Grouped pie chart segments in d3js using .padAngle() - d3.js

Question

How would I add padding between some groups of segments in a donut/pie chart using d3?
UPDATE
I am using the d3.svg.arc shape generator and .padAngle(paddingFunction) where paddingFunction is defined as:
var paddingFunction = function(d,i) { return i%1==0 ? 0.1 : 0 };
This image is using the paddingFunction described above.
But if I change the padding function to this:
var paddingFunction = function(d,i) { return i%5==0 ? 0.1 : 0 };
I get this image:
Shouldn't the code return two groups of segments with a gap in-between?
Complete code:
// magic numbers
var t = 2 * Math.PI;
var arcHeight = 100;
var innerRadius = 50;
var hours = 10;
function postion(i,offset) {
offset = offset || 0;
return i*(t / hours) + offset*(t / hours)
}
var paddingFunction = function(d,i) { return i%1==0 ? 0.1 : 0 };
// arc generators
var arc = d3.svg.arc()
.innerRadius(function(d,i) { return innerRadius; })
.outerRadius(function(d,i) { return innerRadius + arcHeight; })
.startAngle(function(d, i){ return postion(d.hour);})
.endAngle(function(d, i){ return postion(d.hour,1);})
.padAngle(paddingFunction);
// data
var data = d3.range(0,hours);
data = data.map(function(d) {
return {
hour: d,
color: Math.random(),
}
});
// Scales
var colorScale = d3.scale.linear()
.domain([0, 1])
.interpolate(d3.interpolateRgb)
.range(["#ffffff", "#ffba19"]);
// render viz
var svg = d3.select("svg")
.append("g")
.attr("transform", "translate(320, 320)");
var select = svg.selectAll(".fore").data(data).enter();
select.append("path")
.classed("fore", true)
.style({
"stroke": "black",
"stroke-width": 1,
"fill": function(d) { return colorScale(d.color); }
})
.attr("d", arc);
UPDATE 2
Seems that I misunderstood how the .padAngle() method works. It adds padding on BOTH sides of a segment, I thought it added a gap between segments.
Is there an alternative method in d3 which adds a gap between segements (whilst recalculating the area of the segments so they all keep their proportions)?
Running code: http://blockbuilder.org/GitNoise/13f38aa8f4f2f06dd869