In this preliminary study, we provide two methods for estimating the
gradients of functions of real value. Both methods are built on derivative
estimations that are calculated using the standard method or the Squire-Trapp
method for any given direction. Gradients are computed as the average of
derivatives in uniformly sampled directions. The first method uses a uniformly
distributed set of axes that consists of orthogonal unit vectors that span the
space. The second method only uses a uniformly distributed set of unit vectors.
Both methods essentially minimize the error through an average of estimations
to cancel error terms. Both methods are essentially a conceptual generalization
of the method used to estimate normal fractal surfaces.Comment: 10 page