The procedure is an adaptation of the "mode addition" algorithm of Dreift and Trubowitz, in which functions v_N(z) are constructed from a set of k values along the imaginary axis; that is

These values of k have a profound influence on the shape of v(z).

We now define N quantities

where r is an arbitrary positive definite quantity.

The functions g_m and its derivatives with respect to z are used to form the Wronskian determinant.