pie.padAngle()

pie.padAngle([angle])

If angle is specified, sets the pad angle to the specified function or number and returns this pie generator. If angle is not specified, returns the current pad angle accessor, which defaults to:

function padAngle() {
  return 0;
}

The pad angle here means the angular separation between each adjacent arc. The total amount of padding reserved is the specified angle times the number of elements in the input data array, and at most |endAngle - startAngle|; the remaining space is then divided proportionally by value such that the relative area of each arc is preserved. See the pie padding animation for illustration. The pad angle accessor is invoked once, being passed the same arguments and this context as the pie generator. The units of angle are arbitrary, but if you plan to use the pie generator in conjunction with an arc generator, you should specify an angle in radians.