Function bitternessGravity

bitternessGravity(
    basis: "pre-boil" | "post-boil" | "average-boil",
    preBoilGravity: number,
    postBoilGravity: number,
): number
Which gravity the bitterness model should use, per CalculationOptions.bitternessGravityBasis.

Tinseth recommends the average gravity over the boil. Most calculators use the post-boil figure, and we default to that so our numbers line up with BeerSmith and Brewfather.
Parameters
- basis: "pre-boil" | "post-boil" | "average-boil"
- preBoilGravity: number
- postBoilGravity: number
Returns number
- Defined in ibu.ts:712