chart = {
const svg = d3.select(DOM.svg(width, height));
svg
.selectAll("circle.bid")
.data(data)
.enter()
.append("circle")
.attr("fill", "#456")
.attr("opacity", "0.5")
.attr("class", "bid")
.attr("r", d => r(d.bidSize))
.attr("cx", d => x(d.recv))
.attr("cy", d => y(d.bidPrice));
svg.append("g").call(xAxis);
svg.append("g").call(yAxis);
return svg.node();
}
s = require("socket.io-client/dist/socket.io.js")
data = {
const socket = s("https://ws-api.iextrading.com/1.0/tops");
socket.on("connect", () => {
socket.emit("subscribe", ticker);
});
let prices = [];
return Generators.observe(change =>
socket.on("message", msg => {
prices.push({
recv: new Date(),
...JSON.parse(msg)
});
if (prices.length > 100) prices.unshift();
change(prices);
})
);
}
yAxis = g =>
g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y).tickFormat(d3.format("$0,")))
.call(g => g.select(".domain").remove())
.call(g =>
g
.select(".tick:last-of-type text")
.clone()
.attr("x", 3)
.attr("text-anchor", "start")
.attr("font-weight", "bold")
.text(data.y)
)
xAxis = g =>
g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(
d3
.axisBottom(x)
.ticks(width / 80)
.tickSizeOuter(0)
)
.call(g => g.select(".domain").remove())
y = d3
.scaleLinear()
.nice(5)
.range([height - margin.bottom, margin.top])
.domain(d3.extent(data, d => d.bidPrice))
r = d3
.scaleSqrt()
.nice(5)
.range([3, 15]).domain(d3.extent(data, d => d.bidSize))
x = d3
.scaleTime()
.domain(d3.extent(data, d => d.recv))
.range([margin.left, width - margin.right])
margin = ({ top: 20, right: 20, bottom: 30, left: 50 })
win = 60000
height = 400
d3 = require("d3@5")
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