Design Technologist
plot([(t) => Math.sin(4 * t), (t) => Math.sin(2 * t)])
function plot(fns = [(t) => t], options = {}) {
if (!Array.isArray(fns)) {
fns = [fns];
}
const {
width = 500,
height = 500,
domain = [0, 1],
resolution = 0.01
} = options;
const { radius = Math.min(width, height) / 2 - 30 } = options;
const svg = d3.create("svg").attr("width", width).attr("height", height);
const content = svg
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");
const scale = d3.scaleLinear().domain(domain).range([0, radius]);
const grid = (g) => {
const gr = g
.attr("class", "r axis")
.selectAll("g")
.data(scale.ticks(5).slice(1))
.enter()
.append("g");
gr.append("circle").attr("r", scale);
gr.append("text")
.attr("y", function (d) {
return -scale(d) - 4;
})
.attr("transform", "rotate(15)")
.style("text-anchor", "middle")
.text(function (d) {
return d;
});
};
const axis = (g) => {
const ga = g
.attr("class", "a axis")
.selectAll("g")
.data(d3.range(0, 360, 30))
.enter()
.append("g")
.attr("transform", function (d) {
return "rotate(" + -d + ")";
});
ga.append("line").attr("x2", radius);
ga.append("text")
.attr("x", radius + 6)
.attr("dy", ".35em")
.style("text-anchor", function (d) {
return d < 270 && d > 90 ? "end" : null;
})
.attr("transform", function (d) {
return d < 270 && d > 90 ? "rotate(180 " + (radius + 6) + ",0)" : null;
})
.text(function (d) {
return d + "°";
});
};
const line = d3
.lineRadial()
.radius((d) => scale(d[1]))
.angle((d) => -d[0] + Math.PI / 2);
const curve = (g) => {
fns.forEach((fn) => {
const signal = d3
.range(0, 2 * Math.PI, resolution)
.map((t) => [t, fn(t)]);
g.append("path").datum(signal).attr("class", "line").attr("d", line);
});
};
content.append("g").call(grid);
content.append("g").call(axis);
content.append("g").attr("class", "data").call(curve);
const svgNode = svg.node();
const doc = html`
<style>
.axis text {
font: 10px sans-serif;
}
.axis line,
.axis circle {
fill: none;
stroke: #777;
stroke-dasharray: 1,4;
}
.axis :last-of-type circle {
stroke: #ddd;
stroke-dasharray: none;
}
.line {
fill: none;
stroke: #3B5FD7;
stroke-width: 1.5px;
}
.data > .line:nth-child(2) {
stroke: #e14747;
}
.data > .line:nth-child(3) {
stroke: #eac13b;
}
.data > .line:nth-child(3) {
stroke: #2f9666;
}
</style>
<div id="container">
<div class="chart">${svgNode}</div>
</div>
`;
return doc;
}
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