Published
Edited
Feb 24, 2020
4 stars
chart = {
const svg = d3.select(DOM.svg(width, height + bottomBarHeight + margin.bottom * 2));
const initialHoldings = {quantity: 100, price: 90}
svg.append("g").call(xAxis);
svg.append("g").call(xAxisBuySell);
svg.append("g").call(yAxis);
svg.append("g").call(yAxis2);
svg.append('line')
.attr('x1', margin.left)
.attr('y1', buySellY(0))
.attr('x2', width - margin.right)
.attr('y2', buySellY(0))
.attr('stroke', '#1b1e23')
.attr('stroke-opacity', 0.2)
svg.append("g")
.selectAll("rect")
.data(transactions)
.join("rect")
.attr("x", (d, i) => x(d.date))
.attr("y", d => d.value > 0 ? buySellY(d.value) : buySellY(d.value) - Math.abs(buySellY(0) - buySellY(d.value)))
.attr("height", d => Math.abs(buySellY(0) - buySellY(d.value)))
.attr("width", 10)
.attr("fill", d => d.value > 0 ? 'green' : 'red')
.on("click", d => setDatum(d))
// Make price chart
const positionSize = 2
const [notHolding, holding] = _.partition(data, ({date}) =>
buyDatum.quantity > 0 ? date < buyDatum.date : date > buyDatum.date)
const priceChartSegments = [
{color: 'rgba(27, 30, 35, 0.6)', data: notHolding, dashed: true},
{color: 'green', data: holding, dashed: false},
]
priceChartSegments.forEach(({data, color, dashed}) =>
svg.append("path")
.datum(data)
.attr("fill", "none")
.attr("stroke", color)
.attr("stroke-width", dashed ? 1 : positionSize)
.attr("stroke-linejoin", "round")
.attr("stroke-linecap", "round")
.attr("d", d3.line()
.x(d => x(d.date))
.y(d => y(d.value)))
.style('stroke-dasharray', dashed ? '3,3' : null)
)
;[buyDatum].forEach(bD => {
// pre
const preColor = bD.quantity > 0 ? 'green' : 'rgba(27, 30, 35, 0.6)'
svg.append('line')
.attr('x1', margin.left)
.attr('y1', y(bD.value))
.attr('x2', x(bD.date))
.attr('y2', y(bD.value))
.attr('stroke', preColor)
.attr('stroke-width', bD.quantity > 0 ? positionSize : 1)
.style("stroke-dasharray", '3,3')
// post
const postColor = bD.quantity > 0 ? 'rgba(27, 30, 35, 0.6)' : 'green'
svg.append('line')
.attr('x1', x(bD.date))
.attr('y1', y(bD.value))
.attr('x2', width - margin.right)
.attr('y2', y(bD.value))
.attr('stroke', postColor)
.attr('stroke-width', bD.quantity > 0 ? 1 : positionSize)
.style("stroke-dasharray", '3,3')
})
// Make right hand side tag for transaction
if (buyDatum.quantity < 0) {
svg.append("rect")
.attr('x', width - margin.right)
.attr('y', y(buyDatum.value) - 6)
.attr('fill', buyDatum.quantity > 0 ? 'black' : 'green')
.attr('width', `${margin.right}px`)
.attr('height', '12px')
svg.append("text")
.attr('x', width - margin.right + 6)
.attr('y', y(buyDatum.value))
.attr('font-size', '10px')
.attr('fill', 'white')
.attr("dy", ".32em")
.attr('text-anchor', 'start')
.text(format(Math.abs(buyDatum.quantity) * buyDatum.value));
}
// Make left hand side tag for transaction
if (buyDatum.quantity > 0) {
svg.append("rect")
.attr('x', 0)
.attr('y', y(buyDatum.value) - 6)
.attr('fill', 'green')
.attr('width', `${margin.right}px`)
.attr('height', '12px')
svg.append("text")
.attr('x', margin.right - 6)
.attr('y', y(buyDatum.value))
.attr('font-size', '10px')
.attr('fill', 'white')
.attr("dy", ".32em")
.attr('text-anchor', 'end')
.text(format(Math.abs(buyDatum.quantity) * buyDatum.value));
}
// Make tag for security
if (buyDatum.quantity > 0) {
svg.append("rect")
.attr('x', width - margin.right)
.attr('y', y(_.last(data).value) - 6)
.attr('fill', 'green')
.attr('width', `${margin.right}px`)
.attr('height', '12px')
svg.append("text")
