I'm trying to do a simple polar scatter plot like this one : http://helpcentral.componentone.com/NetHelp/SpreadNet6/WF/artwork/plottypes-polar-point2.png
I found that answer Polar plots using D3.js but I cannot display the points instead of d3.svg.line.radial. How do I change the line to points?
See Question&Answers more detail:os
If you are using the d3.svg.line.radial() to generate you polar plot, one easy solution would be to parse the generated path to get point coordinates, then add a circle at those coordinates:
var line = d3.svg.line.radial()
.radius(function(d) {
return r(d[1]);
})
.angle(function(d) {
return -d[0] + Math.PI / 2;
});
svg.selectAll("point")
.data(data)
.enter()
.append("circle")
.attr("class", "point")
.attr("transform", function(d) {
// use the line function and parse out the coordinates
var coors = line([d]).slice(1).slice(0, -1);
return "translate(" + coors + ")"
})
.attr("r", 8);
Here's a full working example:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.frame {
fill: none;
stroke: #000;
}
.axis text {
font: 10px sans-serif;
}
.axis line,
.axis circle {
fill: none;
stroke: steelblue;
stroke-dasharray: 4;
}
.axis:last-of-type circle {
stroke: steelblue;
stroke-dasharray: none;
}
.line {
fill: none;
stroke: orange;
stroke-width: 3px;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var width = 960,
height = 500,
radius = Math.min(width, height) / 2 - 30;
var r = d3.scale.linear()
.domain([0, 1])
.range([0, radius]);
var line = d3.svg.line.radial()
.radius(function(d) {
return r(d[1]);
})
.angle(function(d) {
return -d[0] + Math.PI / 2;
});
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");
var gr = svg.append("g")
.attr("class", "r axis")
.selectAll("g")
.data(r.ticks(3).slice(1))
.enter().append("g");
gr.append("circle")
.attr("r", r);
var ga = svg.append("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);
var color = d3.scale.category20();
var line = d3.svg.line.radial()
.radius(function(d) {
return r(d[1]);
})
.angle(function(d) {
return -d[0] + Math.PI / 2;
});
var data = [
[Math.PI / 3, Math.random()],
[Math.PI / 6, Math.random()],
[0 * Math.PI, Math.random()],
[(11 * Math.PI) / 6, Math.random()],
[(5 * Math.PI / 3), Math.random()],
[(3 * Math.PI) / 2, Math.random()],
[(4 * Math.PI / 3), Math.random()],
[(7 * Math.PI) / 6, Math.random()],
[Math.PI, Math.random()],
[(5 * Math.PI) / 6, Math.random()],
[(2 * Math.PI) / 3, Math.random()],
[Math.PI / 2, Math.random()]
]
svg.selectAll("point")
.data(data)
.enter()
.append("circle")
.attr("class", "point")
.attr("transform", function(d) {
var coors = line([d]).slice(1).slice(0, -1);
return "translate(" + coors + ")"
})
.attr("r", 8)
.attr("fill",function(d,i){
return color(i);
});
</script>