Analysis of three-dimensional grids: four- and five-point cubes

The estimation of quadratic coefficients on four or five data in prismatic array has been regarded as impossible. Estimates of these coefficients can be obtained by means of operational equations that use exponential representation. The coefficients are compared to the true values as obtained by Taylor expansions of the generating functions. If the data are monotonic, the accuracy of the estimations may be sufficient to interest experimentalists.