Illustration of positional uncertainty. Figure 1 illustrates how positional uncertainty is represented by the proposed oligo functions. In the example, we have an occurrence of a certain oligomer at position -5 (green curve) and -9 (blue curve). The degree of uncertainty depends on the variance σ2 of the Gaussian bumps centered on these positions. Adding the two Gaussians, the smoothness of the resulting oligo function (red curve) increases with increasing σ and the assignment of the oligomer to certain positions becomes more fuzzy.