Chord - startAngle

viz.ch().startAngle

This method sets the starting angle for the group circular segments.

The diagram on the left uses the default 0 and the diagram on the right uses π.

Part of a series of examples on Chord diagram using VizJS

<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
  font: 10px sans-serif;
}

svg text{
  fill:grey;
  text-anchor:middle;
  font-size:18px;
}
svg .values text{
  pointer-events:none;
  stroke-width: 0.5px;
}
.groups:hover{
  cursor:pointer;
  font-weight:bold;
}
</style>
<body>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="https://vizjs.org/viz.v1.1.0.min.js"></script>
<script>

var data = [
 ["US","Canada",343] ,["US","China",27]
,["US","India",3],["US","UK",212]
,["Canada","China",9],["Canada","India",2]
,["Canada","UK",86],["Canada","US",842]
,["UK","Canada",607],["UK","China",9]
,["UK","India",5],["UK","US",715]
,["China","Canada",711],["China","India",7]
,["China","UK",183],["China","US",2104]
,["India","Canada",621],["India","China",9]
,["India","UK",777],["India","US",1969]
];

var colors = {
   "US":"rgb(193,161,111)"
  ,"Canada":"rgb(115,146,17)"
  ,"UK":"rgb(234,193,36)"
  ,"China":"rgb(217,36,5)"
  ,"India":"rgb(53,99,235)"
};

var height=700, width=1050;
var svg = d3.select("body").append("svg").attr("width",width).attr("height",height);

var chLeft = viz.ch()
      .data(data)
      .fill(function(d){ return colors[d];});

var chRight = viz.ch()
      .data(data)
      .fill(function(d){ return colors[d];})
      .startAngle(Math.PI);

//create g elements and create the chord diagrams in it
svg.append("g").attr("transform", "translate(300,350)").call(chLeft);
svg.append("g").attr("transform", "translate(750,350)").call(chRight);

// adjust the bl.ocks frame dimension.
d3.select(self.frameElement).style("height", height+"px").style("width", width+"px");
</script>

Modified http://vizjs.org/viz.v1.1.0.min.js to a secure url

https://d3js.org/d3.v4.min.js

https://vizjs.org/viz.v1.1.0.min.js