.attr('x', width - margin.right + 6)
.attr('y', y(_.last(data).value))
.attr('font-size', '10px')
.attr('fill', 'white')
.attr("dy", ".32em")
.attr('text-anchor', 'start')
.text(format(
buyDatum.quantity * _.last(data).value
));
}
// Make tag for initial holdings
if (buyDatum.quantity < 0) {
svg.append("rect")
.attr('x', 0)
.attr('y', y(data[0].value) - 6)
.attr('fill', 'green')
.attr('width', `${margin.left}px`)
.attr('height', '12px')
svg.append("text")
.attr('x', margin.left - 6)
.attr('text-anchor', 'end')
.attr('y', y(data[0].value))
.attr('font-size', '10px')
.attr('fill', 'white')
.attr("dy", ".32em")
.text(format(
initialHoldings.quantity * initialHoldings.price
));
}
return svg.node();
}
_ = require('lodash')
transactions = {
const parse = d3.timeParse("%Y-%m-%d")
return [
{value: -50, date: parse('2009-06-04')},
{value: 100, date: parse('2010-07-04')},
{value: 100, date: parse('2010-09-13')},
{value: -100, date: parse('2011-01-13')},
]
}
toBuyDatum = t => ({
..._.findLast(data, ({date}) => date <= t.date),
quantity: t.value
})
mutable buyDatum = ({
..._.findLast(data, ({date}) => date <= transactions[1].date),
quantity: transactions[1].value
})
function setDatum(transaction) {
console.log('setting', transaction)
mutable buyDatum = ({
..._.findLast(data, ({date}) => date <= transaction.date),
quantity: transaction.value
})
}
height = 600
bottomBarHeight = 120
margin = ({top: 20, right: 50, bottom: 30, left: 50})
x = d3.scaleUtc()
.domain(d3.extent(data, d => d.date))
.range([margin.left, width - margin.right])
y = d3.scaleLinear()
.domain([d3.min(data, d => d.value), d3.max(data, d => d.value)])
.range([height - margin.bottom, margin.top])
buySellY = {
const extreme = d3.max(transactions, d => Math.abs(d.value))
return d3.scaleLinear()
.domain([-extreme, extreme])
.range([height + bottomBarHeight - margin.bottom, height])
}
buySellX = d3.scaleBand()
.domain(d3.timeDays(data[0].date, _.last(data).date))
.rangeRound([0, width], .1);
y2 = {
const adjVals = data.map(({value}) => Math.abs(buyDatum.quantity) * value)
return d3.scaleLinear()
.domain([d3.min(adjVals), d3.max(adjVals)])
.range([height - margin.bottom, margin.top])
}
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0))
.call(g => g.select(".domain").remove())
xAxisBuySell = g => g
.attr("transform", `translate(0,${height + bottomBarHeight - margin.bottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0))
.call(g => g.select(".domain").remove())
yAxis = g => g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y)
.tickValues(d3.ticks(...y.domain(), 10))
.tickFormat(x => x))
.call(g => g.selectAll(".tick line").clone()
.attr("stroke-opacity", d => d === 1 ? null : 0.2)
.attr("x2", width - margin.left - margin.right))
.call(g => g.select(".domain").remove())
yAxis2 = {
return g => g
.attr("transform", `translate(${width - margin.right},0)`)
.call(d3.axisRight(y)
.tickValues(d3.ticks(...y.domain(), 10))
.tickFormat(x => x))
.call(g => g.select(".domain").remove())
}
format = {
const nf = Intl.NumberFormat(undefined, {style: 'currency', currency: 'USD'})
return x => {
if (x >= 1e9) return `${nf.format(x / 1e9)}B`
if (x >= 1e6) return `${nf.format(x / 1e6)}M`
if (x >= 1e3) return `${nf.format(x / 1e3)}K`
return nf.format(x)
}
}
data = Object.assign(d3.csvParse(await FileAttachment("aapl.csv").text(), d3.autoType).map(({date, close}) => ({date, value: close})), {y: "$ Close"})
d3 = require("d3@5")
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