§21 in The Calculus of Observations: A Treatise on Numerical Mathematics, 4th … For a set of discrete values linear interpolation can approximate other values inbetween, assuming a linear developement between these discrete values. 0 ⋮ Vote. GAUSS FORWARD INTERPOLATION FORMULA y 0 ' 2 y - 1 ' 4 y - 2 ' 6 y - 3 ' y 0 ' 3 y - 1 ' 5 y - 2 • The value p is measured forwardly from the origin and 0