COVID-19 Spreading trends / Yong-Yeol Ahn

description: `You can view the trend in the past by going back. The starting point of the slider is ${formatDate(startDate)}, and the end point is ${formatDate(goBackEnd)}.`

})

s.input.style.width = "40%";

return s;

}

function onMouseOver(selected) {

const country_code = d3.select(this).attr("class");

d3.selectAll(`.${country_code}`).attr("fill-opacity", 1).attr("stroke-opacity", 1).attr("stroke-width", 3)

.attr("r", 5);

d3.select("#fullname").text(code_to_name(country_code))

.style("text-anchor", "end")

.attr("font-size", 50).attr("fill-opacity", 0.1).attr("fill", "black")

.attr("font-style", "bold")

.attr("font-family", "Helvetica, sans-serif")

.attr("x", x(params.xmax)).attr("y", y(params.ymin)-20);

const circle = d3.select(`circle.${country_code}`);

//d3.select("#guides").attr("transform", `translate(${circle.attr("cx")} ${-circle.attr("cy")})`)

}

function onMouseOut() {

const country_code = d3.select(this).attr("class");

d3.selectAll(`.${country_code}`)

.attr("fill-opacity", params.opac_weak).attr("stroke-opacity", params.opac_weak).attr("stroke-width", 1)

.attr("r", 3);

d3.select("#fullname").attr("fill-opacity", 0);

d3.select("#guides").attr("transform", `translate(0 0)`)

}

function draw_axes(svg) {

svg.append("g").call(xAxis);

svg.append("g").call(yAxis);

}

function draw_trajectories(svg) {

svg.append("g").selectAll("path").data(viz_data).join("path")

.attr("class", d => `${d.country_code}`)

.attr("stroke", d => color(d.region)).attr("fill", "none")

.attr("stroke-opacity", params.opac_weak)

.attr("d", d => get_path(d.shifted))

.on("mouseover", onMouseOver).on("mouseout", onMouseOut)

svg.append("g").selectAll("circle").data(viz_data).join("circle")

.attr("class", d => `${d.country_code}`)

.attr("fill", d => color(d.region)).attr("fill-opacity", params.opac_weak)

.attr("cx", d => x(d.shifted.length-1)).attr("cy", d => y(d.shifted[d.shifted.length - 1])).attr("r", 3)

.on("mouseover", onMouseOver).on("mouseout", onMouseOut);

svg.append("g").selectAll("text").data(viz_data).join("text").text(d => d.country_code)

.attr("class", d => d.country_code)

.attr("fill", d => color(d.region)).attr("fill-opacity", params.opac_weak)

.attr("x", d => d3.min( [x(d.shifted.length-1)+4, x(params.xmax)-10] ))

.attr("y", d => y(d.shifted[d.shifted.length - 1]))

.on("mouseover", onMouseOver).on("mouseout", onMouseOut);

}

function draw_doubling_lines(svg) {

// (0, params.ymin) -> (params.xmax, Math.pow(2, params.ymin*params.xmax/period))

// every day doubling -> (1, params.ymin*2), (2, params.ymin*2*2), ...

svg.append("g").attr("id", "guides").selectAll("path").data(doubling_periods).join("path")

.attr("class", "guidelines")

.attr("stroke", "orange").attr("stroke-opacity", 0.8).attr("stroke-dasharray", 2)

.attr("d", d => d3.line()([

[x(0), y(params.ymin)],

[x(params.xmax), y(params.ymin*Math.pow(2, params.xmax/d))]

]));

svg.append("g").selectAll("text").data(doubling_period_labels).join("text")

.text(d => d.period > 1 ? `Doubling every ${d.period} days`: "Doubling every day")

.attr("font-size", 12)

.style("text-anchor", "end")

.attr("fill", "orange")

.attr("transform", d => `rotate(${get_text_rotation_angle(d.period)} ${x(d.x)} ${y(d.y)})`)

.attr("x", d => x(d.x))

.attr("y", d => y(d.y));

}

doubling_period_labels = doubling_periods.map(function(d) {

d = Number(d);

const candidate_n = params.xmax / d;

const candidate_y = Math.pow(2, candidate_n) * params.ymin;

if (candidate_y < params.ymax) {

return { 'period': d, 'x': params.xmax, 'y': candidate_y };

} else {

return { 'period': d, 'x': Math.log2(params.ymax/params.ymin) * d, 'y': params.ymax };

}

});

function draw_date(svg) {

svg.append("g") // Date

.append("text").text(d3.timeFormat("%b %d %Y")(d3.timeDay.offset(startDate, goBack)))

.style("text-anchor", "end")

.attr("font-size", 50).attr("fill-opacity", 0.2)

.attr("font-style", "bold")

.attr("font-family", "Helvetica, sans-serif")

.attr("x", x(params.xmax) + params.margin.right)

.attr("y", y(params.ymax) + params.margin.top);

}

function get_path(d) {

const l = d3.line();

return l(d.map(function(e, i) { return [x(i), y(e)] }));

