Function subtract

subtract<T>(a, b, dst?): T
Subtracts two quaternions.
Type Parameters
- T extends BaseArgType = number[]
Parameters
- a: BaseArgType
  Operand quaternion.
- b: BaseArgType
  Operand quaternion.
- Optional dst: T
  quaternion to hold result. If not passed in a new one is created.
Returns T
A quaternion that is the difference of a and b.