在d3.js中创建一个弧 [英] making an arc in d3.js

问题描述

我使用javascript库d3.js（;

I am using the javascript library d3.js (http://d3js.org/) to create canvas data visualizations. I'm trying to make an arc, but it's not accepting the data parameters from my array. Does anyone know what I'm doing wrong? This is my code:

var chartConfig = { "canvasSize" : 800 }

var radius = chartConfig.canvasSize / 2;
var pi = Math.PI;

var vis = d3.select("#chart").append("svg")
    .attr("width", radius * 2)
    .attr("height", radius * 2)
    .append("g")
    .attr("transform", "translate(" + radius + "," + radius + ")");

var arcData = [
  {aS: 0, aE: 45,rI:radius/2,rO:radius}
];
var arc = vis.selectAll("arc").data(arcData).enter().append("arc");
arc.attr("innerRadius", function(d){d.rI}).attr("outerRadius",function(d){d.rO}).attr("class","arc");

function degToRad(degrees){
  return degrees * (pi/180);
}

解决方案

There is no arc element in SVG, you need to define the appropriate path element. Luckily there is a d3 helper function to do this.

var arc = d3.svg.arc()
    .innerRadius(50)
    .outerRadius(70)
    .startAngle(45 * (Math.PI/180)) //converting from degs to radians
    .endAngle(3) //just radians

vis.append("path")
    .attr("d", arc)
    .attr("transform", "translate(200,200)")

Working example at http://jsfiddle.net/g0r9n090/;

这篇关于在d3.js中创建一个弧的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！