}

color = d3.scaleOrdinal(data.map(d => d.region), ["#1f77b4","#ff7f0e","#2ca02c","#d62728","#9467bd","#8c564b","#e377c2","#17becf"])

// color = d3.scaleOrdinal(data.map(d => d.region), d3.schemeTableau10).unknown("black")

//d3.schemeCategory10, d3.schemeTableau10

yAxis = g => g

.attr("transform", `translate(${params.margin.left},0)`)

.call(d3.axisLeft(y).ticks(params.height/80, ","))

.call(g => g.append("text")

.attr("font-size", 15)

.attr("x", -params.margin.left)

.attr("y", params.margin.top-10)

.attr("fill", "currentColor")

.attr("text-anchor", "start")

.text(`↑ Number of ${y_type}`))

y = d3.scaleLog([params.ymin, params.ymax], [params.height - params.margin.bottom, params.margin.top])

xAxis = g => g

.attr("transform", `translate(0,${params.height - params.margin.bottom})`)

.call(d3.axisBottom(x).ticks(width/80))

.call(g => g.append("text")

.attr("x", params.width)

.attr("y", params.margin.bottom - 4)

.attr("font-size", 15)

.attr("fill", "currentColor")

.attr("text-anchor", "end")

.text(`Days since ${pivot_values[pivot_n]} ${y_type}→`))

x = d3.scaleLinear().domain([params.xmin, params.xmax])

.range([params.margin.left, params.width - params.margin.right]);

function get_text_rotation_angle(doubling_period) {

const radians = 0.0174532925;

return -Math.atan( (y(params.ymin)-y(params.ymin*2))/(x(doubling_period)-x(0)) ) / radians;

}

function code_to_name(country_code) {

return data.find(d => d.country_code === country_code).country_name;

}

function name_to_code(country_name) {

return data.find(d => d.country_name === country_name).country_code;

}

viz_data = filtered_data.filter(d => selected_regions.includes(d.region)).filter(d => d[y_type][last_index][1] > pivot).map(function(d) {

const start_idx = pivot_bisector.right(d[y_type], pivot);

d['shifted'] = d[y_type].slice(start_idx).map(d => d[1]);

return d;

})

pivot_bisector = d3.bisector(d => d[1])

countryNameList = {

let list = [];

for (let i = 0; i < data.length; i++) {

list.push(data[i].country_name)

}

return list;

}

pivot = pivot_values[pivot_n]

pivot_values = [1, 5, 10, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 13000, 15000, 20000, 50000, 100000]

today = all_dates[all_dates.length - 1];

parseTime = d3.timeParse("%Y-%m-%d");

all_dates = data[0]['confirmed'].map(x => parseTime(x[0]));

// startDate = d3.timeDay(new Date(2019, 11, 31))

startDate = parseTime(data[0].confirmed[0][0])

d3.timeDay.count(startDate, parseTime("2020-01-02"))

d3.timeDay.count(startDate, today)

d3.timeDay(parseTime(data[0].confirmed[10][0]))

d3.timeDay.count(d3.timeDay(parseTime(data[0].confirmed[0][0])), today)

formatDate = d3.timeFormat("%Y-%m-%d")

last_index = goBack

filtered_data = data.map(function(d) {

return {

'country_code': d.country_code,

'country_name': d.country_name,

'population': d.population,

'region': d.region,

'confirmed': d.confirmed.filter(e => d3.timeDay.count(startDate, parseTime(e[0])) <= goBackSpan),

'deaths': d.deaths.filter(e => d3.timeDay.count(startDate, parseTime(e[0])) <= goBackSpan),

'confirmed_fraction': d.confirmed_fraction.filter(e => d3.timeDay.count(startDate, parseTime(e[0])) <= goBackSpan),

'confirmed_lastweek': d.confirmed_lastweek.filter(e => d3.timeDay.count(startDate, parseTime(e[0])) <= goBackSpan),

'deaths_lastweek': d.deaths_lastweek.filter(e => d3.timeDay.count(startDate, parseTime(e[0])) <= goBackSpan),

}

})

data = data_raw.filter(d => d.country_code != 'OWID_WRL' && d.region !== null).map(function(d) {

d.confirmed_fraction = d.confirmed.map(x => [x[0], x[1] / d.population]);

d.confirmed_lastweek = past_week(d.confirmed);

d.deaths_lastweek = past_week(d.deaths);

return d;

})

function past_week(a) {

var new_array = [[a[0][0], a[0][1]]];

var curr_sum = 0;

var min_idx = 0;

for (var i = 1; i < a.length; i++) {

min_idx = d3.max([0, i-7]);

if (min_idx != 0) {

curr_sum = a[i][1] - a[min_idx][1];

} else {

curr_sum = a[i][1];

}

new_array.push([ a[i][0], curr_sum ])

}

return new_array;

}

data_raw = d3.json("https://raw.githubusercontent.com/hongtaoh/covid19-data/master/output/cntry_stat_owid.json")

import { rangeSlider as rangeSlider } from '@mootari/range-slider'

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