How does one use Resources.getFraction()?

You specify fractions in XML as so:

   <item name="fraction" type="fraction">5%</item>
   <item name="parent_fraction" type="fraction">2%p</item>

Where 5% would be 0.05 when actually used.

Then:

// 0.05f
getResources().getFraction(R.fraction.fraction, 1, 1);
// 0.02f
getResources().getFraction(R.fraction.parent_fraction, 1, 1);
// 0.10f
getResources().getFraction(R.fraction.fraction, 2, 1);
// 0.10f
getResources().getFraction(R.fraction.fraction, 2, 2);
// 0.04f
getResources().getFraction(R.fraction.parent_fraction, 1, 2);
// 0.04f
getResources().getFraction(R.fraction.parent_fraction, 2, 2);

As you can see, depending on the type of fraction, the getFraction method multiples the values accordingly.
If you specify a parent fraction (%p), it uses the second argument (pbase), ignoring the first.
On the other hand, specifying a normal fraction, only the base argument is used, multiplying the fraction by this.