Additive
Subtype of MethodThe r numbers a₁ , a₂ , ... , aᵣ specified through the key Amount represent the absolute increments between successive elements of the sequence x₁ , x₂ , ... , xᵤ, where:
x₁ is the given externally provided seed number
and
x₁ , x₂ , ... , xᵤ is the requested sequence of u numbers
Formally:
x₂ = x₁ + a₁
x₃ = x₂ + a₂
...
xᵤ = xᵤ₋₁ + aᵤ₋₁
If u - 1 > r, the above formulas still hold under the usual flat extension assumption whereby the extra elements aᵣ₊₁ , aᵣ₊₂ , ... , aᵤ₋₁ are introduced and set all equal to the last number aᵣ
In the common case of r = 1, i.e. when only one number a is defined through the key Amount, the above relations simplify to:
x₂ = x₁ + a
x₃ = x₂ + a
...
xᵤ = xᵤ₋₁ + a
It is obvious that if a = 0, this amounts to the same effect as the choice No Change