: {\n label: \"Probability\",\n grid: true,\n percent: true,\n },\n marks: [\n Plot.dot(plotData, {x: d=>d.y, y: d=>d.p, tip:true}),\n ]\n });\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":562,"value":"peakFinalProb = finalProbs[d3.maxIndex(finalProbs,d=>d.p)]","pinned":true,"hidden":false,"mode":"ojs"},{"id":555,"value":"finalProbs = calcFinalProbs(randData,daysRange);\n","pinned":true,"hidden":false,"mode":"ojs"},{"id":548,"value":"function calcFinalProbs(data, days) {\n let regData = data.slice(0,days);\n let y0max = 4/Math.sqrt(days);\n //let yFinalMax = 3*y0max * daysUntilImpact / days ;\n //let yFinalMax = 2*Math.sqrt(daysUntilImpact);\n let yFinalMax = 100;\n \n let steps = 100;\n let totalP = 0;\n\n let r = {};\n for (let y0 = -y0max ; y0 <= y0max ; y0 += y0max/steps*2) {\n for (let y1 = -yFinalMax ; y1 <= yFinalMax ; y1 += yFinalMax/steps*2) {\n let slope = (y1 - y0) / daysUntilImpact ;\n let p = pathProb(regData,randDataSigma,{intercept:y0,slope, finalY:y1});\n totalP += steps*p;\n r[y1] = (r[y1] || 0) + steps*p;\n }\n }\n let probData = Object.entries(r).map(kv=>{\n return {\n y: Number(kv[0]),\n p: kv[1]/totalP\n };\n });\n return probData;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":593,"value":"pathProbs = initPathProbs()","pinned":true,"hidden":false,"mode":"ojs"},{"id":591,"value":"function initPathProbs(yFinalMax=100,steps=100,y0max = 5, y0steps = 20) {\n let a = [];\n for (let y1 = -yFinalMax ; y1 <= yFinalMax ; y1 += yFinalMax/steps*2) {\n for (let y0 = -y0max ; y0 <= y0max ; y0 += y0max/y0steps*2) {\n let slope = (y1 - y0) / daysUntilImpact ;\n a.push({\n p:1,\n line: {intercept:y0,slope, finalY: y1},\n });\n }\n }\n return a;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":424,"value":"$34","pinned":true,"hidden":false,"mode":"ojs"},{"id":245,"value":"function normDist(x,mean=0,sigma=1) {\n const x1 = (x - mean)/sigma;\n const a = 1 / Math.sqrt(2*Math.PI)/sigma;\n return Math.exp(-x1*x1/2) * a ;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":512,"value":"function normDistUnscaled(x,mean=0,sigma=1) {\n const x1 = (x - mean)/sigma;\n return Math.exp(-x1*x1/2) ;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":436,"value":"ML = require(\"https://www.lactame.com/lib/ml/6.0.0/ml.min.js\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":661,"value":"constants = ({\n au: 149597870700, // meters https://en.wikipedia.org/wiki/Astronomical_unit\n ld: 385000000, // https://en.wikipedia.org/wiki/Lunar_distance\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":664,"value":"constants.au / constants.ld","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W35","stdlib":"1","titling":"auto"}